Hey, I bought a 1990 gs about a month ago with 130000 miles and the engine was rebuild about 30000 miles ago, exept the car was sitting for around two years. The car and everything started fine and ran pretty good when I got it. So i changed the spark plugs, the wires and all the basic mantinece, I also bought a cold air intake for it since the stock one was bad. After I put all the new stuff on i ran it for a while and every time I punched the throttle hard, it sounded like it was bogging down and the RPMs would just stay the same but then it would start to rev up normally. Also I took one of the plugs out and just after running it at idle for 10 minutes, it was already very dark. So I was just wondering what could be causing this, or how I could change the air/fuel mixture so it doesnt run so rich. Any help with this would be appreciated, thanks.

 

Check your coolant temp sensor, if its bad it'll tell the pcm to add more fuel-rich..

 

If that temp sensor is bad and I replace it would the mixture correct itself on its own or would I still have to change something with it?

 

It should fix itself, I had the same problem, but my issue was on start up and my plugs were blk.

 

Okay I will try that but where is the coolant temp sensor and where could I buy a new one from?

 

yea, before my car blew up the coolent temp sensor went bad and it did the same thing

 

oh, and it is unter the thermostat where you put the water in the radiator.. and you can buy one from advance auto for like 20-25 bux

 

Ok Ill try that, thank you

 

Reset the ECU. Remove the negative battery terminal for about 20 seconds, put the key in the ignition to drain any excess power and then reconnect it.

Also, what kind if spark plugs did you put in? Are they gapped correctly?

 

I put in Bosch plugs and yes they are all gapped right. Also the new intake that I put in, could that have anything to do with it?