Here we go again - 96 Q45 MAF

[96Q45GAL]

Hello Everyone!! I need your help again guys!! I have a 96Q.. A few months ago I had issues with my MAF. I took it to a new set of mechanics because My last guy seemed to have me replace everything but my MAF. Well the new mechanics I guess tryin to help me recommended that they clean the MAF and see how it worked..Well I did that and the car was riding great for about 20mins..It got me home lets say that..I noticed it was running real good and no check engine light.I stopped at the store and when I got back in the car and started it up the RPM'S started to jump and as soon as I put it into gear it shut off!!?? So here I am right back in the same boat!! I have only drove it maybe 2-3 times since then and it runs good until you get it up to high speeds and try to come down the Rpm's jump again and when you come to a stop it will shut off then start right back up again?? run's a little rough though! Use to only act up when it was warm now it dosent matter Hot or Cold!..It has been sitting now or about 3wks not being driven at all..I start her up every few days and no matter how cold she starts right up and is ready to go but Im nervous to go:( I guess im wondering do you all think I should buy a used one which I have found or just replace with a new one?? At this point I just want the car to work!! It is paid for has 107,600 miles and don't wanna just give up on it!!! Is there anything else that it could be besides the MAF that I should have looked at b4 I spend $500 on a part and it acts up again??

[96Qowner]

Here's her previous thread:

zerothread?id=294403

I'm thinking your MAF has an iffy solder joint inside, so you'll need a replacement ... or ... your FPCU has a problem from that noisy fuel pump you had.

Check http://www.car-part.com under Air Flow Meter, either a 95 or 96 will work.

Read through Tangalora's posts about the FPCU:

Q45 fuel pump control module

Q45 Fuel Pump Control Unit FPCU

It's located in the trunk, bolted to the underside of the rear deck - easy to unbolt and look at.

[maxnix]

You would be well served to plan a trip to Mantua NJ and let Keith Vanmeter go over your car and quit using clowns to service it.

[qship96]

I agree with Brian....you are wasting time and money by using non cetified techs, or worse yet, internet clowns{us}- take it to a Infiniti dealer or VanMeters,pay ONCE to get it done correctly,and move on!

Too many times one thinks the dealer is too expensive, yet end up paying more at the local garage over and over trying to diagnose what an expert could do more efficiently with experience and the correct diagnostic tools-you are lucky having a 96 with obd2-should be easy for certified tech to get to root of issue

[96Q45GAL]

Im in the process of ordering a new one from the dealership!! I don't really wanna waste the money on a used one and have this issue a few months from now! The FPCU has not been replaced that I know of but I will have it checked.. I am bringing it in to the shop tomorrow! I normally leave it for a few days so they can take their time... As far as taking it to the Dealer..I cant take the car on the highway at highway speeds without it bucking pretty bad..and the closest dealer is about 70 miles away from me. The mechanic I have now use to work for nissan for 11yrs and has alot of experience but I guess he was trying to save me from the almost$500 part:(Question....If the FPCU is bad what issues would this cause?? I also have to get my valves sealed?? They leak pretty bad only on the left side..Didnt know if this may have played a part in the bad MAF?

[96Qowner]

Question....If the FPCU is bad what issues would this cause?? I also have to get my valves sealed?? They leak pretty bad only on the left side..Didnt know if this may have played a part in the bad MAF?

The power for the fuel pump runs through the FPCU - it regulates the speed of the pump - 3 speeds. When the pump gets old and noisy, it can draw too much power through the FPCU and heat it up, disturbing solder joints on the circuit board. (This is a different process than the MAF board, where vibration eventually destroys a joint.) The FPCU can then act intermittently, causing bucking when the fuel pump draws enough power to switch to a higher speed, even after you've replaced the pump.

Occasionally, a bad valve cover leak can drip onto electrical connectors and cause troubles, too, but I'd look at that last, in your case.

In future, you can save a lot of money on parts if you order them from Infiniti of Scottsdale, 1-888-216-5328, a NICO sponsor - ask for Joe and tell 'em you're from NICO for the discount.

[96Q45GAL]

Makes sense..Thank you..I have a ck engine light on and its throwing a MAF code!..I did replace my fuel filter months ago with a used one and the loud humming went away but noticed the car still was kinda slow? so had new plugs/oilchange/filters replaced but still seems kinda slow..wasnt like this when I first bought it? I have only put about 3500 on it since I bought it and I have had it for a year:( I swear It spends more time in my garage looking pretty then on the street:) Do you know if this FPCU is a costly part? Should I go used?

[maxnix]

Im in the process of ordering a new one from the dealership!!

