so is there a way i can adjust the fuel mixture???? or is it just controlled by the ecm? my 91 tpi is running extremely rich. i think it could be the reason it is causing it to run rough at high rpms? i really dont want to look dumb and take it to a shop when i can do it myself. any suggestions...also i have replaced my distributor would that have anything to do with it if its not running right?

 

It could be a number of things. I would do a search here on "running rich" and "checking injectors" and read whats been posted. I would suspect you may have a leaky injector(s) or maybe a leaky fuel pressure regulator. Are you getting an SES light, throwing any error codes?

 

How do you know it's running rich? You smell gas? Check your timing first!

 

know much about the service history on the car? As O2/ lambda sensors are so cheap, I normally change these out as routine on buying a used car and have always noticed an improvement in running/ mpg.

also as above, check the injectors by pulling out a mulit-meter and checking the ohms of each injector. I forget the tolerences but do a search and you should easily find it. I have one low ohm injector and that is causing a rich condition (as verified on the dyno) and drivability issues

 

CTS may be causing you problems... itself or wiring...

 

I would definitely start by testing the CTS. It should read about 3,400ohms at 70 degrees(cold engine), and 180 ohms at 220 degrees (hot engine). Also, pull the hose off of the fuel pressure regulator and look for fuel in the hose, coming from a ruptured regulator diaphram.

One tool that I find pretty much indispensable when diagnosing any EFI car is a compatible scan tool. The scan tool lets me see data from each sensor as the ECM sees it. This can save alot of time chasing down a sensor issue. As we develop more diagnostic experience, information from the scan tool can also help us find many issues aside from faulty sensors.

 

If you do decide to check the resistance on your injectors be sure to do it
when the injectors are warm and cold.
A quick way to check for leaky injectors....run the engine for a minute or two, then pull the plugs. If you have wet cylinders you have leaky injectors.