I have a 92 maxima GXE. Last week, I noticed it was very slow to accelerate from a stop and also while I drive it seems to get into a jerk/surge mode as if the vehicle is being pushed back and forth. The acceleration is very sluggish and RPMs staying around 2500. I stopped an pulled the codes and I got a 12 (MAF) and 43 (TPS).

The car starts up fine and idles fine at around 900-1000 rpm. I don’t get a feeling at any point that the car is going to stall when I am stopped at a light. It’s only when I put it in drive or try to accelerate that it is very slow to react and move forward. This slow response is right from when I start the car (i.e. dont have to wait for car to warm up). Then, the symptoms get progressively worse and erratic after about 20 minutes of driving and the car begins to surge and jerk and very very sluggish gas pedal response.

From the research I have done on this forum it appears to be a MAF symptom. However I am confused that it is also throwing a TPS code. I was wondering if the TPS code is being thrown as a side effect of the MAF issue.

I also checked the transmission fluid and it looks and smells fine. No particles. I don’t see the transmission slipping per se when I have this issue. Had it been transmission I suppose I would have seen a gradual slipping or degradation over time. But nothing of that sort.

Things I have tried:

MAF:
I measured the output voltage on the MAF and it seems to be approx 1.3V at idle and goes up steadily as the RPM is increased. This reading seems to be within spec. But I took this reading about 5 min after warm up. The surging symptom only starts after I have driven the car for about 20-25 min. So I suspect the problem may not have manifested itself when I took the reading. I also tried cleaning the MAF with CRC cleaner. I changed air filter. It had been a while since I had changed it and it was kinda black. The CRC cleaner did not seem to make any difference although I gave it a good clean two times

TPS:
I did the resistance check on the TPS throttle switch the resistance smoothly increases between 900 ohms to around 7000 ohms (WOT) as the throttle is pressed. But it does not go up to 9000 ohms WOT as stated in the FSM. Since the TPS is a potentiometer I would think it can short or open, but for the resistance to go down from 9000 to 7000 ohms does not make sense. Or is it because of a throttle cable issue. I even tried manually moving the throttle on the throttle body but still max resistance is 7000 ohms. I have not performed the voltage test on the TPS. The voltage check is with the TPS connected. So I have to tear open the rubber connector to get to the TPS terminals. I was not sure if there was a better way to get to the terminals so I have not done the voltage test.

At this point I am unsure which component is the faulty one - the MAF or TPS or both. It is unlikely that both failed. Maybe the TPS just needs adjusting and the MAF has failed?

Another question is whether I should buy aftermarket products or should I go for used OEM products. From what I have researched OEM is always recommended. But the new OEM MAF is $400+ and new TPS is $159 at courtesyparts.com which is very expensive. Ebay has aftermarket (new) and used OEM products under $100 for both parts. Could you please advise on this as well.

Thanks for your help and suggestions.

 

Does the engine rev up all the way in neutral? Or does it have an artificial "rev limit" at 2500 or like it does while driving?

TPS and MAF are totally unrelated, so it's not likely that one 'caused' the other.

 

Thanks for your response. Just tried it. The engine does not seem to rev beyond ~2500 rpm. It seems to hit a hard stop there

 

then the ECU still can't read your MAF. As far as the ECU is concerned, your MAF is unplugged. The hard stop is a fail-safe.

 

I reseated the MAF connection and tried again. It does seem to rev over 2500 now. However, in drive I have considerable lack of power.

 

I had the MAF clip removed from before when I was testing the MAF voltage. The connection appeared snug but there may have been a loose contact. I pressed it back in just to make sure.

