I have a 1995 Q45t with 118000 miles on it. I have had the car sice 98000 miles and havent really had any promblems except the tranny going which i had replaced at around 110000 miles. Sice then the car has run well except now it cuts off when you come to a sudden stop or press on the breaks to hard, but it will start right back up. I was wondering if anyone else has had this prolem beofre and what might be some cuases and how does i get rid of it. All help is appreciated.

My Q had thisproblem before i came into possession of it.. Turned out to be a loose battery cable.....

Does everything cut out or does just the engine stall.....? if it just stalls it could be the IAC is dirty and cant sudenly open.....

Mine did this at 68000 miles right after I got it. It would drop the rpm's as I would apply the brakes and then it would DIE when i would come to a complete stop. I would trick it by putting it in Nuetral and accelerate.

The problem was the "Air Flow Meter".Once I changed that I was homefree.D.

Only the engine cuts, everything else stay on.

Has the fuel pump ever been replaced?Does it sound like a swarm of bees are in the trunk?What kind of maintenance has been done over the last X miles?

You're in the (high end of the) target range for a fuel pump.

unfortunatley the fuel pump has never been replaced and the back does buzz sometimes, especially when its cold. and maintance wise the belts were recently repalced along with something to do with the power steering bearings or something like that. if it is the fuel pump cold that alos be a reason why i seem to be gettin terrible mpg. i know the engine is a tirsty one but it seems to be a bit much.

Also i have been reading p a little and some have said its the camshaft angle piston sensors. any thoughts on that?

5seryan wrote:unfortunatley the fuel pump has never been replaced and the back does buzz sometimes, especially when its cold. and maintance wise the belts were recently repalced along with something to do with the power steering bearings or something like that. if it is the fuel pump cold that alos be a reason why i seem to be gettin terrible mpg. i know the engine is a tirsty one but it seems to be a bit much.

I would bet on the fuel pump too. Symptoms are identical as mine before I replaced the fuel pump. I'd get it checked into as soon as possible since it sounds like a fuel pump issue and you don't want to fry the fuel pump control unit.

someone told me that to replace the fuel pump that i also need to replace the gas tank. is that true. and how much am i looking at to replace the pump or the pump and ank if i absolutely have to. and would the best place to service the vehicle be the locla infiniti dealer. should i gets the parts from them as well. thanks for all your help so far.

You don't HAVE to remove the tank - it should just be cleaned thoroughly when you swap the pump. Here's a thread on the procedure:

zer...age=2

You get at the pump from the back seat and rear shelf.

But I'm thinking your symptoms sound a lot like MAF trouble - same thing was happening to me.

thanks 96qowner. That is a very informative post however, I have never done any work on a car myslef. I have miscellaneous knowledge that is completely useless here. i live with my parents ( im 18 ) and they would never let me try to do anything like this in their garage, and none of my friends have garage i could use. As much as i love cars, and want to learn how to repair them i have no one to help me learn and the Q seems a bit much for a first timer to tackle. So is there any definative way to decide between the MAF and the pump? and how much im a looking at for parts labor to get this stuff taken care of? again thanks for all your help so far.

Ok, well, there's something you can easily do to narrow down your problem, and that's to clean your Mass Airflow Sensor (MAF). All you need is a can of electrical parts cleaner or non-clorinated brake parts cleaner, available at any auto parts store for a few bucks.

Here's a great illustrated writeup from jesda at Q45.org:

http://www.q45.org/maf.html

If that solves your stalling problem, you're back on the road. Jesda says to use an entire can of electrical parts cleaner, but I've done mine with just a couple few-second sprays of brake cleaner. The MAF begins to fail because its "burnoff" cycle starts to work erratically due to corroded contacts in the connector, so be sure to get at the contacts buried in the connector with something skinny and sharp, to scrape any off corrosion - again, something easy to do. Put 'er all back together after letting the MAF THOROUGHLY dry out and take it for a spin.

But if your pump is buzzing, you're gonna have to replace that soon. If you don't, it'll fry the Fuel Pump Controller Module (FPCM), which is another few hundred bucks. The pump and labor shouldn't cost you much more than $400 at a decent shop. I had mine done at a Nissan dealer for that amount. If the place you take it to has not worked on Q45s before, you might print out tangalora's wonderful thread for them, and be sure to warn the tech about inadvertantly bending the float during installation.

Something else that has been discovered to cause your symptoms is temperature surges from the transmission, which confuses the ECU/TCU. I mention this because you very recently dealt with your tranny. One poster dropped his tranny pan and cleaned the filter and his stalling problem mysteriously disappeared.

But try that MAF cleaning first - cheap, fast, easy.

thanks for all the help ill try cleaning the MAF and see how that goes.

MY 94 has 110K mi. and it was doing the same thing -- would run fine down the road and die at idle when sitting in traffic or at the lights. Last night I replaced the MAF connector with a new connector and pins that I got from Joe. You cut the three wires off the back of the old plug, crimp the pins on and insert them into the locking position in the new connector. Worked like a champ. Smooth idle is back today.

This is a common problem on these cars. At idle, wiggle the AMF connector and squeeze it with your fingers from the bottom. If the idle improves or drops out, this is likely your culpret.

During the replacement I found the white lead wire to be very small --- almost "micro" wire. Hard to believe its sufficient to hold up and carry the conenction to fulfill its purpose.

Also, while you cannot easily get the pins out of the old connector, I bet they were merely crimped. Over time they inevitably come loose as years of heat and muscling the poorly placed oil filter past the connector, or bending the air filter box top out of the way, take their toll. If they are just crimped, it is no wonder they come loose. Because of the way the pins snaplock into the connector, you cannot simply re-crimp or solder the wires without destroying the connector.

I soldered the new ones within the crimps -- hopefully this will hold up better over time. Hope this helps -- the replacment connector and pins are about $20 from Joe.

be extremely reluctant to spray anything on the MAF sensor wire. It is very delicate and the shock from the blast can destroy it. Far better to fix the connector and let the designed 'burn-off' cycle do its job.