Relentless PING!

Relentless PING!

Postby Freakist [OP] » December 9th 2010, 5:13pm

Hey! Hi! Howdy!
92 EXT AWD. Motor installed from 94-95 Blazer, 4.3Vin W. Ran like scalded cat till maybe a month and a half ago. In fact, still does, but is slurping down gas worse than a carburated Ford 460, and that's not funny.
Starts quick and idles generally very smooth. Problem appears to hit when it enters closed loop mode after warming up. Absodamnedlutely relentless ping above idle rpm, but only in gear.The freakin thing plain ol SINGS when it is in park or neutral, no ping, very responsive. Gas mileage in the toilet, about 9 MPG or so. Ping not noticeable with foot in it, good acceleration. I'm starting to hear noises I really don't like when I am in gear hitting the gas with the brake on to see if the latest "improvement" has lessened or eliminated the ping, yet those more ominous sounds come and go. I don't want to acknowledge their existence by name unless it's undeniable.
After a year of driving on swapped motor, changed gear ratios to 3.42 from 3.73, to give better mileage on highway.In June 2010, drove vehicle to San Diego from Colorado Springs and back, only minor issues, did however overfill my transmission in the dark parking lot of Walmart in Grand Junction. Drained out some the next morning at a car wash; no apparent damage to trans, it is a 2007 crate 700r4, works real good. Mileage was around 14 on highway as there were a ton of vicious hills on US24 and I was incredibly overloaded, and had not yet changed my DRAC so the speedo read 7 percent SLOWER than actual, as expected, vehicle performed well with original module still being applied to computer. replaced drac & module (and eventually the entire computer) with units from identical drive train (GU6 3.42 ratio) computer, from 92 astro, and that's what it has in it now.
A list of all the things swapped out with working spares (or junkyard replacements) or bought new in an effort to save the favorite of all the vehicles I've ever had:

First, swapped in spare fuel pressure regulator. passenger side did look a little cleaner than it was supposed to be; no help. Tests 64 psi key on, drops to 58 and stays above 50 for at least an hour, tested several times.
Fuel injection system swapped for one from the original motor, 2 years old at swap, no difference in ping or mileage.
Swapped EGR from junkyard, no effect, no codes
SEAFOAMED the motor. No help at all.
swapped both knock sensors from previous engine spare pile. all 4 test at 8.1 ohms, code 42 & 43 go away.
replaced Intake air temp sensor, code 23 went away, probably caused by inadvertent start of engine while sensor unplugged due to installing aftermarket air cleaner.
Replaced Ignition module, cap, rotor and wires, all new, performance, eliminated light show, so far as I have observed. Cleaned platinum plugs, which look very nice, all to no effect whatsoever.
Swapped computer(ECM) from aforementioned 92 astro (a lucky junkyard arrival), this leaves me in EXACTLY the same boat. 3 days later, normal driving, code 43 reappears. problem traced to sensor failure (the small diameter thread version, screwed into the back of the drivers side head), though the ohms still look good. swapped the other one back in.
The thing runs GREAT when you first start it, has small hesitation and progressively louder ping after closed loop (ESC?) starts, depending on engine temperature. ping noise is only evident between approx. 5-10% to maybe 20-25% pedal travel. whatever the actual percentage, it is remarkably constant from one pedal depression to the next. If you romp it the ping duration is very short as engine rpm build and the thing does pretty well on the highway by any standard, except for what is happening to all this fuel? The oil is not wasted, the exhaust is not black, the pump is new and holds pressure, and I don't seem to have any leaks. No O2 sensor codes, no fouling of the plugs,
This is blowing my mind and I will have to sell it and buy a bicycle real soon, I'm not joking.
THINGS I NEED TO KNOW:
can an egr, or even more unbelievably 2 egrs die or leave the valve shut and throw NO CODES?
The ACTUAL MEANING OF THE CODE 43 IS WHAT? Is it that the voltage has been too high or low for 20 seconds, or is it that the ECM has gotten a steady ping signal for 4 seconds or more? When it recently threw code 43 it was noticeably attempting to retard the timing just before throwing the ses light on for a few seconds, as I was easing out of a 7-11 parking lot, part throttle, pinging like mad as has become usual. I get differing info online, need some authoritative input.
If the 2 different fuel injection spiders and regulators were both leaking identically, could the o2 sensor fail to detect that I'm using 50 percent more gas than usual or throw NO CODE AT ALL?? Come on, whats up with having a computer if it can't tell your burning this much extra?
On the other hand, wouldn't my exhaust look black, wouldn't the engine stumble on that volume of fuel? and with that kind of fuel usage, how could this actually be spark knock? I thought it had to be pretty lean for that to happen at all. how could I have replaced so many things and STILL not made a dent?
Could the CAT cause ping? and only at a certain rpm range? The exhaust appears to flow freely, and the midas guy did a great job 2 months ago.
Could the fuel issue and the ping be separate issues? I'm tellin ya EVERYBODY that rode in this van for the last 2.5 years has a comment on how smooth it runs (Even now!), and how strong it accelerates. Not like I'm an overactive leadfoot or anything... really! I do like to go fast yet I take extreme care of my engines.
MIND BLOWN. :banghead:

Lil Help?
PLEASE?
Original Poster [OP]
Freakist
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Re: Relentless PING!

Postby Freakist [OP] » December 9th 2010, 6:41pm

I know that the idea of being a PARTS CHANGER is held in ill repute by some folks, and yet, what tests would a person have done other than swap out the obvious and see how it does? Surely there is an answer to this dilemma, the only thing that really gives me hope about it is that I noticed just this morning that it happens only when the thing goes into closed loop mode. That tells me it is something that the ECM is toying with. But what, since I've replaced just about everything, and of the used parts only one has shown a problem so far. I do these parts replacements in a methodical manner, so I can trace what if any difference in operation occurred due to what action.
I have no idea how one would initially diagnose a problem like this that presents with only a pair of knock sensor codes and an unplugged IAC. I don't have a scanner and that's because I don't know if I can get anything useful from the odb1 aldl for the expenditure. If it was odb2 well that's another thing.
BTW, since I put in an engine with the crankshaft position sensor, on a way out thought, could this van be upgraded to obd2, if I swapped out the whole harness? I dunno how many more sensors the 95 1/2 + astros had beyond what the 92-95 early had. perhaps I could only get to odb1.5, eh? wassaaaap?
Thanks!
Original Poster [OP]
Freakist
Fueling (Empty tank)
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Re: Relentless PING!

Postby Phantom » December 9th 2010, 6:52pm

43- knock sensor circuit
CODE 43

Trouble Code 43 indicates that there may be a malfunction in the Electronic Spark Control (ESC) circuit.

ESC is used to sense spark knock (pinging) and retard the timing to eliminate it. A knock sensor (located at the rear of the engine block) sends signals to an ESC module which then signals the ECM that knocking is being detected. The ECM will retard the timing by as much as 20 degrees in 1 degree increments. A loss of knock sensor signal or loss of ground at the ESC module will cause the signal at the ECM to remain high. The ECM will act as if no knock is present, and may possibly result in engine damage, if there is detonation.

Loss of the ESC signal to the ECM will cause the ECM to constantly retard the timing to its maximum. This results in sluggish performance and a Code 43.

The conditions for setting this code are:

* Engine is running
* ESC input signal has been low more than 2.23 seconds


Typical causes for this code include:

1) Open or shorted knock sensor
2) Loose knock sensor
3) Excessive mechanical noise within engine
4) Improper or incorrectly installed PROM or CALPACK in the ECM or defective ECM
5) Intermittent open in the EST line to the ignition module
Phantom
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Re: Relentless PING!

Postby Phantom » December 9th 2010, 7:02pm

In cases like yours it would be beneficial to have a real time OBD diag scan performed, not just a code reader, it should help pinpoint exactly where the problem is , it is possible that coolant temp sensors signal ECM to enrich fuel for cold temps , changing to OBD 2 is possible , but depending on how much you have to change will determine cost , likely to be cheaper to have a scan done on your van,,If you have a laptop ,all you need to do is buy a cable to interface with your OBD 1 connector and plug into your laptop and download a free prog and run a scan on your van. it may take you a little time to learn how but afterward it will save you a lot of money in future diag scans
Phantom
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Re: Relentless PING!

