94 S-10 Blazer "W" Code eng OBD1 4.3L V-6 ECM location

[Poncho Driver]

Sparky, or anyone else for that matter, who has had experience with Vortec CPI's that were built on a Monday or Friday Please HELP!!!

I am "Poncho Driver" because of a 66 "Goat" I built many years ago. I've always had "Braggin Rights" cars but the only thing to come close to the Poncho is my '89' Regal GSx with the F-3 suspension and big engine mods with ground effects kit I have outrun several Roush Mustangs with it on US 23 at 4:AM the Roush said I walked away from him like he was standing still and he was doing 169. the last time it was smooth enough to look at speedo it was showing 193. then it started dancing with me. thats my pedigree. here is my question

My hunting truck and wifes daily driver is a ninety four 4.3 Vortec 4 door Blazer tahoe "W" code CPI that was clobbered on right front side. Repair folks said it didn't get computer. Thing is it has been a "PIA" ever since. It started burning up O2 sensors, as a result it went in to Dealership(big Mistake) as well as 195 deg. thermostat, for fix. when it came back it ran fine for a week then started stumbling, backfiring and falling on its face. The first thing I found were loose battery terminals. That solved the problem for about a month.

Same thing started up again several weeks. No loose Battery Terminals So I put a code scanner to it and got about 12 codes for vacuum and pressure problems. I pulled the CPI Plenum and all to get at the egr only to find a busted up MAT hose and a broken air intake box and two split vacuum lines Plenum gasket was broken in four place and half the screws were loose. checked the fuel pressure with an actron gauge and it shows 63 PSI when key is turned on and when selonoid cliks it falls back to 59 and holds for at least 2-4 minutes. I figured that was good. Started it up when all was back together and computer ECM fuse as well as battery post (-) had been off for two days to clear codes. the pressure while running was between 55 and 59 (erratic bounce without a control valve on actron pressure gauge to steady the needle) Ran fine for a couple of months and started falling on its nose again. Since then I first went ahead and replaced plugs with AC-Delco, NGK,s were next and finally Bosch Platinum Plus fours before they were burning right, wires, cap and rotor, which seemed to bring it back into line, next rain came and it was doing it again. fixed, and/or replaced hood and firewall gasket attaching it with 3-M yellow super weather strip adhesive dried out distributor and module with commpressed dry air, ran fine. several days later it starts again, no rain but a code for TPS checked and replaced, set IAC Pintle at 1-1/8" instead of 1" and runs fine again. several days later same thing this time code is for MAP sensor, checked it, it was bad, replaced it. ran fine again for several days and then started up again, no codes so I checked the coil, found it to be good checked the Ign. module it was good, checked the two wire coil around the distributor, it was good.

Now its still doing its nasty thing and overheating as well. (I think) because temp gauge on Electonic cluster runs up to 220, 240 then 180; tach goes up and down even while engine is running smooth, engine will register up to 6 MPH while in Park in Driveway when revved and when engine is hesitating and smoking everything on cluster is going haywire. If it's the ECM where in the right front passenger area is it It was built in America, and not Canada I do know that cause the first letter in the VIN is a 1, not a 2. BTW last 25 mile trip Gas consumption was like 12 gallons.

If you have any thoughts on this beside a "FOR STEAL" sign, or as Granny said "Push it over the hill and put a match to it" I'd sure love to hear them.
I hope you won't be offended by e-mail address. I only used the nickname that I carried for twenty years on the fire department "Hebrew" not because of my religion but my luck at being able to walk away from insane situations. MY Chief Petty Officer in the Navy originated it because I was one wayward SOB my fanily is German Irish Catholic and I support the "IRA". so that is why I keep the Name hebrew1966@msn.com

[1993blazerlt]

the PCM is located under the dash on the passangers side

code 12 means nothing, it is normal to get a code 12, were there any codes after that?

have you pulled the EGR to check and see if it is clogged?

