240SX running rich

[dfw240_EE]

I have 2 questions about a 240SX running rich.

First: has anyone successfully diagnosed a rich condition using the instructions found in the zeroyon-provided FSM on page EF & EC 39 to EF & EC 44? Particularly the mixture test mode mentioned on page EF&EC 44?

Second: The CONSULT device mentioned repeatedly throughout the FSM, where can I get one?

And I forgot last night, it's a 1992, that might help on the FSM question. Kids, don't post at 3AM!
Modified by dfw240_EE at 10:44 AM 12/17/2005

[s13sr20chris]

oooh, consult...just forget that. its expensive and stuff. you can get other scan tools that are nowhere near as good though.

here are some good things to start checking. maf voltage, coolant temp sensor, and fuel pressure.

[dfw240_EE]

Well, I am pretty sure that it is not the coolant temp sensor. Recently I had the car inspected. So first I ran the car on the highway to warm it up. During the test the car ran great and passed HC brilliantly. Logically if the coolant sensor were bad then it would have run rich constantly throughout operation, since the car would think it still needs to warm up.

Now this certainly doesn't rule out a loose connection to the coolant temp sensor, or any sensor for that matter. I could have just gotten lucky and the connection was good at that exact time of test. So I think I should check all sensor connections listed on EF & EC 5-6.

I do notice that the car runs rough at idle, so I think I should run through the "Hunting Diagnostic" on page EF & EC-59 and the routine for "Unstable Idle" on page EF & EC-61 (which actually includes fuel pressure, so that's covered)

I know the CONSULT is abit much, since most repairs covered by the FSM even include "if you don't have CONSULT" alternatives, I just think it would be cool to have.

The more I look through the forums, the more that it seems chapter EF & EC (EC.pdf for the Chuki S13's) cover what we talk about. I will look through the other cases and see if any others fit my condition.

[InsanityInc]

If your car is running rich (High CO reading means rich. High HC doesn't necessarily indicate a mixture problem), the culprit is most likely the TPS. The Throttle Position Sensor is a huge part of engine management.