Postby Freakist [OP] » December 9th 2010, 7:41pm

In reference to Phantom

Ok, I will thank you for your interest firstly and express my desire as a new poster here to not be coming off like a jerk.
However, thats the same info I used to start my examination of the knock sensor circuit, in fact looks eerily similar to the text from my Blazer book, and you know what, THERE IS NO ESC MODULE IN A 92 ASTRO VAN. I tore the harness COMPLETELY APART, and unless there is a MICROSCOPIC UNIT, this information does not apply to the 92 vin W astro van, which is why I replaced the entire ECM, since the dark blue wire goes directly there, no pass go, no 200 dolla. I even collected an esc module from a junkyard (vin z machine), and try as I might in the junkyard or home cannot find a discreet ESC module on a vin w astro to save my genitals.
This information may be of value to someone with vin Z, but I'm not that guy. I was kinda hopin that I could get something more than just cut and paste, since I've already read probably every word concerning relevant search terms throughout the web and nothing has helped.
2 ecms with bad esc circuits are pretty much gonna be a difficult prospect to generate in as random a fashion as this in my estimation, and yet it seems faulty information is in abundance.
So, unless you can go out and take a picture of the ESC module that you plug the sensors into and then plug that little ole module into the ECM, in a 92 Astro van vin W, and post it with an explanation of how to enter the dimensional rift wherein it is contained, I will have to assume that aliens modified my van when I was in the bathroom, or that this information is of little to no value to me solving this problem.
Thanks again.
Original Poster [OP]
Freakist
Fueling (Empty tank)
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Re: Relentless PING!

Postby Freakist [OP] » December 9th 2010, 7:50pm

Phantom wrote:In cases like yours it would be beneficial to have a real time OBD diag scan performed, not just a code reader, it should help pinpoint exactly where the problem is , it is possible that coolant temp sensors signal ECM to enrich fuel for cold temps , changing to OBD 2 is possible , but depending on how much you have to change will determine cost , likely to be cheaper to have a scan done on your van,,If you have a laptop ,all you need to do is buy a cable to interface with your OBD 1 connector and plug into your laptop and download a free prog and run a scan on your van. it may take you a little time to learn how but afterward it will save you a lot of money in future diag scans



I really didn't know an odb1 scan would tell me anything of note. I will investigate their capabilities directly.
When its cold running for the first few minutes it runs wonderfully, and very suddenly switches to ping central.
I still don't get how it could be rich and pinging too.
I'll be gone for a few hours finding that connector you mention and will take my laptop with. perhaps comeback with some answers.
Thanks, Steve.
Original Poster [OP]
Freakist
Fueling (Empty tank)
Fueling (Empty tank)
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Re: Relentless PING!

Postby Freakist [OP] » December 9th 2010, 7:51pm

Phantom wrote:In cases like yours it would be beneficial to have a real time OBD diag scan performed, not just a code reader, it should help pinpoint exactly where the problem is , it is possible that coolant temp sensors signal ECM to enrich fuel for cold temps , changing to OBD 2 is possible , but depending on how much you have to change will determine cost , likely to be cheaper to have a scan done on your van,,If you have a laptop ,all you need to do is buy a cable to interface with your OBD 1 connector and plug into your laptop and download a free prog and run a scan on your van. it may take you a little time to learn how but afterward it will save you a lot of money in future diag scans



I really didn't know an odb1 scan would tell me anything of note. I will investigate their capabilities directly.
When its cold running for the first few minutes it runs wonderfully, and very suddenly switches to ping central.
I still don't get how it could be rich and pinging too.
I'll be gone for a few hours finding that connector you mention and will take my laptop with. perhaps comeback with some answers.
Thanks, Steve.
Original Poster [OP]
Freakist
Fueling (Empty tank)
Fueling (Empty tank)
Years of Membership: Freakist has been a member for 10 full yearsFreakist has been a member for 10 full yearsFreakist has been a member for 10 full yearsFreakist has been a member for 10 full yearsFreakist has been a member for 10 full yearsFreakist has been a member for 10 full yearsFreakist has been a member for 10 full yearsFreakist has been a member for 10 full yearsFreakist has been a member for 10 full yearsFreakist has been a member for 10 full years
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Re: Relentless PING!

