2001 Nissan Maxima acting unusual

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First time poster but long time reader. This is a relatively long story... and unusual and please read the whole thing as some things have already been covered:

Purchased a 2001 Nissan Maxima about 2 years ago. SEL came on and had issues with staling when coming to a stop about 12 months ago. Took it to a mechanic and the MAP sensor needed to be replaced. SEL came back on and found the O2 sensor was bad which was apparently replaced with a 3rd party sensor which would still throw the code.

About a month ago while driving about 1hr 45min away the car was showing the "SLIP" and "TCS OFF" lights on and would then stall out while coming to a stop. SEL was on but would only occasionally happen. Took it to a mechanic and according to them it was a MAF sensor that was bad which they "Cleaned." Continued to happen and took it back which they responded saying they can not find the issue and to possibly take to a dealer.

It has become almost daily now that while driving I accelerate and as soon as I let off the gas it will drop below 500rpm and stall out. I looked at the MAF and noticed the resistor was missing which I replaced yesterday from AutoZone and was brand new. Read OBD code and was only a MAF sensor error. Resent it after installation and took for a drive.

Well this morning I broke down having the EXACT SAME ISSUE only this time the "TSC OFF" and "SLIP" did not come on. Also the SEL is off and has not come back on. After the stalling occurs the car has a hard trouble starting again. Sometimes it will start and then run fine, other times it will start and die right away.

No matter if I am in drive or neutral or reverse, when I hold the accelerator to 4000RPM and let go right away it will go below 500rpm and SOMETIMES catch itself and go above other time it will stall.


Any ideas to suggest? The car is now stuck in a parking lot because I can not put it into gear because the minute I do it drops to 500RPM which then it will die. I drove it for about 30 minutes yesterday after the MAF replacement and had no issues.

I do have Throttle Body cleaner which I am thinking of using tonight on the throttle butterfly but I am unsure if this would be worth it.

[loystock]

Welcome to NICO.

Have a free OBD II scan from Autozone and the likes and get a printout of the trouble code. That will help in diagnosis. Check the entire air intake - air filter (replace if dirty), check/secure all fittings and clean the Throttle Body (use rag, do not spray directly into the Throttle Body). If problem persisted and there is no trouble code, your MAF sensor may be due for replacement.

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Read 2nd post

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There is no Service Engine soon light on.I have already replace the Mass Airflow Sensor but it is still dieing out. I have read on other forum posts that "For some applications, the engine management system will need to be reprogrammed after installation of this part. " Could that be the problem?

I have connected a ODB 11 scan to it and read active data being sent and everything "seems" fine but as I said it still bogs down.

I will try cleaning the Throttle Body on Monday and see if that helps before I take it to the dealer. But as you said not to spray directly into the throttle body I am unsure how to clean it then. The tutorial on the tech page says that spraying into it is ok. I did get Throttle Body cleaner and not carb cleaner. Is there a sure fire way to properly clean the throttle body without having any issues?

[loystock]

Spray the cleaner into a rag (like an old cotton shirt) and then use it to clean the butterfly valve and body. Spraying directly into the TB can cause the fluid to seep into adjacent sensors like TPS and can damage them.

I'm still inclined to think there is a vacuum leak somewhere. But you can try starting the car with the MAF sensor disconnected and see how it goes. The ECU will use default values without the MAF sensor. It will generate error code P0100 but you can clear it. Have you checked the fuel pressure - 34 PSI with engine running; 43 psi with engine off, ignition ON (5 seconds limit)?

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Cleaned the throttle body and it was still having the issue.

I have no clue on how to find a vacuum leak. But I took it to the dealership and they told me that they can not get accurate codes. They are saying my voltages are going all over the place and I will need to rewire the whole thing. Something about my wiring harness is the issue...

I don't believe them since I would believe some codes might be thrown or jiggling the wires by the harness should cause an issue.

I am so sorry I bought a Nissan now...

[loystock]

Have you tried disconnecting the MAF sensor then starting the engine? Aftermarket MAF sensor may not be reliable and others are actually refurbished/rebuilt. Also, clean the MAF sensor connector and apply dielectric grease (available from Autozone and the likes)

To check for vacuum leak, spray carb cleaner around air intake fittings as well as around TB area and listen for engine response. If engine surges when spraying a certain spot, that is the source of leak.

You may also have a grounding issue, especially with the main engine harness. Check and clean the main engine harness ground points - near oil filler cap. Refer to grounding info starting on page EL-18 (Electrical System), in particular, main engine harness ground points on EL-24/25 from the attached link.

http://www.nicoclub.com/FSM/maxima/2001/EL.pdf

You may also have a loose connection in the main engine harness. This is true in some 4th Gen Maxima (yours is 5th Gen). Try wiggling the harness near the pax side tower with engine running and check engine response.

Another possibility is a failing alternator which can cause the car to behave erratically. Make sure the alternator charging voltage to battery is >13.8 VDC and stable (spec is 14.1-14.7 VDC).