Intermittent Non-Shifting/Backfiring MAF? Help Please!

[peaceofmindinhim]

Hello,

I have been absent from the forum for awhile, as my car has been running smooth! My apologies. Perhaps this is Karma kicking my butt.

On to my problem. Over the past few days, I have noticed my car, a 1995 Ininiti Q45, will occasionally backfire (sounds like it is coming from tailpipe). In addition, there are times when it feels the car will not shift into 3rd gear. The RPM will go above 3 or 4, but the car will not shift. This is not a constant symptom. Transmission fluid levels are fine. Also, I've noticed occasionally when I start the car, the RPM will go up to 1000, and then down to 0. It hasn't done this though for a couple of days.

In the past, I had these issues, along with poor gas mileage, constant stalling, and black smoke coming from the back of my car, and the problem turned out to be the Mass Air Flow sensor. I had a remanufactured MAF installed about 3 years ago.

Could this be the MAF again? Should I clean it? Just a thought, my neighbor kid decided a few days ago (before all this happened) to give my car a wash. I didn't think anything of it, until I came outside and saw him shooting water up the tailpipe. Could that have caused any of the problems?


COINCIDENTALLY, (or perhaps not), my TCS OFF/SLIP lights come on after a few seconds to a few minutes of driving. Most often than not, the ABS light will come on as well. Here's the kicker, the ABS will work great, until the TCS OFF/SLIP lights come on, then the ABS light will come on, and voila, no more ABS.

I live in Southern California - I'm not too worried about no TCS, but the ABS worries me quite a bit.

Are these problems/symptoms perhaps related?

I understand I own a luxury car, and as such, have a responsibility to the car. But realistically, I am currently unemployed, receiving unemployment. I don't have the luxury to take the car to the dealer, and spending hundreds if not thousands of dollars to repair it.

I greatly appreciate anyone's advice. I'm willing to clean the MAF if necessary, as I've read many times people will replace their MAF when they could have cleaned it for $6-$10. Is this true?

Thank you very much for taking the time to read this. Greatly appreciated.

Regards,

Eric Jon Olsen
1995 Infiniti Q45
[email protected]

[Q45tech]

Rarely does a dirty MAF [on Q45] cause significant problems vs a MAF with solder [crystalization or migration] problems.

A dirty MAF might misinform the ecu as to the true flow of air in grams per second, but ecu double checks this vs RPM and TPS position and of course the feedbackloop from O2 at cruise..........................dirty mafs tend to show up at idle.

Probably a corroded connector or bad solder joint inside.

[peaceofmindinhim]

Q45Tech,

Thank you for your quick reply. I apologize, I am not super technical when it comes to cars - I'm learning though.

Any thoughts on what may be causing all these problems if it is not the MAF?

Thank you much,

Eric Olsen

[goody90q45]

.....Any thoughts on what may be causing all these problems if it is not the MAF?......

Pro*ably a cor*oded con*ector or b*d so*der jo*nt ins*de. (This is not a quote or copyright infringement. Refer to Q45T*chs post for the original wording)

Q45T*ch, as knowledgeable as he is, can sometimes be very cryptic in his responses but he was very straighforward this time. Please reread his post paying attention to the last sentence. What he's suggesting is to start by cleaning, tightening and lubricating the pins on the MAF connector (and the MAF pins) to make sure that they are making good contact. When you're done tightening the connector pins they should all look like the middle one in the pic. If the cleaning/tightening shows no improvement then you will have to open up the MAF and look for melted solder joints on the circuit board.

Does your MAF connector wiggle up and down more than 1/8"? Ever had a radiator leak that sprayed antifreeze in the engine compartment? Any corrosion present on the connector pins? If there is corrosion at the MAF then you need to look at the CAS connector, the sub-CAS connectors, the 2 EGR solenoid connectors, and one of the throttle body connectors. All these connectors are of similar design and are subject to the same leakage and corrosion buildup.

[peaceofmindinhim]

Mike,

Thank you for your reply. Just a side note, you didn't happen to be in Upland today did you having lunch? I spoke with someone at a Del Taco who had a 1990 Q45 - same color as yours...

Eric

[goody90q45]

It wasn't me. I live and work in the Sacramento area.

[Q451990]

Sure sounds like a MAF issue to me. That 1000RPM to zero and back up is the symptom I have experienced. You might also check your fuel pressure and volume.

Heath