1996 Q45 Sensor Help

[vick]

Hello Nice Q owners,

Thank you for your posts.

My issue:
For sluggishness, after reading the forums, I decided to clean my MAF! Turned out to be a bad idea. After abt 3 mo., it started stalling (and sometimes I would see "Low Battery Charge" in the onboard dash display. Short trips are bad. The worst is that my wife drives it and I do not want her to get stuck on a freeway. Plus smog check is coming up.

Anyway, took it to the mechanic, and he gave me a list of three sensors that need replacing he said.
The battery checked out ok.

1. MAF part #: 22680-61U01
2. Sensor Assy - Crank : 23731-67U01
3. Knock Sensor: 22060-30P00

Parts alone from the dealer cost ~$1,300 + labor. I am not sure what I want to do. Love the Q. Keeps going and going (despite the stalling), and still looks good.

Anyway, from a local Pick and Pull, I got an I30's MAF (did not see the year )
Part #: 22680-31U00



First, can replacing the MAF solve the stalling problem?
Second, will this above mentioned I30 part work on my '96 Q45? Should I try it? OR should I return it to the P&P in 2 days?

I will appreciate your comments. Thank you.
Vick

[Q451990]

to NICO Vick!

I split your topic out into a new thread.

I would definitely take the MAF in the picture back... it's not compatible.

Stalling could be either the Crank sensor or MAF. Are you confident in the diagnosis? I'm pretty sure the Q45 MAF doesn't have any cousins in another Nissan or Infiniti product. I'm assuming that's the case for the crank sensor either.

Heath

[vick]

Thanks Heath,

So, you suggest that I get an after mkt MAF sensor and try it?

Or, can I clean the existing oem MAF and expect improvement?
Btw, which exact cleaner should I get? I used CRC Electronics cleaner or so last time.

Thanks again,
Vick

[Q451990]

I clean them with brake parts cleaner.

Typically, if the MAF is the problem it's an issue with either the connection to the wiring harness (which I think was cured in 1995 with the updated connector design) or it's a problem internally. There are solder points where the connector solders to the board that heat up causing them to have intermittent problems. If you remove the black plastic cover on the top of the MAF, you can look for bad joints and re-solder them if you're handy with a soldering iron. If not, I'd go take my chances with a used one from http://www.car-part.com or ebay. You might find a good reman. unit as well, but I don't know of any particular brand to recommend.

check out this thread

solder-repair-maf-92-q-t405609.html

Heath

[vick]

Hi Heath,

I came across this thread...
transmission-related-to-stalling-t102297.html

What is a "transmission pan drop"? For the ignorant like me, that sounds like Greek! Transmission pan something?
Also, do you know of a page/link/video to how to open the top of the MAF?

Thanks.
Vick

[goody90q45]

It's unbolting the transmission pan in order to get to the filter to change it.

For the MAF get a razor knife and cut away the black RTV that bonds the square plastic piece on top of the MAF. Once you get enough or the RTV removed you'll be able to pry off the square cap. With the cap off you'll need a solder gun to melt the solder holding a thin brass plate that covers the circuit board and connections. When the brass plate is off you'll be able to get to the connector pins inside the MAF to melt and resolder. No need to remove the circuit board, just follow the ground circuit and resolder anything that looks suspicious. I'm no electronics guru but have repaired at least 3 MAFS with great success.

[vick]

Thank you, goody90q45.

I think I understand; if you have a pic (or point me to one), that will give me confidence in attempting!
Heath: I just returned the I30's MAF back to the shop. PPl at the yard said that they have two 1994 Q45s (VH45DE) in the yard. Will an MAF from one of these (if I get lucky) fit my '96Q?

Also, approx where are the Knock and the Cam Posn sensors (that I wrote in my first post) located (just in case I want to get them)? I have never opened anything in the engine other than replace an air filter, change oil, throttle body cleaning/MAF cleaning.

1. Is it even doable (getting these sensors out of the '94 cars from the yard)?
2. Is it even worth getting these used sensors for my Q?

Thanks guys,
Vick

EDIT: From browsing on Ebay, I gather that the MAF from a 1994 will not work since that part # is 22680-61U00; mine is 22680-61U01.

[nuuBeeq45]

I did the re solder of the 3 connections on the diodes on the MAF sensor,that kinda helped. Wish there was a resistance /capacitance set value that could fool the ECM with the knock sensors.This thing is a nightmare with all the sensor crap,im about ready to apply Tri Nitrol Toluene to the thing and call it a wash.

[vick]

Standing on the shoulders of you giants! That is what I finally did! Mustered the courage to open up that MAF sensor. Found one bad solder joint, I think (see 3rd pic, 3rd joint from the left edge). Pls tell me if I am wrong.

For ignoramuses like me, I took some pics (in the order shown) so they too can fix their MAFs. As you can tell, I did a poor job soldering (the third one from the left edge). The verdict is not in. Q did *not* stall during the 2mi test drive (but it has been known to go for days without stalling despite the MAF problem).

But, the Check Engine light is STILL on! I need to get rid of it before I can go to the smog center.

Whether or not this works, I will report in a few days. But thanks to the contributors above for the info.
Vick

Tools:
A screwdriver (to loosen and remove the MAF from the car)
A small screwdriver from a watch repair kit (to pry the top of the MAF open)
Utility knife to cut the rubber seals around the top (you can leave the right or the left side uncut, so the top opens like a lid to the side)
Soldering gun + some lead
Paper towels, a magnifying glass will help.

Time Reqd (For me): About 2 hours.

Cost: $0 (vs. new sensor: $200-$550)





Gently, using a screwdriver or some flathead tool , from the front, lift the thin brass sheet held in place by a solder at the back. You do not have to remove the sheet completely. Don't lift and close it too many times since the joint might fail and you will have to do one more solder!





Results: Did this on Monday night (Oct 28). As of today (Oct 30), there has not been a single instance of the engine stalling. Will report end of the week. The check engine light is still ON.

[vick]

Ok, here is an update: The bucking/jerking problems went away for 3 weeks (only one instance of stalling). However, the engine drops the rpm almost to zero in Reverse only.

I also did the "transmission pan drop" -- or a simple transmission fluid change.

Be that as it may, I reset the codes, then after a week, it came back (just as I was getting ready to get it smogged).
Then, found out that one of the codes was a P100 (MAF sensor circuit something). I knew immediately this had to do my solder (see prev post). So, I took that solder on the third post out, put it back in, reset the codes.

Now, it came back with "P0325" or something -- Knock sensor. In the not too distant past, I have seen a P0340 (cam position sensor or something).

The question for me is: How much will it be to replace the two Knock sensors + harness + whatever else? Is it even worth it? Can someone pls weigh in? Thanks.