 

does the trans appear to be stuck in a single (high) gear, or is it actually shifting between gears as you go? This is what "failsafe" mode looks like (my speedo was reading 1/3rd of actual speed... 15mph = 45mph, i replaced it later)

 

failsafe = 3rd gear only btw. I'm not sure if shifting from D to 1/2 overrides this or not... my car's not auto anymore since I did a 5spd swap (like a week after taking that video lol)

 

I just drove it again to make sure. When picking up speed from a dead stop, it needs extra gas pedal effort to get it moving (if the car were a stick shift, it would seem like I am trying to start in 2nd or 3rd gear). The revs go up to around 1500 rpm before the car really moves. Once the car moves it appears to be shifting through gears ok but acceleration is slower as if there is some sort of resistance. It does not look like the transmission is slipping. E.g. I press the gas pedal and the revs go up to 1500 rpm but the pickup in speed by comparison is very slow. I am afraid to just floor the pedal.

On a slope, from dead stop it again feels like I am trying to start the car in a higher gear, there is very sluggish response. The car does not move forward with the press of the gas pedal as it normally should. It begins moving slowly when RPMs reach around 1500 or so and slowly climbs up. But acceleration response is very sluggish.

When I have driven for about 20-30 min, then I see the jerking problem where the car does not move smoothly. It is as if the car wants to stall but it does not really stall. This problem is different from the acceleration problem that I see when starting from a dead stop.

To really summarize, the issues in two sentences:

1. Sluggish response when starting from a dead stop. It is as if I am starting a stick shift in a high gear
2. Sluggish acceleration and a feeling of stalling when doing normal driving Problem is noticed after about 20-30 min of driving and not at the beginning. RPMs stay around 2000-2500 rpm. Transmission does not appear to slip.


I hope I explained it as best as I could

 

Shifting from D to 1 or 2 does not seem to make a difference

 

that picture i posted was actually a link to a video... see if you can watch it, and if it seems similar to yours (just remember i had a bad speedometer, so by the end of the video i was really going 40mph..... and in the video i had it floored)

 

Thanks again for your continued help. I clicked on the image but it appears to be a photo. Was there supposed to be a link to a video? In my case, the speedometer does seem to be working ok. There is some sort of a performance issue but I cannot put my finger on it. FWIW, I have ordered a used MAF. I will see if it makes any difference and post back what I find.

 

this is the video link. http://s164.beta.photobucket.com/use..._1165.mp4.html

i'm actually on a computer.... phone results may vary.

Also I'm not suggesting there's anything wrong with your speedometer - i was merely stating to keep in mind when you watch my video, that the speed is about 3x what you see on my needle, to judge if your car was doing the same thing mine was. Granted mine was induced... not the result of an actual problem.

 

My VG had a fuel regulator go out and a few injector harnesses come unplugged back in the day... stumble, sputter, over accelerate.
Not to mention the cap/rotor assembly can become wet and or clogged as it is mechanical a unit. Once a year I had to clean off the contact points inside the cap.
Sticking or clogged throttle body caused some over revving at idle as well.

 

He didn't say his car was misfiring or idling high.... sooo.... http://en.wikipedia.org/wiki/Price_of_tea_in_China

I'm betting his trans is in failsafe mode right now, which is causing him to start in 3rd rather than 1st (crappy takeoff/acceleration)

 

did your new MAF arrive yet? trans still shifting poorly (or not at all)?

 

Checked your knock sensor recently?My wifes 4th gen had sluggish pedal response and jerky,jagged RPM increase.

 

I had something like that happen about a year ago. It always felt like it would stall, at any moment, I hated stopping at lights, and then when I hit the pedal it would be sluggish and then sometimes suddenly take off in jerky type motions. Like my car was possessed. Eventually it stopped running altogether,

I took it to one mechanic (master mechanic) and he couldn't figure it out -- said I may need a new transmission, etc. I was going to order one from the junkyard but didn't think it was worth it to spend money on this car.

So, I took it to another guy, and he took like a week or so, but he finally said he saw a bulletin Nissan issued about grounding the MAF? or something like that.

Anyway, it has been running since then on the used MAF he put it, and the grounding? wire. And I have had no problems. Smooth acceleration -- though it revs to higher RPM's then it used to before shifting, don't know why....

 

power/comfort switch different position? Did the mechanic fiddle with your TPS calibration at all?