[Poncho Driver]

1993blazerlt,

As for codes been there and done that always get a code 12 thats normal it's at the beginning and end of sequences. But I have gotten codes for the EGR, as well as the MAP, TPS, MAT, as well as one or two for O2. Checked all of the above and replaced as necessary

Egr was off when I did the plenum work and I used a dremmel to clean it.

PCM doesn't seem to be there, could it be above glove box or behind the passenger side kick panel?

[T Man]

Wasnt the late 94 and early 95 computer located above the fender well...obd 1.5?

[1993blazerlt]

Wasnt the late 94 and early 95 computer located above the fender well...obd 1.5?

not on the blazers

the pcm is located under the glove box, take off the black plastic shrouds its closer to the kick pannel, when you have the shroud off you will see all the wires going to the computer

[Poncho Driver]

Here's the codes I have gotten, in the case of the ones followed by false these are the ones in which the sensors have so far tested good13, 21, 22, 23-false, 32-false-EGR good, 33, 34, 35-false, 44-false, 45-false, and another 34, which I have not checked yet.

But I feel like the problem is either in the Cluster or the ECM, and since the ECM is easier to remove, I ought to check it first

[Poncho Driver]

I think there may be corrosion or a water leak or a burn't circuit board. On the rare occassion that the wind and rain blow from the Nor-east when the car is parked in driveway headed East, or I hit a waterhole with the passenger side front wheel, or sometimes in a left hand turn, it will act up

[Sparky2263]

Been gone for a few days.

Interpreting all I have read, I gather the current complaint is;

1 Overheating
2 Runs rough. smokes when revved
3 Poor gas mileage
4 No codes stored (even though many have been set previous)


Sure as hell sounds like a clogged converter to me. Unless I'm interpreting badly. If I am, keep it to current issues, I'm getting older and don't take to reading lengthy posts well......

;)

[Poncho Driver]

Been gone for a few days.

Interpreting all I have read, I gather the current complaint is;

1 Overheating
2 Runs rough. smokes when revved
3 Poor gas mileage
4 No codes stored (even though many have been set previous)


Sure as hell sounds like a clogged converter to me. Unless I'm interpreting badly. If I am, keep it to current issues, I'm getting older and don't take to reading lengthy posts well......

;)

Thats what I thought to Sparky but with a wreck that was bad enough to damage the right front fender, door, and hood, I thought a look at the computer for corrosion and a bad E-Prom or mem-cal might be in order before I try to drive it to the shop...or have it hauled(might be cheaper than trying to drive it) but basically they cut a little hole in the converter ahead of the cadium plate and check the flow there against the tailpipe out put I think. One other thying I have noticed is how hot what exhaust is I am getting, so hot at 4" from the pipe it will put blisters on your hand.

Wife said she had a new 195 spec thermostat put in it this past spring, but it just doesn't act like it.

[sammy]

O.k. I may be way off here but if it is the computer getting wet, and you mentioned right front damage, could it be the a.c. drain tube? If it is in that area, it could be cracked, leaking and getting things wet. Then again, you mention the hot exhaust. We used to (back in the day) cut the exhaust after the cat and bore it out. If the vehicle suddenly runs better, we might then replace the cat figuring it was clogged. To do so, you would only need a hack saw, sawsall, pipe cutter or such, and a pipe union to do the job at home. If all goes well, you could then drive it to a local muffler shop to finish.

[Sparky2263]

A piece of 3/4 or 1" steel conduit works great for what sammy speaks of. Thin enough tubing to punch through the converter yet strong enough to take repeated blows from a 32 oz. ball peen.

[Poncho Driver]

Well I guess that is what it is. The computer is dry and the plugs are clean. The converter is discolored ahead, where the exhaust gas comes into it, and normal colored on the backhalf, it's OEM, so without a sawzall I can't get into it. it has some kind of vent holes around it on the outer shield and it looks as if oil or some other matter has boiled out of those holes, according to my son and what I saw in the mirror. So I guess i'll take it to the muffler shop and pony up the $162.50 and let them cut the old one out and sit and watch them do it(LOL)