I've had the car for three days now. Today was my first trip on the freeway with it. It was the first time I was ablo cruise. I was going for about twenty miles and I put it into 6th gear. After I put in at six I noticed the car began to lose power for a split second ever few seconds or so. Some instances would be rougher than others. I noticed the check engine light would come on every time after the skip happened of it would just stay on. So, I pulled over, cut the engine off, checked the oil and went back out. I drove 70 more miles to Fayetteville with no sign of a SEL and haven't had any problems all night. What the heck is going on?

 

Kinda hard to guess without more info. Try taking the car to Autozone or Napa or something and get them to scan the computer codes next time the light comes on. They usually do it for free and you will know what's wrong with the car instead of 30 people here making guesses as to what could be wrong.

 

With a question lik this, you might also want to post little details like the year of your car, tran, any major mods.... makes it a little easier to "guess", since not all years are the same.

If the light came on, the code is still stored in the PCM. A scan would answer your question.

 

I don't think autozone does it before 96 models. Do I have OBDII? And if so, where is the diagnostic box on these cars. I had a probe before and I was able to run the codes on it without a scanner.

 

Yes Autozone can run a scan on a 96 OBDII.

They can not scan a 95 fbody however but you should be fine.

The only way to get codes on your car is through the Diagnostic link connector under the dash. A scanner, laptop ect ect hooks to it and comunicates with the PCM and reads the stored codes.


oh and yes autozone will do it for free

 

sounds like a missfire. or the computer sensing knock, and it was retarding the timing.

 

It hasn't done it for two days now, but what would cause a misfire or knock?

 

Your 1995 is OBD-I. It does not have misfire detection, and there is no code in OBD-I caused by knock (yes, there is a code for a faulty sensor, but not for knock itself). So those problems are not going to show up in a scan.

Get it scanned. The code will only stay stored in there for a while, then clear itself. "Guessing" is not the way to solve the problem....

 

When you say the code will stay there for a while, do you mean it will never come back even if the problem persists? Ex: If my O2 sensor went out and I got a code for it today, would it go away and never come back even if I still had the problem?

 

bet you its the egr valve. thats the only time it will be used is on light cruise. and, if its not working, it will cause loss of performance and most times you can feel it. depends on if the valve is sticking open, or closed.
and, my 95 has the OBDII conn. on it, even though it is still OBD1. if your diagn. port is a perfect rectangle, then it is the OBD1 port, if its wider on the top then the bottom (as in more terminals), its OBDII like mine. if so then they should be able to scan it.

 

Ok.... let's go through this one step at a time.

The PCM runs a diagnostic routine and sees a problem.

It turns on the SES light, and stores a code for that problem in volatile memory in the PCM.

If the problem goes away the SES light goes off, but the code stays stored in the PCM until A) it is cleared by using a scanner, or pulling the power to the PCM; or B) the car is operated for a specified number of drive cycles - let's use "50" for the number of cycles, in this example - without the problem happening again.

The code will be set EVERY time the problem occurs.

The fact that it is stored in memory has absolutely no effect on whether the problem can happen again, and does not prevent the SES light from coming on if the problem happens again.

Can't quite follow how you interpreted anything I said to mean that the code "would go away and never come back even if I still had the problem".... that would make no sense at all.