 

Hi CapdedCadaver,
Sorry my MAF (used one) arrived but I had to go out of town so could not try it out until now. I just tried it out today. But it still does the same thing...the surging up and down. I am not sure it is the MAF now I will take a video and post back. Thanks again

 

Thanks for your response. Only things I have checked are the TPS and MAF. I put a used MAF today and behavior is the same. The jerky RPM behavior when I accelerate and on a slope have to give a lot of gas before it climbs. I will try to take a video and post back. I will check on the knock sensor as well.

 

Yes the car is not misfiring. I had 2 injectors changed last year and also changed out the injector harnesses. So I am not sure it is an injector issue. I had the battery disconnected for over a week since I was out of town. I just connected it back and put in a used MAF but it still has the 2 issues:

1. It seems to be starting in a higher gear i.e. if I start it on a slope (driveway) the RPM goes to about 2000 before the car moves. This may be the fail safe mode.

2. Once the car is in motion, the rpms keep jumping up and down (surge) and feels like the car is alternately getting gas and then throttled. I lost my MAF bracket when I was trying to change it. But I have made sure that the connector is snug. I need to see if I can buy a replacement bracket. But I doubt the surge is due to a bad connection at the MAF

 

Thanks for sharing your experience.. The car is not stalling when I am stopped. Only thing common with your issue is the jerkiness when I am driving the car. But I will check the grounding of the MAF. When I had checked it before it seemed to be ok

 

Attaching some videos

1. Going up the driveway:
RPM seems to shoot to around 2K before the car starts to move



2. Car in motion. jerky motions, RPMs fluctuating. I am not flooring the accelerator. Watch the tach needle fluctuate


3. TPS code 43 on ECU after the test


Any ideas?

Thx

 

It almost seems like you've got an air/fuel issue as well. RPM should not oscillate like that, even a multi-cylinder misfire would not cause an oscillation that noticeable (the peaks and valleys in your RPM variation are too far apart to occur within a single revolution of the camshaft). Might be worthwhile to throw a fuel pressure gauge on there and make sure the fuel pressure isn't dropping severely during those fluctuations. Which might require you to drive the car with the hood removed so you can see the gauge, but whatever, this is troubleshooting

Also, look into the tests here on http://www.nicoclub.com/FSM/Maxima/1994/ec.pdf

Pg EF&EC-67 - "hesitation under normal conditions"
Pg EF&EC-112 Error code #43 - TPS circuit check
Pg EF&EC-145 "tps component check"

 

Thanks for the pointers. For the fuel pressure check I will see how to get that done. I dont have a fuel pressure gauge.

On the other checks,
Pg-67 I previously performed the O2 sensor check and it was fine. I will look at the other checks
Pg 112 - I need to perform those
Pg 145 - I had performed the resistance check but it only goes to 7K ohms

 

On pg EF&EC-146 it has a procedure for adjusting the TPS. If it's not adjusted just right, the ECU and TCU can mis-interpret what the sensor is telling them (ie at-idle when it really isn't, etc).

 

Hi Caped Cadaver et al,

Wanted to post back as I think I finally found the problem. Took me many frustrating weekends to isolate the problem as I could not look at it during the week...and luckily I had another car to drive as a backup.

The root cause solution will probably help others as well.

First off I tightened the MAF sensor using a hose clamp. It was loose. I had lost the clip and courtesyparts said they can only sell the clip with a new MAF sensor for $400+ bucks.

Second I opened the TPS connector, it was very dirty. Cleaned it up good. Problem was lessened but did not go away.

Opened the ECU harness and checked harness continuity to TPS connector. Was good.

By luck, I noticed that the wire which sends the +5V reference voltage to the TPS had become stiff over the years and the TPS was intermittenly receiving the 5V reference signal or not receiving it when I moved the wire. It was probably getting pinched. I straightened the wire and using a tie I made sure it was secure and held in place.

I believe this was the ROOT CAUSE of the problem.