Postby Phantom » December 9th 2010, 8:24pm

Freakist wrote:

I really didn't know an odb1 scan would tell me anything of note. I will investigate their capabilities directly.
When its cold running for the first few minutes it runs wonderfully, and very suddenly switches to ping central.
I still don't get how it could be rich and pinging too.
I'll be gone for a few hours finding that connector you mention and will take my laptop with. perhaps comeback with some answers.
Thanks, Steve.

OBD = On Board Diagnostic

It is the connector under the dash on the driver side where a Tech connects a cable to a laptop or plugs in a OBD scanner , same place where a code reader plugs into but a scanner reads the live data that is being produced through the ECM on board computer.
The pinging could be the result of what the on board computer does in trying to compensate for a malfunction it discovers only it is not able to correct the problem , and o2 sensor can cause it , and from what I have read there are 2 knock sensors on that engine . If you use a laptop you will need a special cable that interfaces the laptop with the OBD port on the vehicle and you will need a diag program on the laptop that communicates with the OBD computer on the van,

93-95 4.3L VIN W
Code 43
Knock sensor signal was either above 3.5 volts or below 1.5 volts for at least 20 seconds.

http://www.troublecodes.net/GM/94-95_43W.shtml

http://www.google.com/search?q=Code+43+ ... =firefox-a

Here is a link that has free OBD 1 diag programs and they have a cable , you can make one but their cable is good and works very well .

http://www.aldlcable.com/


5) Intermittent open in the EST line to the ignition module

"When its cold running for the first few minutes it runs wonderfully, and very suddenly switches to ping central.
I still don't get how it could be rich and pinging too."

sudden switch is likely caused by a signal to ECM to change setting due to signal received , this could be a loose or frayed wire connection, a bad ground , faulty sensor . a too far retarded timing can also behave similar to a too far advanced timing,,
Overly Retarded timing will over heat fuel quickly. will allow the fuel/air mixture to continue to burn while the piston travels away from TDC. This causes a lot of heat to be absorbed into the cylinder wall that would not normally be there. The burn occurs over about 80 degrees of crank rotation, when started late, there isn't time for the the flame temps to be reduced by work against the crank. when this occurs the exhaust valve opens and dumps really hot gases into the exhaust passages. This greatly increases the valve temp and the amount of heat picked up into the head and exhaust port. The cooling system has to try to absorb the additional heat and thus the engine block and other surfaces retain more heat than normal and the head combustion chamber may still have "hot spots" that tend to ignite the fuel , this fighting against itself is similar to pre-ignition when the fuel is ignited before TDC and trys to push the piston downward while it is being pushed upward by the crankshaft.
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Re: Relentless PING!

Postby jeff's93astro » December 9th 2010, 10:27pm

in 92 the ESC module is built into the computer. The older TBI motors had the ESC beside the TBI but GM decided to build the ESC into the ECM sometime between 90-92 but i'm not sure exactly when
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Re: Relentless PING!

Postby Phantom » December 10th 2010, 3:49am

After reading some flow charts on this matter I found some info and have a link that shows pics of EEPROM on OBD 1 computer internals , I seen a chart where the ECM for a given year is the same for the 4.3 and the 5.7 , so info on the 5.7 may be somewhat of assistance in knowing how it operates and corresponds with the vehicles.

