Guys, First post so please be patient. My new wife has a 96 Maxima with the 6 cylinder engine. It has 173K miles on it so I guess we should just be happy with that. It has a slightly rough idle-mostly when in reverse or drive. The RPM drops from about 750 to 600 every 5 to 10 seconds or so, but when in park or neutral it is not as noticeable presumably because it is idleing a little higher(closer to 1000). Also, it has considerable hesitation when accelerating.

I know for sure that the fuel filter is no more than 5Kmiles old, and the air filter was cleanlast I checked. Also, I changed 5 of the 6 plugs last night - that cylinder 5 stick coil boot came off and I will be fighting that battle this weekend. Still running rough with one plug still in question and soon to be replaced. I definitely do not think it is a bad injector or stick coil, etc. because it seems that it would be running much worse. I have read that the mass airflow meter can cause this and that it is a common problem. What are your opinions or ideas? thanks

 

We have replaced quite a bit of injectors and mass air flow sensors on that car.... what I would do is buy a fuel injector clening bottle that you can dump in your gastank... see if that helps.

 

If it has not been cleaned, its small wonder if sooty Idle Aadj Ctrl Valve (IACV) works at all. Clean that & TB first. (This for bad idle)

Tst disconnect MAF. Any change?

Run self diag, what does it tell? ...Knock sensor dead...?

Connectors cleanup: http://www.cardomain.com/ride/748507/14

 

guys,
I went to Autozone for the free diagnostics check and the results were bad MAS along with 2 or 3 other things that all could have been related to the MAS. I was able to replace that last plug, which did not look bad, and i removed the MAS, cleaned it and replaced it. The engine is running great now! No rough idle and no hesitation whatsoever. So, instead of a +$500 new MAS, I spent $1.99 on a can of carb cleaner and used a Qtip to wipe it.

I went back to Autozone to check again since I still have the check engine light and it shows 4 faults. One still being MAS(although I'm not sure it was the exact same fault as before), one being knock sensor, one O2 sensor, and I can't remember the 4th.

Anyway, with 173K miles and running great, I don't care about the other faults. Thanks for your help.

 

Have them clear the codes and then recheck a few days later..... see if the codes come back.

 

Take batt cable off for more that 30min =ECU reset. Its good always to reset ECU after cleaning MAF and/or replacing/adjustin any other sensor; ECU will then build new data table and compensate for new/changed inputs from the sensor(s).

It will pay back in reduced fuel costs to repair until the check engine light will go out, sensor prices 'meaninigless'...

 

Thanks Burnnout and Reiska - those are two things I had originally planned but had forgotten to do. Now I wrote a reminder for myself and will do it today.

 

[sm=welcomesign.gif]