94LT1, air filter oil?

[94conv.]

Can oil from a K&N air filter mess up a MAF to cause intermitent stumbling and stalling after shutting the car off for about an hour after a 120 mile drive? I have an intermitent problem and have no codes. When it runs, it runs great. Let it sit and restart it and it stumbles and falls. And this doesnt happen everytime.

 

[Hib Halverson]

While "over-oiling" an oiled-cotton filter can cause MAF problems, you symptoms sound more like leaking injectors.

Run the fuel pressure tests in the Service Manual. That will tell you if you have an injector problem.

 

[94conv.]

Thank you. I'm just back tracing my steps to when this all started last fall. I had a mechanic look at it back then and said the fuel pressure was good and the injectors ohmed out ok and vaccum was good and ended up replacing the optispark, cap and rotor anyway, not the whole thing. Happened again so I had someone replace the ignition coil and module because they looked pretty bad. It ran great after that for a couple months when I put it up in November but now its back at it since I started driving it again a week ago. One time it may run great, it still idles better then it has in years after the ign changes. You just cant trust it, the next time you shut it off and go to get back in it, it may start stumbling and die and may not even start for awhile. Thought about it being the TPS or EGR but I dont know. I'm looking for a place to take it that I can trust will fix it.

 

[purplec4]

Over oiling k+n filter

MY 95 LT1 did the same thing for about a year. Start it up to go to store and it would run great, come out of store and it would barely idle and was down on power, did this off and on until I found a bad catalytic converter. Converter came apart and the pieces were moveing around inside it which explained why it ran so good sometimes and like crap others. Just a thought, good luck.

 

[94conv.]

MY 95 LT1 did the same thing for about a year. Start it up to go to store and it would run great, come out of store and it would barely idle and was down on power, did this off and on until I found a bad catalytic converter. Converter came apart and the pieces were moveing around inside it which explained why it ran so good sometimes and like crap others. Just a thought, good luck.

Thank you, how did you find it or figure it out? Wouldnt the o2 sensor see something was going on? Was there any signs thats what it was?

 

[purplec4]

Catalytic converter

When I reved the engine up there were little particles of metal that looked like gold and silver glitter that came out the exhaust on that side. I would suggest tapeing a sock or something like that on your exhaust, rev it up, turn the sock inside out and check for particles. A dark colored sock would probably work best. I had a car cover on the ground behind the car and the particles were all over the cover, I had no idea what it was until I showed my wife what I found and she said, "catalytic converter", go figure! I just remembered I had no codes or lights but sometimes at idle my air pump would come on and if I remember right it would go off when I raced the motor up, hope this helps.

 

[94conv.]

Thank you, Im going to go check it out now.

 

[94conv.]

Its running rich, alot of black on the tail pipe, I have stainless magnaflows so its easy to see but I took a blue rag and clipped over the pipes and on the bottom of the rag its got a hint of gold color to it. I tapped on the cats with a hammer, nothing to hard but I didnt hear anything rattle.

 

[purplec4]

Catalytic converter

I hate to see you throw money at a problem like I did until I found the problem. There is another way to check the cat with a digital temp gun, you take the tempture before the cat and after the cat but I don't remember what the temps should be. You could also disconnect the pipe on the side you suspect before the cat to see if it runs any better. I also did not hear any rattle from the cat but if you see gold or silver metal flakes the cat is on the way out in my opinion. I hope someone who knows more than me can help you. I was not sure if I just deleted the cat how the car would run so I had it replaced for about $175.00. We have no emission inspections in Florida.

 

[94conv.]

Thanks, Ill hopefully get it checked out sometime this week and Ill post back. I have the factory service manual but unfortunately that doesnt make me a mechanic. Does help when i have to find things on the car though. Ill be sure to leave the manuals in the car when I take it in.