Hello

Heres my situation, My car starts to tremble alittle bit after its been running for like 15 minutes or so Its weird. But it runs like a champ when Its cold!!! But to make it interesting, I just noticed some Black residue/ film on my tailpipes!!!! I'm thinking O2 sensors............but im not sure, isthere anyone outh there that might know?????? please help!

Thanks in advance

 

O2 sensors.

If they're old, they wont be as accurate, and will screw up the air/fuel ratio when the car is warmed up.

 

how much do new 02 sensors run for a 94 Z28??

shoebox: do you know a part # by any chance.......

they easy to install?

 

I think they are like $50 a piece at autozone, but you can get them at thunderracing for like 35. Dont know the # though

 

sounds like theres a chance it could be the water pump to me. LT1's are big for the pump giving out and letting small drips of water fall on to the unholy opti spark unit. this would start to happen on my last camaro 15 minutes after running it and cause it to run poor but after cooling down I could restart and run like a champ. It ended up toasting my opti and I had to replace all of it.

PS or if you have headers that run super close to wires. Sad to say I had that happen to /sigh

 

is there one or two 02 sensors on a 94

 

two.

look on ebay...the part # is afs-75.

 

Get the AC Delco O2 sensors. Part number 25312184 and you can get two of them from www.gmpartsdirect.com for $85 shipped.

Dan

 

Which sensors are those ....Can't you just get o2 simulators......... Or is that the wrong sensors that I'm talking about........

 

First off don't be worried about a little residue.........I shoot carbon/oil 6' It's probably over 100,000 isn't it? As for the stumble how hot are you letting it get? The LT1 really hates heat. If you are talking it doesn't rev as fast that is normal.........all LT1's are champs when cold

I wouldn't replace the O2's unless you check them they are probably just fine. You might want to look into the water-pump.

 

B-cuz...... I got the same **** on my exhaust tips.... And it also has a little (just a little) liquid spray/ drips coming out of the passenger side, when I REV. it up.......What is that....

 

i am pretty sure you would get an SES light if your o2 sensors were out.

 

does nobody else here look at their O2's? I was taught that if they are a light brown colour, then they are fine, if they are black, no good. No sense in replacing O2's if they're still good. I thought all vehicles have a little black carbon in their exhaust, i don't think i've ever seen a vehicle that didn't have some of that if you wiped your finger on the inside of the exhaust tip. I personally don't think the carbon in your exhaust has anything to do with your stumble. Just my .02

 

the black residue on the inside of your exhaust is the carbon from the exhaust.
The liquid shooting out is condensation from the exhaust, it's black due to the carbon on the inside of the exhaust.

 

Are u telling me that^ cause i already know......sure wish these things were'nt quite so rich stock. The stumble would be due to soemthing else.......and not the O2's prob. The best way to check the O2 sensors is to pull them out and check the voltage and compare it to the specs.