90 240 Running rich

Running really rich and hot. O2 sensor is fine (had replaced a few months ago and both new and old don't solve the issue). Fuel pressure is fine. Injector noise has increased. Checked AFM connections and temp sender connections. No codes. What's next?

AJS

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AJS
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If the engine is running very hot the fuel injection goes full rich to with full advance to protect the motor. Why is the motor running hot? No coolant? Low coolant? Head gasket leaking? Restricted radiator? Bad fan clutch?

Bob

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User

It's seems to be running rich and THEN hot. So rich from idle on a cold motor.

Well that's the thing. Symptom or cause? Thermostat seems to be working correctly but will be replaced anyway..

Coolant is fine. I flushed and replaced when these symptoms occurred just to be certain.

Nope.

AJS

Reply to
AJS

:> If the engine is running very hot the fuel injection goes full rich to :> with full advance to protect the motor.

: It's seems to be running rich and THEN hot. So rich from idle on a cold : motor.

:>Why is the motor running hot?

: Well that's the thing. Symptom or cause? Thermostat seems to be working : correctly but will be replaced anyway..

:> No coolant? Low coolant?

: Coolant is fine. I flushed and replaced when these symptoms occurred just to : be certain.

:>Head gasket leaking? Restricted radiator? Bad fan :> clutch?

: Nope.

: AJS

may be a ridiculous idea, but check the distributor cap. a crack may misfire on one-of-four (always or intermitently)... causing overheating an apparent rich-mix... it happened to me once... it was real puzzler btw. it the catalytic converter also running hot? that's a hint...

Reply to
AND Books

There is no doubt it's running rich :) the best I can get is 350Km's from a tank VS getting 450 with hard driving.

AJS

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AJS

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