bandit_601948

hi guys ! i have a 95 chevy blazer, 4.3, 4x4 ! the ( service engine light ) comes on sometimes and stays on and then sometimes it don,t come on when i am driving ! i took it to the garage and they ran a test on it and said there is no history at all in the computer ! in other words they said there are no codes at all coming up ! they told me it might be something like a leaking vacuum hose or it needs a good tune-up ! the gas cap is fitting tight so can i rule it out ? when it,s on it don,t effect the running of the car and i have power on the road but i do have a slight miss sitting and idling but not on the road ! i just bought this car last monday so i haven,t had time to work on it and the weather has been too cold ! auto zone or advance said they can,t check it because they don,t have the tester to hook up to it ! i appreciate your thoughts on this matter and thanks for your time !

spike1269

The only think I can think or would be if you have gauges in it to keep and eye on your oil pressure, not sure if it has a check gauges light or if it uses the check engine light to tell you to check them.

tymr287

If you think you might have a vacuum leak spray carb cleaner all around the intake & vacuum hoses. If there is a leak you will notice a change in the way its running.

spike1269

Well now that you say that I will have to try that On the issue I have posted on here. 4.3L help Im lost.. I will try that tomorrow as well seeing if anything changes to see if I have a vacuum leak. thanks for the Idea!!

chris537

From my experience the only time the codes come up is when the check engine light is on. it might be a fouled plug. smog pump who knows... but check it when the light is lit...

Chris537