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Big Problem....please Help.

tjcbenz

By tjcbenz
in Ask A GM Technician

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tjcbenz Enthusiast

tjcbenz

Posted
Posted

After finding a leaking w/p gasket last week, today I replaced them. Now after my truck is all done, it's missing, the check engine light flashes and the exhaust smells like rotten eggs. The ONLY things electrical that I unhooked was the battery and MAF. I took the MAF off with the intake tube (GMPP CAI) and set it aside at least 10 feet from where I was working undisturbed. I hooked/and unhooked it with the battery disconnected. When I was initially done with the w/p, I started the truck up, let it run, so I could check it, everything seems fine, nothing overheating, no leaks. At this point in time, I believe the truck was running just fine. Of course I wasn't looking for anything other than leaks, but I sure didn't notice a rotten egg smell or the "missing" sound in my exhaust and so on. Then I shut the truck off to do a few other small unrelated things (i.e. steering shaft), and then I buttoned it up. Then I back the truck out of the garage so I can clean up. I let it idle again in the driveway while I am cleaning so I can again double check for leaks, etc and then take it out for a little spin. Well when I go out to drive it I notice the "missing" sound, I take it a couple hundred yards and turned right around after the check engine light started flashing and of course it wouldn't run worth a shit. I checked and double checked everything incl. the MAF. I just got back from Auto Zone with a rented scanner, when I initially scanned it, it said cyl 8 misfire. I erased the code, started it again, drove it a few feet, this time it says random cyl misfire. If it was the MAF, would it set a code actually for the MAF or would it set another code like the ones I got? How would a MAF only affect 1 cyl?? Again, coolant wise everything seems fine, no leaks, no overheating. So of course I am not happy right now. Any ideas?? Thanks for any help.

Zembonez Senior Enthusiast

Zembonez

Posted
Posted

Rotten egg smell is sulfur from unburnt fuel. Something is dumping fuel into the cats. Flashing CEL means "do not drive" or you are in real danger of ruining the cats. I'm gonna go out on a limb and say you have something not reconnected or not connected properly. There just isn't any other explanation.

tjcbenz Enthusiast

tjcbenz

Posted
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Thanks for the responses. As far as something not connected.....the only thing I touched was the MAF. No more no less. The w/p is hangin right there in the open, except for a belt, nothing in the way. I don't know what I could have done.....

I really wish it is something stupid and it dawns on me all of a sudden so I can get on with things.....I really don't want to tow this f*&!#er to a shop or dealer. Electrical is not my forte.

 

Well if I am burning way rich, wouldn't have to be either a MAF or an O2? I'd think if I forgot the plug something in, I would have a code for it. If it was an O2 I'd think I'd have a code for that also. I guess at this point I am thinking MAF, maybe it behaves like a crank sensor (on Mercedes at least) where it doesn't actually throw a code for it, but throws codes for other things....throws a code for the effect, not the cause. But I am purely guessing here.... anyone? :thumbs::nonod::lol:

pennzoil29 Senior Enthusiast

pennzoil29

Posted
Posted

You didn't reconnect the MAF up backward's, did you? Are all clamp's tight, the electrical plug secure. I hope you can figure it out. Nothing worse than a simple project gone haywire.

tjcbenz Enthusiast

tjcbenz

Posted
  • Author
Posted
You didn't reconnect the MAF up backward's, did you? Are all clamp's tight, the electrical plug secure. I hope you can figure it out. Nothing worse than a simple project gone haywire.

 

I never took it off the intake tube and the connector only goes on one way.....

 

I did a little more looking this morning....and there is literally nothing electrical that is anywhere near what I was working on....only the aforementioned MAF. But I would think I would get a MAF code in this case...... argh I checked all the fuses, thinking maybe something spiked with the battery being disconnected/connected....they all look good....

 

I couldn't agree more with your last statement.

tjcbenz Enthusiast

tjcbenz

Posted
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Well I am going to stick a MAF in it. It's the only thing I touched that has anything to do with fuel metering. I ordered it and they will have it later today. I really hope that's it. That way I can be done with this. Thanks guys for the responses and suggestions and you'll hear from me later for better or for worse :thumbs:

tjcbenz Enthusiast

tjcbenz

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So I go get the MAF yesterday and right before I go to put it in, a buddy calls me back that I had left a message with before. He's been a tech for quite some time. I told him the whole story and he said to unplug the MAF and see if it runs better, if it does, there's my problem. I unplugged it, and...it ran better. Good, found the problem...right? Well I then plug it back in and erase my codes.....been running fine ever since. I never even touched the new one, hopefully they will take it back. So I have no viable explanation. I unplugged the battery a couple times when this first started happening on Sat. for the system to reset itself and to give it a chance to relearn which did not do anything. But unplugging the MAF and plugging it back in seemed to do the trick. It was a huge headache, but at least the damn thing runs again :lol:

longhorn_giant Enthusiast

longhorn_giant

Posted
Posted

I don't know what I hate more, an annoying problem that ends up being something simple to fix but drives you crazy, or a problem that goes away by itself. Both cause a lot of frustration, and usually end up costing you more money for things you don't need. If all you ended up buying was a replacement MAF, I'd say you did really well for yourself even if you didn't have to use it.

 

Glad it's running normal again.

tjcbenz Enthusiast

tjcbenz

Posted
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I don't know what I hate more, an annoying problem that ends up being something simple to fix but drives you crazy, or a problem that goes away by itself. Both cause a lot of frustration, and usually end up costing you more money for things you don't need. If all you ended up buying was a replacement MAF, I'd say you did really well for yourself even if you didn't have to use it.

 

Glad it's running normal again.

 

 

Well they took back the MAF (never installed), so no money out of pocket...just a lot of time, headaches and colorful language :lol:

pennzoil29 Senior Enthusiast

pennzoil29

Posted
Posted
I don't know what I hate more, an annoying problem that ends up being something simple to fix but drives you crazy, or a problem that goes away by itself. Both cause a lot of frustration, and usually end up costing you more money for things you don't need. If all you ended up buying was a replacement MAF, I'd say you did really well for yourself even if you didn't have to use it.

 

Glad it's running normal again.

 

 

Well they took back the MAF (never installed), so no money out of pocket...just a lot of time, headaches and colorful language :dunno:

 

 

:lol: Now that's some good new's.

tjcbenz Enthusiast

tjcbenz

Posted
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My ol' 94 full iron 350 TBI never had any problems!!! It wasn't fast, it didn't get shit for mileage....but you couldn't break it!! :dunno:

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