The End Of My Sonoma?

[Blownexploder94]

thats a pretty shotty diagnoses if i ever heard one

[GmcNoma95]

Pull apart the block and rebuild it bigger and better. If the block is reusable which it should be...!

[Gallon of Fuel]

Late to the party but if it smells like gas, it's probably gas related. The injector circuit on the ECM is likely cooked, not uncommon on these but having 2 fail simulatenously is unlikey. There used to be a guy on eBay selling used ECMs that he would program for your VIN, and they were cheap ($80 I recall?). Then it's just do the BCM relearn procedure and start it up. I'd be very surprised if it didn't turn out to be a shorted injector (testable via multimeter), a sticky injector, or the injector circuit on the ECM.

[rockyroad217]

mine did the EXACT same thing and it was an injector..it left me stranded in the next town..dont sell your truck, just test the injectors..start it up and use a stethescope or something and listen for the injector pulsing..compare it with cyl 3 and 4 that are running right and see what you find out

[Nitemare]

test the injectors definitely. also i hope you replaced the 2 plugs that were soaked.

[jpdodge150]

I've got me a lil 1999 s10 and have been doin a lot of research since I've had it and I decided to voice my opinion here since i'm a diesel tech and we work with nothing but electronic injections systems now. I'm also currently in my advance electrical class, so I figured I would try my best to help out while the knowledge is fresh. The thing that really sticks out to me is that you have two cylinders drop at the same time and the plugs are soaked with gas. I don't know about the missing thing your mechanic said because then it would be popping and backfiring blah blah blah (If you have spark). Not saying he's wrong though. My first thought would be to replace the injectors with some known good ones and check the connectors while your at it. I've heard of the terminals inside of them coming loose and causing random missfires or possible even shorting. Which by the way could be relating to what the mechanic said about the missing. Of course if they are shorting, it's possible that it could feed back to the ecu and blow that dudes mind away. I don't know about yall but that's what it really sounds like, either a bad injector, short to ground, or a bad ecu. Maybe even all three. Which could get expensive quick. Another thought, (you may have answered this already) do you have a good strong spark at those two plugs? You mentioned that you replaced those coil's and I wouldn't be surprised if something failed over in that area since its been disturbed. There is just this rule that my instructor always told me, if a part has been replaced, moved, or even touched, it should be the first thing to check. Could very well be a faulty coil shorting or even just a bad connector causing a random miss fire. Your best bet is to take it to an automotive electrical shop since they probably have the proper testing equipment. Ok now I just thought of another thing that bothers me that may be related to a bad injector or a short. You said there was white smoke which could be unburnt fuel going through the hot manifold. If the injector was shorted to a hot common wire or something along that line, they could both stick open and just poor fuel into the cylinder. If they went bad (which is why I say try to find a set of good used ones if you can) they could also be leaking down, but that's a hell of a lot of fuel to be leaking down on just 60psi. We normally deal with up to 30,000psi on certain common rail diesel engines. Of course if the injector shorted it would probably burn up pretty quick. I know this is allot of possible problems but it at least its in the basic area of fuel, air, and ignition. Its all about the process of illumination. Hope this helps out, and good luck!

PS: I really like rockyroad217's idea, this will at least tell you if it is an injector problem, then you can narrow down the problem to either be the injector itself or possibly the electrical system.

[Neuterbigwilly]

wow, great info, i got my truck back from the mechanic. he said to change the logic module, and that would be a 50/50 shot. gave a a read out that ill have to post later for the simple fact that i dont have it on me. but it said somthing like could be vss, ecm, tps, ics, a whole bunch of stuff. and that was just one code. he didnt look into the truck too much because he didnt want to rip me off and not fix the problem. so he told me to replace the logic module with a used one from pick,n,pull. (local used pull your own parts place) swap them out and hope forthe best

[Nitemare]

wtf is a logic module that sounds like a piece of a board game or something

[Neuterbigwilly]

he told me that it was bolted to engine in most cases, and that the coil packs are bolted to that, but dont take my word for it! just telling you what my mech said! is he lying?

[Nitemare]

i searched logic module on ebay, and not a single one was for a car

[Neuterbigwilly]

hhhhhhhhhhhhm, anyone else have an opinion here? is it an actual thing, or is my mechanic a pile of crap? lol

[Nitemare]

sounds to me like the mechanic made it up

[Neuterbigwilly]

anyone else know of this thing? if not then WTF! lol

[jpdodge150]

I think it's just a fancy name for the engine control module or ECM. I've heard that name once before and I'm pretty sure that's what he meant. It doesn't hurt to pick up the phone and call him to clear it up. Better to feel dumb for a few moments than for the rest of your life, plus you might save your wallet in the long run.

[Neuterbigwilly]

ok, where is the exact location of the ecm? i just bought a 98 chevy 2500. nice condition. so im going to drive that, and fix my sonoma over the winter. so where is the ecm? where can i get a new one?

[Nitemare]

ecm should be monted on top of the coolant over flow bottle.

[Blownexploder94]

or he is thinking ICM

[Neuterbigwilly]

ok, ecm i have now. icm? no idea where that is, i would have to assume it is ignition cont mod. am i right? where would it be, and is there a pcm?

[Blownexploder94]

you are correct, and its what the coils are held to

[Blownexploder94]

and the pcm is the ecm, used to be called powertrain control module now its engine control module

[Neuterbigwilly]

awsome. thanks guys. so which one should i replace first?

[Nitemare]

ask the retard mechanic what he was talking about before you go spendin money

[s10dan]

Check you oil and make sure that its not milky looking and that its not overly full. If white smoke was coming from the exhaust smell it and see if it smells like coolant. If that checks out to be ok then I would look to see if maybe your fuel pressure regulator is working. On the fuel line there will be a valve that has a cover on it like the valve on your tire, Check the pressure there. It could be low fuel pressure from fuel pump(not likely) or a bad regulator. Your ECM will in most cases out last your truck but not always. Please dont spend any money till you find the problem, that will only lead to you wanting to kick yourself.

[CouJoe56]

Im not saying im a brilliant guy or anything. but i have never heard of a "logic module"

elaborate please

[Neuterbigwilly]

hahahahahaha ok, so i called my mech. he says that it is under my coil packs. but he is guessing whether or not that is the problem. he swears up and down that hes 99% sure it IS electrical. NOT mechanical! but he made up some weird name for an icm. lol. dont take me wrong, im not a moron. do most of my own work. im pretty handy. just still learning this peticular vehicle. yes, i checked the oil, its fine, i smelled the smoke, just straight gas! choked me. and the pressure was 45 i think. atleast extremely close to that.

[CouJoe56]

so your ignition module? if u live by an advance auto we test those!

at least at mine we do

[Neuterbigwilly]

ok, ill have to call mine and see if they can. good idea