'92 Q: Hesitation, bucking, complete engine stop,then normal, no CEL

[kdkrone]

'92 Q, 130K miles, well-maintained, especially last 40K by Jerry Tucker before he retired.

fuel injectors all replaced between 96 and 120K miles with harness at 120Knew fuel pump 113K (prophyllactic) Jerry tested the fuel pump controller and it is fine.new fuel filter about 15K agochain guides, oil pump, fan 87Kfuel lines 95K and 127K (mouse chewed through one recently)knock sensors at 120KOEM Plugs at 96KO2 sensors not replaced, per Jerry's advice.

Now, increasing episodes of rapid sudden loss of complete power for a split-second, then no normal, happening when engine warm or just started. Once, I had just started the engine--died quickly with a message that the battery was low (I have learned that when this happens, random messages may appear, including, on one occasion, the message that the rear tail assembly was non-functional. The car started about 30 seconds later with no problems). At the time, the headlights were on and did not dim. I shut off the engine and it started right up, making it home with only one episode of split-second loss of power on the freeway at 70 mph. This is not a missing injector---I have lived through injector misses and this is not it. This is complete loss of power and probably electronic, although I suppose fuel is a possibility...

Yesterday, the problem was worse. After running a few miles on the freeway, the car lost complete engine power for a split-second and I pulled off to run an errand. On my way back onto the freeway, the car died completely twice (I was able to coast to the side and restart quickly after I was stopped. On the way home, at speed, the same loss of power occurred, a little bit longer this time, so that when the engine kicked back on, there was bucking as the engine and transmission matched their speeds. The car is now in my driveway.

I have read the threads on hesitation and plan on checking connections, annointing them with Stabillant 22 which I bought and used a couple of years ago. It sounds like it may be the MAF connector or the CAS (where is the connector for that?? I am sure it must be in the FSM). I will check for codes in the ECF, but no lights have gone on (CEL?). Where else might the culprit be? What other info would help? I am just trying to "pre-think" this before I get at it on the weekend.

ThanksKen K

"When she is good, she is very, very good, and when she is bad, she is horrid....!!"
Modified by kdkrone at 8:09 PM 1/15/2009

[96Qowner]

Classic symptoms of a bad MAF.

It would be one of two issues. Either the connector pins have wiggled themselves loose from their wires, or the internal circuit board for the MAF has solder joint failures.

Several members have pulled the circuit board and fixed their MAFs by resoldering the joints. If you're inclined to try that, there are old threads on the subject. Take a good hard look at the connector first.

[kdkrone]

Well, that was a fast response!

The connector was my first check point. Where is the circuit board? Any tricks to getting to it? As it happens, I purchased a spare MAF about 2 months ago, so that may be a blessing in disguise.

With some luck it will just be this piece of equipment and I will be able to get safely back on the road.

Thanks for the rapid response.

Ken K

[96Qowner]

You get to the internal board by cutting the silicon seal on the square cover and carefully prying it out, exposing the board.

If your connector is fine, you can isolate the problem by swapping in the spare MAF - really easy.

And you're welcome - it's a slow day at work.

[kdkrone]

I am at work, as well, so I can't see the MAF. I assume that there is a square cover mounted on the MAF and it is that which I carefully remove. What is the trick to securely replacing the cover?

ThanksKen K

[goody90q45]

A bead of silicone adhesive. No different than caulking the bathtub.

For now swap in your spare MAF and see if the problem goes away. Tighten up the female pins in the connector if it's loose at all. If your MAF is bad there's a few posts on repairing MAF solder joints to make them work like new.

[kdkrone]

Thanks, Mike. I need you as my neighbor!!!

I don't know what the weather has been in Sacramento, but the coast has been incredible. I feel terribly guilty about it, however, when I hear about the rest of the country... ;-)

Ken

[goody90q45]

fuel lines 95K and 127K (mouse chewed through one recently)

Oops. Just noticed this. Is Mrs. Mouse building another nest at the expense of your injector harness? The voodoo mouse head you left dangling under the plenum didn't scare her away? Better check under the plenum with a flashlight just to rule it out.

Send rain to NorCal before the lakes dry up.

[kdkrone]

No nest. That is the only thing I have had time to check. Those symptoms, however, were just the smell of raw gas and a slight decrease in gas mileage, but it certainly occurred to me. I am no longer mr. nice guy, parking my car at the end of the cul-de-sac adjacent to the open area of the canyon. My car has been parked on the driveway to save the painful cost of having someone pull the plenum to replace a $2 hose....

[kdkrone]

WRT soldering technique: I have not soldered since I was a kid and that was many years ago. Which type of solder should I use? (I remember acid core and resin, but I don't recall which is used in which circumstances. I am willing to dust off my equipment, if I can find it..!)

Ken

[maxnix]

Ken, you might look up old member 911/Q45 as he is there also.

He might like to look at a G50 as they traded his mom's 1990 in on an Odyssey.

[kdkrone]

He is on the central coast near San Luis Obispo?

[goody90q45]

It looks like he's in SLO but hasn't been active on NICO for a few years.

zer...id=48

[M45Caliber]

My 2003 M45 displayed the same effing driving and starting characteristics as you've described. One time it did it (cut out) and I was driving past the Infiniti dealer. I flipped a U, they Coded it and it was the crankshaft positioning sensor.