http://www.lt1swap.com/ecmtuning.htm

Knock Sensor
The knock sensor system is used for the detection of detonation. The computer retards spark advance based on the amount of knock received. The knock sensor produces an ac voltage according to the amount of knock. The computer receives the signal and it's programming determines how the computer will change the spark advance.
Diagnostic Trouble Code 43 (OBD-I) or P0332 (OBD-II) can result from a knock sensor circuit or sensor that is faulty. When the DTC is present, the computer will automatically retard timing to protect the engine (since it can no longer sense potentially destructive detonation). Timing can be retarded 10° or more in some driving situations. Performance will be affected.
The sensor resides on the RH side (passenger) of the engine block, in the coolant drain location. The F-body uses only one sensor. Other body platforms may use two sensors on their LT1 applications.
On the 1994-1997 LT1 F-body PCM, there is a replaceable module that receives the knock signal. 1993 ECM's have the receiver circuitry built-in to the computer and have no replaceable module.
You may have heard about an LT4 knock module. This module came from the 1996 LT4 Corvette, that had roller rockers as standard equipment. The LT4 module is tuned to allow for the noise the rockers make (not perceiving it as knock). If you have similar valvetrain modifications on your LT1, it may be a good idea to swap to the LT4 module to reduce the chance of "false knock" (knock not related to detonation).
The LT4 module can be used on 1994-1997 engines (OBD-I and II) and no change of the knock sensor is needed (even though the sensors changed in 1996). There is no specific LT4 knock sensor. However, there are differences in the impedance of the sensors between OBD-I and II as listed in the testing section below. You must use the sensor that is matched to your OBD type (or have a wiring modification as frequently done in an OBD type swap situation).

Testing
With the connector off the knock sensor, check for 5v on the harness terminal with key ON. Continue if that is good. If not good, check at pin C8 (1993), D22 (94-97) on back of computer. If voltage is ok at the back of the computer, repair the wire from the computer to the sensor.

Key OFF. Connector off at the knock sensor. Measure the resistance between the KS terminal and ground. Resistance should be between 3300-4500 ohms (OBD-I) or 93k-107k ohms (OBD-II). If it is not, the sensor is faulty or the sensor is not making good contact with the block. Try another resistance reading from the sensor terminal to the outside metal of the sensor body.
If all that is good, it might be a faulty knock module (in case of 94-97) or a problem with the computer, itself.
OBD-I (1993-1995) knock sensor GM PART # 10456126 ACDelco #213-96
OBD-II (1996-1997) knock sensor GM PART # 10456287 ACDelco #213-325



The following info is for a 97 4.3L W OBD 2 , ,.... from what I have read there are some similarities with the OBD 1 system ,

1. Turn the ignition OFF.
2. Disconnect the PCM connector at the PCM.
3. With a DVM connected to ground measure the resistance at the Knock Sensor signal circuit cavity.
90 K ohms-110 K ohms
The replacement VCM is supplied without a KS Calibration PROM so for reuse in the new VCM carefully remove the PROM from the defective VCM.
# Remove the Calibration PROM.

* Using the thumb and first finger, remove the KS Calibration PROM by gently squeezing each end of the blue KS Calibration PROM Pull upward.
* Do not remove the cover of the KS Calibration PROM. Use of an unapproved KS Calibration PROM removal methods may cause damage to the KS Calibration PROM or the socket
# Inspect for the alignment notches of the KS Calibration PROM.
# Carefully set it aside.
# Do not open the KS Calibration PROM
# Remove the new VCM from the packaging.
# Check the service number in order to make sure it is the same as the defective VCM. Remove the access cover.

Installation of KS Calibration PROM
Press only on the ends of the KS Calibration PROM. The small notches in the KS Calibration PROM must align with the small notches in the KS Calibration PROM socket. Gently press on the KS Calibration PROM until it is firmly seated in the socket. Listen for the click.
# Install the KS Calibration PROM in the KS Calibration PROM socket.

# Install the access cover on the VCM.
# Install the VCM in the engine compartment.

# Install the connectors to the VCM.
# The MIL, antilock and brake lamps will continue to be enabled until the VCM is programmed. Once the programming is complete, the lamps will turn off and normal operation will occur.
# Connect the negative battery cable.

The ignition should always be OFF when installing or removing the VCM connectors in order to prevent damage

EEPROM Programming

1. Take the following steps in order to set-up for the EEPROM Programming.
* The battery is charged.
* The ignition is ON.
* The battery and cigarette lighter connection is secure.
* The Data Link Connector (DLC).
2. Refer to up-to-date Techline terminal and equipment user's instructions.
3. If the VCM fails to program, do the following functions:
* Check all the VCM connections.
* Check the Techline terminal and equipment for the latest software version.
* Try again to program the VCM. If it fails again, replace the VCM.

