Service Engine Soon

[grond]

So...I was driving home Saturday, towing my boat which weighs no more than 1500lbs. I had been driving about 4 hours (I had the van in tow/haul) when I went to pass a slower car. The tranny downshifted and the "service engine soon" light came on and was flashing. It flashed about 5 times, then turned off...and hasn't been on since. Any ideas?

[chevymaher]

So...I was driving home Saturday, towing my boat which weighs no more than 1500lbs. I had been driving about 4 hours (I had the van in tow/haul) when I went to pass a slower car. The tranny downshifted and the "service engine soon" light came on and was flashing. It flashed about 5 times, then turned off...and hasn't been on since. Any ideas?

Scanner and see what code it was talking about.

[smokinjoe]

Seems odd but that service engine light is not exactly an alarm or anything.

I blocked my egr (on purpose) and it goes on intermittently and has for a few thousand miles/ couple years. Van runs great and I take a thousand mile trip once a month with no issues.

[Leeann_93]

Flashing usually means active misfire.

Could mean plugs, wires, cap, rotor, coil....could mean the fuel injector has an issue.

Get the codes and go from there.

[Isaac Zackary]

My MIL (malfunction indicator lamp or "service engine soon") is also flashing during heavy acceleration at high speeds in second gear. The DTC (diagnostic trouble code) is P0300, multiple misfires. The MIL also does not stay on (weird).

Before this I had just been tinkering around with the distributor trying to eliminate the DTC P1345. The distributor's shaft seems kind of loose and there was quite a bit of metal stuck to the camshaft position sensor. Other than that plugs and wires are all fairly new.

Another thing I've noticed is that while driving it yesterday all day the problem seems to have gotten better. In other words the first time the thing flashed it was on flat road and not under acceleration just a few miles from when I messed with the distributor. I pulled over and restarted the vehicle. Then I went along and it flashed a couple of times going over some passes in Colorado, so I babied it up the mountains. Then it only did it once so far in New Mexico. I'll see what it does today since I have another 6 hours of driving left on my trip to Mexico for today planned out.

My guess is that the distributor it's shot.

[Leeann_93]

Sounds like the distributor gear is shot.

[Astrofarian]

Sounds like the distributor gear is shot.

.....how many miles are on the engine? Stretched timing chain will do that too.

-M!ke-

[Isaac Zackary]

The timing chain is new. The engine has 172k. I've got the Tech 2 hooked up. On the flats only the number 4 cylinder occasionally gets a misfire. It has 1526 total misfires whereas the rest have around 200 on the misfire counter. Accelerating is when get more misfires out of all cylinders. Pulling out of this rest area I'm going to punch it and see what happens. There area also a few holds ahead. I'll do a quick snapshot on the Tech 2 and record the data.

If the distributor gear is shot does that mean I'll have to replace the camshaft too?

Also one of the two distributor cap screws doesn't feel like its tightening up.

[Leeann_93]

If the distributor gear is shot does that mean I'll have to replace the camshaft too?

Also one of the two distributor cap screws doesn't feel like its tightening up.

No. The distributor gear is designed with softer metal to be the sacrificial lamb.

The ears on the OEM distributor are easy to crack if you overtighten them.

[Isaac Zackary]

The MIL no longer flashes at all. Not even during hard acceleration. It hasn't all day anyhow. No MIL, no problem?

So it's magically been curing itself?

I'm at WalMart so I'll check and see if the DTC passes completely the next drive.

How can I tell if the distributor gear is worn?

[Isaac Zackary]

P0300 didn't fail for a whole 20 minute drive.

Could it be that I got some water in the distributor cap and as it dried it ran better and better to where it's now cured?

[Isaac Zackary]

So I erased the DTC P0300 and drove around all day yesterday. The code did not show back up! I'm thinking it had something to do with me not drying the distributor cap as well as I thought I had when I rinsed the dust out of it. Like I said, the MIL would flash at first even just driving down the highway. According to the Tech 2 the captured data showed it happening first at a steady 45mph. But as time passes it got harder and harder to get the MIL to flash. Not that I was trying to get it to flash, at first. But now I can't get the code to pop up at all. I guess I'm calling it good until the MIL turns on again.

