My car stalls sporadically

ANONYMOUS

MEMBER
1996 NISSAN MAXIMA
21,000 MILES

My car stalls sporadically. When I rev the engine black smoke comes from the exhaust. I can also smell the exhaust in my car. I have had the whole exhaust system replaced including the muffler. Occasionally it will lose compression and will not accellerate, causing me to pull over to the side of the road and wait. I can usually turn it off and wait 5 minutes or so and it will then accelerate and I can drive away. What do you think the problem can be?

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

The random engine stall could be due to a faulty crankshaft position sensor.
The crank sensor sends the signal to the ECM of the engine revolution. Over time heat and vibration from the engine can make the sensor lose its internal calibration. This will trigger the sensor to send incorrect data to the ECM. That can lead to engine stalls.
The crank sensor is located on the lower part of the engine on the right-hand side (if you are facing the engine).

https://www.2carpros.com/articles/symptoms-of-a-bad-crankshaft-sensor

Black smoke out of the tailpipe can be due to a number of reasons. It could be for a bad oxygen sensor, failed fuel pressure regulator, bad EVAP canister, defective EGR valve etc.

Here is a helpful guide:

https://www.2carpros.com/articles/engine-black-smoke

I have attached diagrams for your reference.

Please let me know if you have any questions.
Thank you.

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