# Perform the IAC valve reset procedure with the scan tool. Use misc. test.
# For a functional check perform one of the steps:

* Use the Techline terminal and equipment in order to perform the On-Board Diagnostic (OBD) System Check

Refer to Powertrain On Board Diagnostic (OBD) System Check .

Flow chart indicators that a improperly functioning knock sensor circuit will contribute to poor fuel mileage

The VCM in this vehicle is programmable. The only services allowed on the VCM is the control module replacement with the KS calibrator PROM transferred or the KS calibrator PROM only.

The KS calibrator contains the up integrated knock sensor calibration. The VCM stores the 4 calibrations in the Electronically Erasable Programmable Read Only Memory (EEPROM).

When replacing the VCM, programming the EEPROM and transferring the KS calibrator PROM to the new VCM is mandatory. Refer to the EEPROM Programming .

The 4 calibrations required for the VCM are the Powertrain, the ABS, the VSS buffer, and the A/C. Each calibration has its own part number. Determine the correct calibrations for a particular vehicle based on the VIN number of the vehicle.
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Re: Relentless PING!

Postby Gary » December 11th 2010, 12:01am

Phantom wrote:After reading some flow charts on this matter I found some info and have a link that shows pics of EEPROM on OBD 1 computer internals , I seen a chart where the ECM for a given year is the same for the 4.3 and the 5.7 , so info on the 5.7 may be somewhat of assistance in knowing how it operates and corresponds with the vehicles.

http://www.lt1swap.com/ecmtuning.htm

Knock Sensor
The knock sensor system is used for the detection of detonation. The computer retards spark advance based on the amount of knock received. The knock sensor produces an ac voltage according to the amount of knock. The computer receives the signal and it's programming determines how the computer will change the spark advance.
Diagnostic Trouble Code 43 (OBD-I) or P0332 (OBD-II) can result from a knock sensor circuit or sensor that is faulty. When the DTC is present, the computer will automatically retard timing to protect the engine (since it can no longer sense potentially destructive detonation). Timing can be retarded 10° or more in some driving situations. Performance will be affected.
The sensor resides on the RH side (passenger) of the engine block, in the coolant drain location. The F-body uses only one sensor. Other body platforms may use two sensors on their LT1 applications.
On the 1994-1997 LT1 F-body PCM, there is a replaceable module that receives the knock signal. 1993 ECM's have the receiver circuitry built-in to the computer and have no replaceable module.
You may have heard about an LT4 knock module. This module came from the 1996 LT4 Corvette, that had roller rockers as standard equipment. The LT4 module is tuned to allow for the noise the rockers make (not perceiving it as knock). If you have similar valvetrain modifications on your LT1, it may be a good idea to swap to the LT4 module to reduce the chance of "false knock" (knock not related to detonation).
The LT4 module can be used on 1994-1997 engines (OBD-I and II) and no change of the knock sensor is needed (even though the sensors changed in 1996). There is no specific LT4 knock sensor. However, there are differences in the impedance of the sensors between OBD-I and II as listed in the testing section below. You must use the sensor that is matched to your OBD type (or have a wiring modification as frequently done in an OBD type swap situation).

Testing
With the connector off the knock sensor, check for 5v on the harness terminal with key ON. Continue if that is good. If not good, check at pin C8 (1993), D22 (94-97) on back of computer. If voltage is ok at the back of the computer, repair the wire from the computer to the sensor.

Key OFF. Connector off at the knock sensor. Measure the resistance between the KS terminal and ground. Resistance should be between 3300-4500 ohms (OBD-I) or 93k-107k ohms (OBD-II). If it is not, the sensor is faulty or the sensor is not making good contact with the block. Try another resistance reading from the sensor terminal to the outside metal of the sensor body.
If all that is good, it might be a faulty knock module (in case of 94-97) or a problem with the computer, itself.
OBD-I (1993-1995) knock sensor GM PART # 10456126 ACDelco #213-96
OBD-II (1996-1997) knock sensor GM PART # 10456287 ACDelco #213-325



The following info is for a 97 4.3L W OBD 2 , ,.... from what I have read there are some similarities with the OBD 1 system ,

1. Turn the ignition OFF.
2. Disconnect the PCM connector at the PCM.
3. With a DVM connected to ground measure the resistance at the Knock Sensor signal circuit cavity.
90 K ohms-110 K ohms
The replacement VCM is supplied without a KS Calibration PROM so for reuse in the new VCM carefully remove the PROM from the defective VCM.
# Remove the Calibration PROM.

