92 BlazerPoor Performance Update

Previous post:
Hello,
My father has a 92 Blazer 4DR 4WD V6 (Not A Vortec)190,000 Miles..
he takes very good care of his truck, but lately it's been running like shit. I took it for a test drive and you can't get any power out of it. It seems when you press on the accelerator the engine back fires this will happen until you let of the accelerator. My father plans to do a basic tune-up. Plugs and wires. He changed the fuel pump, fuel filter, oil and trans fluid about 2 months ago, but I believe the last time the plugs and wires were changed was about 1 year ago. I also believe the truck is minus a tail pipe as the weld broke lose and he is currently in a battle with the shop that installed the new exhaust 6 months ago. I would really appreciate any ideas on what could be causing this?


Thanks, Rick


Update:
Hello,
My father and I did almost everything in your tune-up thread BlazerLT and the truck has gotten worse. When you try to accelerate the engine just bogs down and the truck barley moves. I ran diagnostics on the truck and found code 45 o2 sensor so replaced it with no change at all. I reset the computer ran diagnostics on the truck again with OK status. Just to clarify we replaced plugs and wires even though it didn't need it, fuel filter, inspected EGR valve found to be in good condition, flushed radiator (found rusty liquid) ran fuel injection cleaner. The truck is un drivable at this time.

Thank You!

:banghead:

Just curious, have you ran a fuel pressure test on this truck? Could be a problem for you, even with a new pump. if you have a Vortec, 92-95 , a fuel pressure test is critical to starting to look for trouble. Suggest you get a reading when first energized (key on), and when it kicks off (after 2 seconds the fuel pump relay kicks off). watch what it does for a few minutes after this. then take readings while running. First while idleing, and then gunt he motor and see what the pressure does when the throttle is opened. Suggest you start there and reply back so folks here can advise further. May be a bad regulator. Also, check your oil for gas smell, and was the truck getting poor gas mileage?

Rick,

Do you have the Vin W engine with the CPI plate on the top of the engine?

Have you removed and cleaned the EGR valve and reinstalled with a new EGR gasket?

I'm sorry I have a Vortec in my 96 and it's a habit typing the votec. My dad's 92 is not a vortec engine.

We took it to a mechanic and he ran several test on the fuel system and he said all checks out ok! I forgot to mention the fuel pressure regulator was replaced as well.

I'm sorry I have a Vortec in my 96 and it's a habit typing the votec. My dad's 92 is not a vortec engine.

We took it to a mechanic and he ran several test on the fuel system and he aid all checks out ok! I forgot to mention the fuel pressure regulator was replaced as well.

Has the timing been checked? What about the spray pattern on the injectors?

Yes, EGR gasket was replaced after removal.
Yes, timing was checked with no problems found.
No, spray pattern of injectors weren't checked

Yes, EGR gasket was replaced after removal.
Yes, timing was checked with no problems found.
No, spray pattern of injectors weren't checked


I would check that out (injector spray), for giggles I would also check for a clogged cat.

You didn't happen to install the wires in the wrong order did you? Lots of people mix up cylinders 1 and 3 on the cap.

Chance that they messed up the sequence when putting on the new regulator too.

Ok, I brought it in again $$$ had the injectors checked mechanic said he couldn't find anything wrong with the fuel system. I replaced the cat about 3 months so I know that's not it. As for the wires when I first replaced them the car ran great so if I mixed the order up it wouldn't wait 2 1/2 to cause a problem.

Thanks, Rick

P.S I tried to drive the car home from the shop to try and save money on the tow, but I got about a block before it died and wouldn't start for a half hour in which it started again an got me 1/2 block and died and hasn't started sense.

Ok Just picked the truck up from the shop had the injectors inspected and of course the man said there is nothing wrong with them. I got alittle pissed because of all the money I spent for him to give me answers and he keeps sayin nothing is wrong so it didn't cost me dime this time, but the truck is still dead.

Help!

When it does this stuff(stalling for a while) you should check for(strong) spark. My 93 started stalling at random times and would not start for 1-2 hrs last winter. I thought it was a fuel problem but the ignition module was failing. It is very small and sits inside your distributor. If fuel pressure and injectors are OK, would check these out. The module can be removed and tested at most auto parts stores.

When it does this stuff(stalling for a while) you should check for(strong) spark. My 93 started stalling at random times and would not start for 1-2 hrs last winter. I thought it was a fuel problem but the ignition module was failing. It is very small and sits inside your distributor. If fuel pressure and injectors are OK, would check these out. The module can be removed and tested at most auto parts stores.

Right on jsgold with the ignition module. Very easy to remove and test at AutoZone. Pop your distributor cap and remove the two screws and CAREFULLY unplug the wire connectors. The plastic connectors can get brittle and break. Make a good mental note on exactly how they came off so you can re-install later. The connectors are usually fool proofed but if the little tabs break off, you'll be glad you took the time to notice where the wires went. Take the module to your local Auto parts store to test. Mine cost abbout $35.00 USD to replace and got a life time warranty too, which I cashed in 3 years later.

Unfortunatly testing it cold tends not to mean much... I've seen way to many be fine when cold, but once heated up they become flakey...:-/ Not saying you guys are wrong, just I tend not to have a lot of faith in testing ignition modules outside of the attempt to replace them...That's just me though and I'm insane..:)

I'll look into to that next.. Thanks Guys I'll let you know what happens..