The car seems to be driving fine now.....Thanks again for your help

 

alu2007,
I'm having the same problems as your videos. Was this a intermittent problem or was it every time you drove the car? My issue is intermittent. Haven't had a chance to check the resistance. I had a dirty TPS connector as well.

Where was the 5V wire that was getting pinched? Don't suppose you have a picture of that?

 

Mine was intermittent at first but then it would happen all the time. It would be a good idea to clean the TPS connector to get rid of all the green oxidization. I used electrical contact cleaner for it.

Have you checked your ECU codes? I was getting a TPS code. Maybe thats a place to start troubleshooting

The 5V wire was getting pinched at the TPS connector itelf. Kinda like a headphone wire that gets pinched and you dont hear sound in one ear. I just had to straighten it out a little and hold it in place using a plastic tie so it did not move much. I can post a picture of the connector later if you need one

 

I did spray that on there. I'll take a wire brush to it this weekend.

I don't think any of the wires are being pinched at the connector. Are you talking about on the potentionmeter? Gray harness or the black one?

 

I am having a similar issue. I have had 2 injectors replaced, all new belts, almost all gaskets replaced, Cts, and gauge temp sensors replaced, and a new radiator cap. I am hoping mine is a simple fix, and the forum has been invaluable thus far with quite a few helping me work through getting my max back up to snuff.

What my max is doing is at acceleration at take off it seems to have plenty of power. I lived in a semi-mountainous region when just going down the road, If i go into passing gear it shifts down, but no really noticeable boost in power with speed bump about the same as not allowing it go down into passing. When I am just driving and start to go up a hill, it starts dropping speed. if I press down more, it may pick up a little speed, but not a lot and may still drop speed. I am just perplexed by this. It should be noted that my exhaust system needs replacing, and I will do that into the near future. Could that be the source of my issues?

 

No it is not the potentiometer. It is the other harness connector.

 

In my case, the ECU was spitting out the TPS code - 43. If you are not seeing an ECU code, then it could be a different issue. Regardless, it would be good to clean the TPS contacts and the throttle body. Looks like you already cleaned the contacts.

 

Ok Update: My car went into fail safe mode today, and it has done it before, I just didn't recognize it as that until today, thanks to the forum. It would rev past 2500 when I put it in park, but would not shift out of third on take off, and would not rev above 2500 while in D. I did what I have to in the past, put the car in park, turned it off, and turned it back on and it worked correctly. The car has done this a few times. Where are the plugs for the maf, and the tps? It just happens every now, and then so I am hoping it is a corroded plug that is causing an occasional bad connection. Are there other things that put them in safe mode? I need to learn how to get codes.

 

The MAF is close to your air filter. See the post by maximajquery in this thread. It has a picture of the MAF connector. To my knowledge, a MAF issue is one of the reasons that can put it in the mode you describe.

I found the Chilton's manual to be a very good resource for troubleshooting. It has the procedure to get ECU codes. Just try googling for the chiltons manual for your car model/year. The manual is pretty cheap online. You should also be able to find the TPS info/illustration there.

NOTE: I think the Nissan Factory Service Manual (FSM) is also good but the Chilton's helped me more.

 

Distributer

 

what seems to be might be a bad TCU (transmission control module) . I bought my maxima with a bad TCU (found out after I bought it) the car was stuck in 3rd gear, sluggish but would speed up to 65 at about 3000 rpm (3rd gear only). sometimes it would out of nowhere take off and shift like a bat out of hell so I put bad transmission out the window and started searching electrical. everything checked out fine except one transmission solenoid. shopped around and asked how much for them to swap out the solenoids but no one would do it (liability reasons) even if I told them that if it doesn't work it's fine I'll still pay . found one guy who did it (trans shop) changed me 250 but when I picked up the car it was the same so he was Kool and took off 50$ . I was already with the mind set of replacing the transmission solenoida and TCU so was no problem . that Sunday I went to the junkyard and bought a TCU for the car and installed it in the parking lot. and wouldn't you know damn thing was shifting fine no more limp home mode and till this day it's fine . the TCU is located above the ECU