Ravintommy

Hi, I have a 87 stock Max. My Maxima got hot about 2 weeks ago and after that I had to replace the alternator. But ever since it got hot, it wont go over 2000 RPMs. Its like the fuel is cut after 2000. I checked computer codes and it said the air flow meter circuit was malfunctioning so I replaced the air flow meter. It still doesn't work. Has anyone had this problem or heard of it.

Nismo87SE

Your car is in fail safe mode. 2 things will cause this a bad MAF (mass air flow meter) and/or CHTS (cylinder head temp sensor). Now if the ECU is still giving you the code for the MAF circuit not working. In the service manual there is a procedure to test the MAF's output. I suggest you check the wiring from the MAF to ECU and the fuses too.

Ravintommy

Where is the Cylinder Head Temperature Sensor located. How do I reset the computer. Thanks Nismo.

Nismo87SE

The CHTS is located on the right side cylinder head about 1" below the timing sprockets. You should see a connector that is just above the timing belt cover that leads under the cover. It is the connector to the CHTS. To reset the ECU you need to select mode IV in self diagnostic then select either mode I-III again. This will erase all previously stored codes.

Ravintommy

replaced chts and air flow meter, still no good
help, I dont have any ideas and I have looked through my book for hours trying to find an answer

Nismo87SE

There are 3 things that cause the fail-safe mode, MAF, CHTS and fuel pump. Do a mode III and V test on the ECU. I'm willing to bet that your fuel pump is dying. If you do find out that it is bad you can replace it. However I suggest getting one from a 87-89 300zx turbo, since they are the same price but it will flow more fuel.

Ravintommy

ok, cleared the computer. and ran both tests and its still saying the air flow meter is malfunctioning. I bought a used air flow meter, maybe this is the problem. dont know anything else that could cause the air flow meter to malfunction?