A new Q45? They are out of production. No other reason to go to the dealer except for service if they employ a Infiniti Senior Technician - i.e., one who was trained on the G50 upon its introduction in 1989. Most newer techs just don't know about them and have little to no experience.

http://www.infinitpartsusa.com

will save you a lot of money on parts.

You realy need to read the posts a little more carefully. Maybe even some old ones also.

[maxnix]

I did replace my fuel filter months ago with a used one and the loud humming went away but noticed the car still was kinda slow?

Never ever use a used filter. It's like wearing a friends soiled underwear, which I am sure you would not do.

FPCU will be about $700 from dealer. See if you can find a known good one on this board in the Classified Forum under Infiniti Parts. Dealer policy is always to replace FP and FPCU in tandem to warranty them.

Last time, you really need to think about visiting Mantua. Really really think very deeply about it. Keith is a Senior Infiniti Technician. Google maps can even help you plan your trip. Even if the dealer fixes your latest problem, you need to have a proactive plan to deal with your car and what it needs next.
Modified by maxnix at 5:25 PM 3/3/2008

[96Qowner]

I have a good used spare FPCU you can have for $50, if it comes to that. Check our Infiniti Parts Forum, too, as Brian suggested - some NICO members have been collecting parts.

Infiniti Parts Forum

[96Q45GAL]

Sorry ...I meant to put used fuel pump..I had a air,fuel,oil filter put on all ordered from dealer...And like I said dealerships arent close to me and the car cannot be driven at highway speeds..due to the bucking very badly..depends on her mood:) some days I dont have any problems until I shut it off and then turn her back on or when the weather is really hot then I can forget driving her to the corner store:)Anyways thanx for the advice I definetly will check out the parts forum!!

[96Q45GAL]

I think it would be worth a shot to replace it... I definetly noticed the car got worse after I replaced the fuel pump?

[maxnix]

Something is way wrong. Make and appointment with Keith. Fill up the night before, then the next morning get in your car and drive straight there.

[Haitian_King]

I agree with Brian....you are wasting time and money by using non cetified techs, or worse yet, internet clowns{us}- take it to a Infiniti dealer or VanMeters,pay ONCE to get it done correctly,and move on!

Too many times one thinks the dealer is too expensive, yet end up paying more at the local garage over and over trying to diagnose what an expert could do more efficiently with experience and the correct diagnostic tools-you are lucky having a 96 with obd2-should be easy for certified tech to get to root of issue

Ditto on the Van Meter thing. I had him road test my Q. I was ready to pay him the diagnostic fee and he refused. I spoke with him today and he's a swell guy. We're going to speak again tomorrow and go over the prices for my work. What's great about him is that he won't increase the labor rate if you supply the parts. The condition is, they have to be brand new. He's familiar with the large volume of parts that come from IOS and asked if that's where I'd be getting them from. I said yes, and he said that he prefers their parts as it makes everything easier.

Want his number?

[Haitian_King]

Something is way wrong. Make and appointment with Keith. Fill up the night before, then the next morning get in your car and drive straight there.

That requires highway travel. Would that even be safe?

Binghamton to Mantua - 200 mi – about 3 hours 24 mins

AAA will tow (Flatbed) 300 miles IIRC before charging per mile. Now, it would suck if she brought it down, and it wasn't able to be fixed and she'd have to either have it flatbedded or driven back.

http://www.iatn.net/dir/page/i...hours Van Meter Auto Repair

[96Q45GAL]

Thats my point! I am in Upstate about 70 miles from Syracuse Ny..There is no way I could drive this thing in the condition it is in to get to NJ.. I don't even drive the thing to work..I live off of a main rd and I fear the dam thing is gonna cut off in the middle of traffic(which it has!!) I have almost been rear ended too many times to count because it just shuts off! So my only option is to work with what I got which isnt cool because I am sure I couldgo to a dealer and get it fixed right the first shot!!

[Haitian_King]

Thats my point! I am in Upstate about 70 miles from Syracuse Ny..There is no way I could drive this thing in the condition it is in to get to NJ.. I don't even drive the thing to work..I live off of a main rd and I fear the dam thing is gonna cut off in the middle of traffic(which it has!!) I have almost been rear ended too many times to count because it just shuts off! So my only option is to work with what I got which isnt cool because I am sure I couldgo to a dealer and get it fixed right the first shot!!

I agree with the Jersey drive, but there's a good chance that the dealer won't know what to do and end up just wasting your time and money. Call the surrounding dealers and inquire about Senior Techs.

Really, these techs should have a directory, or a Myspace page.

[96Qowner]

I still think the MAF is the main problem. She said when she tapped on it once, the car restarted and ran fine again, and the ECU is throwing a MAF code.

