95 Chevy Blazer Engine Light

I have a 1995 Chevy Blazer with the 4.3 Vortex in it, over the past couple of months or so, my service engine soon light has been coming on and off, it would come on for about 20 miles or so, then it would go off for about 200 miles or so. I had two of the lights diagnoced, and they came back with nothing wrong. I was wondering if anyone has any ideas of what could be causing it. Thanks

So you had it hooked up to a scanner?

No codes at all?

If the light come on, there has to be a code.

take it to Autozone or one of those places and ask them to read the codes. They will do it for free. Report back to this forum with the exact code (ex. P01750). Ask the people at Autozone to use a code-scanner than will detect the "history codes".




I have a 1995 Chevy Blazer with the 4.3 Vortex in it, over the past couple of months or so, my service engine soon light has been coming on and off, it would come on for about 20 miles or so, then it would go off for about 200 miles or so. I had two of the lights diagnoced, and they came back with nothing wrong. I was wondering if anyone has any ideas of what could be causing it. Thanks

The service engine light will probably have to be 'on' to be able to pull a code.

Autozone says that they cant connect to my reader thing, that they have to use to gain access to all that information. And i have had it checked when the light is on, by my local chevy dealer, and they sayed htye didnt have a code return.

Make sure all the connections are tight on the ECM.

Is your ECM on the right fender or in the dash?....you might have to pin it.

I am withBlazee on this one. My truck threw a code for a non-operative EGR valve in recent history. But the guys at Autozone could not pull the code at all. On my 95 truck, with the ECM under the dash, I had to take it to a garage with a specialized tap that would fit the 16 pin dash connector, but then had a pin card inserted to "rewire" the right pins to read the computer codes from the older OBD-1.x style computer. 95's a *bastard year* to pull codes from. Looks like an OBD-II computer connector, but it speaks a very arcane language if the computer module's inside the dash instead of on top of the coolant overflow tank under the hood. Take a peek under the hood and see if there is a big silver/black hunk of metal with wires coming out of it with fins on it's body right there in the passenger side to the left of the A/C condensor. If you just see the coolant overflow tank, then your computer's under the dash and it needs to be tapped out with a special reader to pull the codes.