I had no CEL either on the multiple times it happened prior -- until that last episode, which was why a pulled into the dealer - the CEL light FINALLY came on.

Replaced under warranty (my M was purchased in Cali when new, so it falls under the much more strict Cali smog laws, hence Infiniti fixed for free) - otherwise it was a $400 dealer repair.

Not ONE drivability problem since that was replaced.

[kdkrone]

Very interesting!

I will check the codes tomorrow.

So how do you like your M45? I have been thinking about what I would purchase whenever I am finally finished with my love-hate relationship with my '92 Q... The closest Infiniti dealer is in Santa Barbara, about 90 minutes away.

[M45Caliber]

M45 -- LOVE IT. The Original Japanese version of the Chrysler 300M Hemi - only better. Read all the threads in the M45 forum; on the '03's there were some engines that burned oil, so be sure to find one that's been serviced and taken good care of. I get compliments ALL the time at gas stations and restaurants. Last week I guy asked me if it was the new '09, as it looked so different from the '06-08's. I told him it was the PREVIOUS model to the current version, and he was amazed as he thought mine looked MUCH better that the currrent ones. I can't comment on that (eye of the beholder -although I would agree...) but I can tell you you will never have to worry about seeing another one in a parking lot when you go somewhere. These things are RARE!

I'd go with the 2004 model given the engine issue with the 2003's and the major fact that Infiniti moved the CD changer to the dash and placed the cassette in the glovebox - the 2003 was the opposite.

Prices have dropped like a rock over the past 12 months so you can find a clean low mileage 2004 for around $12K - if you do your homework and negotiating. LA has the biggest concentration of these, so you have a good hunting ground should you go looking. Good luck!

[kdkrone]

OK. First thing I did this AM was to hook up my Blazt cable and diagnostic program. Fortunately, one episode of my three difficulties in starting (tried to start, immediately died with error messages like "Tail assembly inoperable", "Low Battery", then started right up) was captured with the error message:Error 12> MAF circuit. I stopped the car and took off the MAF connector. For kicks, I started the car and was surprised to see that it actually ran without any problem---what is it that the MAF actually does? Anyway, I applied Stabilant 22 to both sides of the connnects and cleaned with a Q-tip and a little scrub stick supplied by the Stabilant people. I cleared the ECU memory and started the car. I queried the Self Diagnostics and it gave me a Code 55: no errors. So, fingers crossed....

Before I swap out the MAF with my spare, I will drive around the neighborhood, and if the beast has not hiccuped, I will try a run on the freeway. More later...

(For the future, where is the CAS located (I can't tell from the diagram in the FSM) and is it a part that dies or just the contacts? Do I need access to a lift to get at it?)

M45Caliber, my main concern is with service, although there is a Nissan dealership in town...

[96Qowner]

While I've replaced my CAS, my understanding is that it usually doesn't fail - the internal contact points just get dirty and fail to sense the full 360 degree cycle. Even more common is a bad/dirty connector like the MAF. Nissan refers to it as the Cam Position Sensor (CPS), located at the bottom front of the motor. In any case, nothing special is required to replace it, if necessary - easy to get to.

[kdkrone]

Thanks for chiming in, 96Qowner

Is the cleaning of the contact points of the CPS something that is easily done? Perhaps worth doing prophylactically? or is the best thought "if it ain't broke, don't fix it....."?

Also, can anyone chime is as to what needs to be done to replace it? Is it something that can be done on jack stands with a socket set, or does it need some higher-tech tools and special adjustment after it is replaced?

[goody90q45]

There's nothing wrong with your CAS that would warrant replacing it but it is worth cleaning the connector and tightening the pins. Unless you have skinny proctologist arms and hands you'll need to remove the airbox lid and then the airbox base (four 10mm bolts) to give yourself some room to work.

With the base removed it will be easy to get to. You'll see the CAS mounted on the front of the engine on the DS block above the oil filter and below the DS plastic engine cover. It has the same connector as the MAF and its wiring comes off the main engine harness (large bundle of wires). You know the routine. Remove the metal clip and pull off the connector. Clean, tighten and lubricate the connector pins and CAS pins. Reconnect ensuring a good tight fit. If you have corrosion on the CAS connector you've got to assume it's on the subCAS (2 ea) and and injector connections and should clean those while your in the mood.

[kdkrone]

Well, three days of no problems and counting...!

Many thanks to those who helped me through what turned out to be a relatively innocuous (and inexpensive!) problem. Cleaning the contacts seems to have done it. Not time I have some time, I will go after the CAS contacts.

Much as I enjoy driving this car, I don't think I would keep it without having this forum as backup. The help I have received is invaluable, especially over the years from Mike G, who, in addition to providing invaluable information, also convinced me to purchase the Blazt cable and diagnostic software (now if I could just remember to use it...!).

Thanks again,Ken
Modified by kdkrone at 9:33 PM 1/19/2009

[kdkrone]

Well, after a few days, the problem recurred. I finally had some time yesterday and replaced the MAF. Seems to be running like a top, but we will see.

I am going to play with the MAF, and will start a separate thread about that now. For posterity, I will add to this thread as either positive or negative problems arrive.

Ken