Once the MAF is replaced, we can look at the pump/FPCU.

96Q45GAL, when you get the MAF installed, ask them about having a fuel pressure test done - no big deal - shouldn't cost much labor time. That should tell you if you're having fuel pump/FPCU problems. And they can pull the FPCU and take a look at it in 15 minutes or less. They should look for char marks on the connector and/or on the circuit board inside (like in the pictures from the links I posted - maybe even print out the thread and bring it to them).

[96Q45GAL]

Thank you so much..I will be taking the car in this wk..I found a used MAF for about $100 so I went ahead and ordered it and figured if it dosent last that long then at least I can prepare for a new one:) I have a few things getting done but the MAF is my main concern!..I will tell them to do a fuel pressure check...asap! If I need it I will need that FPCU:)

[96Qowner]

I found a used MAF for about $100 so I went ahead and ordered it and figured if it dosent last that long then at least I can prepare for a new one:) I have a few things getting done but the MAF is my main concern!..I will tell them to do a fuel pressure check...asap! If I need it I will need that FPCU:)

Good Most of have gone the used MAF route and had no troubles at all with them. Put the saved money into diagnostic labor. Did you find a 96 or a 95 MAF?

[maxnix]

Thats my point! I am in Upstate about 70 miles from Syracuse Ny..There is no way I could drive this thing in the condition it is in to get to NJ..

...some days I dont have any problems until I shut it off

Difficult to predict, huh?

I am sure I could go to a dealer and get it fixed right the first shot!!

Don't be so sure. Your best bet is Keith. At least he knows the cars. Who knows who the techs are in a small town? Bet there is not a Senior in experience.

Hope you get it reliable so you can plan ahead.

[96Q45GAL]

I found a 96 MAF...Lucked up and got one from a guy who originally only had a 94 or 95 but then a 96Q came in with pretty much all good parts:) So I was able to get a cpl parts I needed now I am just waiting for them!! I will let you all know how everything turns out..I will be driving her tomorrow for the first time in about 3.5wks:( So hopefully all goes well as I head to the repair shop!! Is it bad to drive it with a bad MAF?? Whats the worse that could happen(besides bucking a shutting off here-n-there)?

[96Qowner]

Congrats on the find!

No sweat - nothing bad about driving with a misbehaving MAF, other than the nasty bucking episodes - I did it for a year, on and off, heheh. Might be bad for the driveshaft/u-joints/differential, if there's too much bucking over time, I suppose.

[96Q45GAL]

Yeah pretty much chose to let it sit because it was so unpredictable! One day it would drive great next day horrible...Or on one start it would drive great..when I shut it off and restarted crappy shut off a few times then run great again?? I am hoping the MAF clears it up because on her good days it run's beautiful!! Great car worth the save...at least i think so;)

[Denver90Q]

Have you cleaned the pins on the MAF connector yet?

[96Q45GAL]

Not sure exactly what they cleaned?? I know he said they took it apart and cleaned it with a Q-tip..They said they had it up on the highway 3 times and it was driving great....He did tell me that if this didnt work and if the engine light came back on I needed to bring the car back in and replace the MAF!

[Denver90Q]

Don't really need to take apart other than the connector and bend out the pins so they make good contact.

[96Qowner]

This is what Dan's talking about:



zerothread?id=297840

But no amount of jiggling seemed to make any difference on yours, so I'm not sure the connector is your problem. Might have your guy check 'em. Fortunately, it sounds like he's a good one - knows what he's talking about.

[96Q45GAL]

Ok I need your help guys!! As we all know I Have a 96Q with a bad MAF(I think) I keep ordering what appears to be the right used one but when I get it its wrong Well my question is when I unplug the connector while the car is in park... Is it suppose to idle a little then SHUT OFF?I think im going to order another Used MAF this week but was wondering what you all thought about the SHUT OFF?? I have driven the car pretty much daily but some days it acts Horrible shutting off at every darn light and Bucking!! Then on other days... Runs like a champ??? or when I restart it after a shutoff!!?? HUM?

[Q45tech]

As a safety measure lack of air flow [either real or a drop in 1.2 volts from MAF at idle] shuts off fuel pump after the expiration of high mode TIME [depends on coolant temp at start up ~ 5-30 seconds] to fill rails and create pressure on start up.

Turning on key create a 0.5 volt MAF signal, a running engine create a low of 1.1 volts running hot idle 750 rpm to 1.4 volts cold 1500rpm idle.

60 mph [2000 rpm steady] will be around 1.6 volts

Maximum MAF voltage is around 4.4 volts at 6000+ rpm loaded on the road at WOT!