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Discussion Starter · #401 ·
Today I cleaned the IAC and made a gasket. I took a meter to it, it read between 130-150ish ohms between 2 pair of pins. Going to the other pins resistance was way up in the Megohms. I powered it up while it was out, and like one of the videos warned me, it unscrewed itself completely. I cleaned it up while it was apart, screwed it back in as much as I could, made a gasket from a piece of single layer cardboard (9/16 socket was jut the right size for a template), and put it back together. It took a minute or two to settle down, but it idles more smoothly than previously. I haven't driven it anywhere yet, the 35 is still there. I'll take it out some tomorrow to see if it goes away.


Ironically, the video is 35 seconds. I SWEAR I didn't plan that (but I would have done it if I had!)
 

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When replacing or cleaning the old TBI IAC,is best to unhook battery,wait 30 minutes(LOL we mechanics never did that,just touch neg to pos cables together,wipes basic settings,make sure positive cable is the one yopu unhooked),,then,KO(turn key on),wait 15 to 30 seconds,then KOff,wait 30---do 3 times,and usually can drive it right away with no problems,and no codes,if everything else is OK.
 

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Discussion Starter · #403 ·
It's dark out now and my shoes are off for the night, I'll give it a shot tomorrow while I'm out there working in the driveway. Thanks!
 

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That is AWESOME BK! You might want to clear that code yourself though, it may take quite a while to self-clear.
 

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Discussion Starter · #410 ·
I soldered and shrink tubed the new pigtail in. I had to use the old weather seal, I could NOT get it clipped with the new one in. It looked to be in one piece and still flexible, so I went with it. I then cleared the codes per Mech Bob's procedure and let it run for about 10 minutes, I didn't time it. It was a bit rough at first, but it smoothed out. I didn't road test it, but the SES light didn't come on while it was idling. Pics and video if/when I get some time.

I found the clip on Amazon, with prime it came out within $1 of ordering it from the supplier directly with shipping. Still MUCH cheaper than my FLAPS lists it. If anyone else is looking for one:

http://www.clipsandfasteners.com/GM-Idl ... m?CartID=1

I saw they also have the fuel injector plugs as well. Had I known this last year I might have just bought 2 new ones rather than scouring PnP looking for a good rubber insert.

Fingers crossed this was it...
 

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Discussion Starter · #412 ·
No dice. I checked codes before I left the house, 12 and 83. I drove a mile or so, got a haircut, 3 miles later the light came on. I just checked, 35 and 83. I'm wondering if maybe the throttle body gasket is leaking and is trying to compensate? I sprayed it with carb cleaner while it was idling and heard no difference, but I could have missed it. I didn't spray from the front.

Battery is weak and I need to get some laps in, maybe bbl.

edit:
I took the interstate home, the light stayed off until I was in the driveway reaching for the keys to shut it down.
(and fixed a few big finger/little phone quirks)
 

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Discussion Starter · #414 ·
Whatever grounds were there were reinstalled, I only remember the one on the back of the head and the one by the thermostat. I've even added another one up front a while back. I'll check my diagrams to see if they're shown. I'll get this one way or another.
 

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Discussion Starter · #415 ·
Quick update while getting ready to go out to dinner:

I think I might have found my 35 issue.

I got the cable, got it paired with my old phone (no luck yet on the newer one), and played with the knobs and dials. I reset the code, it came back, I googled and found 35 is thrown when the idle speed is higher than expected. The IAC expected readings matched what is called for, so I looked at the throttle linkage and noticed the cruise control cable was taut at rest. Since the bracket is wrong anyway (but it still worked) I disconnected that cable and reset the code again. This time it didn't come back. I'll l play with it more in 2 weeks (I know!) when I get time, but I have a good feeling about this.

This app/cable is pretty cool. I wish I'd had it 10 years ago when I first got the van.
 

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Discussion Starter · #417 ·
I've not driven the van much since my last post, but so far the 35 has not returned and the SES light has remained off. I played with the ALDL cable/app a little bit tonight, I realized I have a LOT to learn. Part of me wonders how much effort I should invest in learning a system that's 23 years obsolete, the rest of me needs to understand how one of my toys works and what all the lights and readings mean.
 

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Big_kid said:
so far the 35 has not returned and the SES light has remained off.
That is freaking AWESOME! Fingers crossed!
 

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Glad to hear that. I think you've been fighting that ever since the swap.

As for trying to learn more about the obsolete system, that's a tough call. I've got 2 of them here, and haven't really had any issues that have caused me to do any learning of the system. About all I do is read the codes, and try and find the problem. I'll do any component testing before replacing any parts though. My wife's old air cooled 70 VW uses FI, and on it, you use a VOM and a fuel pressure gauge to do any FI work. It doesn't even have a test port or have any codes for diagnostics. The newest version of it is a 73, so it's really obsolete.
 
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