[Isaac Zackary]

MIL turned on again on the way back from Mexico. I have two freeze frames stored, both for P0300. One is catalyst damaging misfire (flashing MIL) and the other is emissions misfire (MIL requested).

Number 4 cylinder has the most misfires, about 15,000. Numbers 1, 2 and 3 are around 3,000. But numbers 5 and 6 are only in the lower hundreds.

I think I'll change the distributor anyway but do want to do some testing to make sure it's not something else. Like I said, it has new plugs and wires and the distributor seems to be having other problems.

I have a question. What brand of distributor is best/recommended?: OEM/GM, Spectra, Cardone, Techsmart, other?

[juststartin]

Lots here say skip white distributor. Price is right too

[Isaac Zackary]

Lots here say skip white distributor. Price is right too

Wow! Thanks! $42.50 is a lot cheaper than $100-$150 (or more) for a remanufactured one! I didn't know these existed!

[Isaac Zackary]

Darn it! I got my second Skip White distributor in (the first one had a cracked cap so I sent it back) and I'm still getting a flashing Service Engine Soon light or MIL. So far I have:

New sparkplugs
New sparkplug wires
New distributor
New timing chain

Now What!?

[Leeann_93]

It might be time to look at the spider injector.

But first, remind me: have you done a compression test on the motor?

[Sailing_Faith]

I wonder if you might be getting a leak from the coil? I recently had a misfire caused by my coil, and there was not a visible spark to be seen.....

[Isaac Zackary]

So the first thing to do with P0300, according to the Service Manual, is to "search for applicable service bulletins." Well there seem to be quite a few places on the web that can help me search for such service bulletins. So far I've got:

2001 Chevrolet Astro Engine And Engine Cooling Service Bulletin 147724
Action Number: 10004377
Service Bulletin Number: 147724
Report Date: Feb 01, 2005
Component: Engine And Engine Cooling
Summary: Poor engine performance - misfire, rough idle, service engine soon/check engine light illuminated, diagnostic trouble code (dtc) p0300 set. *tt

2001 Chevrolet Astro Engine And Engine Cooling Service Bulletin 175398
Action Number: 10010375
Service Bulletin Number: 175398
Report Date:
Component: Engine And Engine Cooling
Summary: Service engine soon light and p0300 when towing, cruising uphill or on hard acceleration. *tt

SB #175398 seems to be exactly what's happening in my case. I can drive around town or on flat ground and don't get neither the MIL nor P0300, the Mil will even turn off after a while if it's on solid. But any hard acceleration or hill climbing and the MIL starts flashing and sometimes stays on.

One problem is that I cant seem to find what Service Bulletin #175398 really is about. All I get are summaries. Any idea where I can read the whole service bulletin?

On another note the Service Manual says that P0300 misfiring won't be tested on IF P1345, cam/crank position variance, is detected first. I had P1345 on for a while. When I "fixed" it by filing out the distributor hold down clamp hold and twisting the distributor enough to get rid of P1345 then P0300 instantly became a problem. So either I had P0300 misfiring problems the whole time or there's some connection between my "fix" and P0300.

[Isaac Zackary]

It might be time to look at the spider injector.

But first, remind me: have you done a compression test on the motor?

Nope. I haven't ever done a compression test. I guess I better try that first too. Spider injector. Ya, it would make sense I guess if that's not right. But then is it injecting too much or too little, and during acceleration only? If that's going lean that could make some major engine damage. I do have a new fuel filter, or so the last mechanic said he put a new one in. I don't really trust mechanics anymore.

I wonder if you might be getting a leak from the coil? I recently had a misfire caused by my coil, and there was not a visible spark to be seen.....

Could be. In the manual later on it says to spray the coil with water and see if it increases the misfire count. I'll find out.