* Using the thumb and first finger, remove the KS Calibration PROM by gently squeezing each end of the blue KS Calibration PROM Pull upward.
* Do not remove the cover of the KS Calibration PROM. Use of an unapproved KS Calibration PROM removal methods may cause damage to the KS Calibration PROM or the socket
# Inspect for the alignment notches of the KS Calibration PROM.
# Carefully set it aside.
# Do not open the KS Calibration PROM
# Remove the new VCM from the packaging.
# Check the service number in order to make sure it is the same as the defective VCM. Remove the access cover.

Installation of KS Calibration PROM
Press only on the ends of the KS Calibration PROM. The small notches in the KS Calibration PROM must align with the small notches in the KS Calibration PROM socket. Gently press on the KS Calibration PROM until it is firmly seated in the socket. Listen for the click.
# Install the KS Calibration PROM in the KS Calibration PROM socket.

# Install the access cover on the VCM.
# Install the VCM in the engine compartment.

# Install the connectors to the VCM.
# The MIL, antilock and brake lamps will continue to be enabled until the VCM is programmed. Once the programming is complete, the lamps will turn off and normal operation will occur.
# Connect the negative battery cable.

The ignition should always be OFF when installing or removing the VCM connectors in order to prevent damage

EEPROM Programming

1. Take the following steps in order to set-up for the EEPROM Programming.
* The battery is charged.
* The ignition is ON.
* The battery and cigarette lighter connection is secure.
* The Data Link Connector (DLC).
2. Refer to up-to-date Techline terminal and equipment user's instructions.
3. If the VCM fails to program, do the following functions:
* Check all the VCM connections.
* Check the Techline terminal and equipment for the latest software version.
* Try again to program the VCM. If it fails again, replace the VCM.

# Perform the IAC valve reset procedure with the scan tool. Use misc. test.
# For a functional check perform one of the steps:

* Use the Techline terminal and equipment in order to perform the On-Board Diagnostic (OBD) System Check

Refer to Powertrain On Board Diagnostic (OBD) System Check .

Flow chart indicators that a improperly functioning knock sensor circuit will contribute to poor fuel mileage

The VCM in this vehicle is programmable. The only services allowed on the VCM is the control module replacement with the KS calibrator PROM transferred or the KS calibrator PROM only.

The KS calibrator contains the up integrated knock sensor calibration. The VCM stores the 4 calibrations in the Electronically Erasable Programmable Read Only Memory (EEPROM).

When replacing the VCM, programming the EEPROM and transferring the KS calibrator PROM to the new VCM is mandatory. Refer to the EEPROM Programming .

The 4 calibrations required for the VCM are the Powertrain, the ABS, the VSS buffer, and the A/C. Each calibration has its own part number. Determine the correct calibrations for a particular vehicle based on the VIN number of the vehicle.


:clap: :clap: :goodpost: :goodpost: Outstanding!!.
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Re: Relentless PING!

Postby Duster776 » December 11th 2010, 5:03am

In response to the above post, my old 92 GMC P/U, I had to re-run the the wire from the ECM to the knock sensor module...it had gone bad, took quite a bit of time to find this problem. Patience is key, but not always likely!
Dan K
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Re: Relentless PING!

Postby Phantom » December 11th 2010, 10:04am

Duster776 wrote:In response to the above post, my old 92 GMC P/U, I had to re-run the the wire from the ECM to the knock sensor module...it had gone bad, took quite a bit of time to find this problem. Patience is key, but not always likely!

What led you to discover that the wire had gone bad? was there visible damage to the wire and or connections? possibly no continuity? Did you discover something along the way that would help simplify the diagnosis and pinpoint the problem ? Ping can be a serious problem and anything that helps identify the problem source and fix is always helpful.
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