Jump to content

TPS problem? Help!


SpaceCadet
 Share

Recommended Posts

So my 95 pathfinder xe v6 was shifting funny and had a high rpm idle and also the CEL light came on. Code 43 TPS... Went and checked it out and found that the connector had come lose, so I plugged back it in. RPM immediately went down and there was no longer that lurch forward when I shifted from P to D. I thought "great! problem solved!" Think again.. I go to give it a spin around the block and wont go past 20mph and when I try to go faster it prevents me from doing so. Is this "limp mode"? If so how the hell do I get out of it?! What other problem could it be? :headwall:

I need to drive it around for work and I have class tonight!

Any help would be appreciated!

Link to comment
Share on other sites

Unplug the battery for a bit and reinstall. Make sure the connections are good. Let the ecu relearn.

Thanks,

I read the FSM on fail safe reset and followed the procedure. Still does it. Also the power switch light doesn't blink anymore...which it used to but it would blink all clear before I plugged the TPS back in. Is it supposed to do that?

 

I try the battery trick now and see what happens.

Link to comment
Share on other sites

In the service manual ec-12 for the 95 it describes the tps and gives a pinout of the sensor so you can test, check for supply voltage, and signal voltage, I usually back probe the connector with a paper clip. Any more back story on the issue or what may have caused it, daily driver vehicle, sitting a long time, recent wheeling/mudding trip any recent work performed on the vehicle. The more info the better we can help. also looks like cam signal sensor can put it into a limp mode

  • Like 1
Link to comment
Share on other sites

The light not flashing is good--it means the TCU doesn't think there's a problem that it needs to tell you about. This does not mean there's no problem, though, it just means that problem is not something the TCU knows about. The computers on these things are not especially perceptive. +1 on what Snowboard said about testing the sensor.

 

 

If there's a limp mode that limits the truck to 20 MPH, this is the first I've heard of it. The ECU limp mode I'm familiar with limits the engine to around 3k RPM.

 

Is the transmission shifting? What are the revs at when it hits this apparent limiter? I'm wondering if an ECU limp mode plus a transmission that doesn't know to shift out of first gear might be causing your issue.

Link to comment
Share on other sites

In the service manual ec-12 for the 95 it describes the tps and gives a pinout of the sensor so you can test, check for supply voltage, and signal voltage, I usually back probe the connector with a paper clip. Any more back story on the issue or what may have caused it, daily driver vehicle, sitting a long time, recent wheeling/mudding trip any recent work performed on the vehicle. The more info the better we can help. also looks like cam signal sensor can put it into a limp mode

Just tested TPS, power and ground and its all good and within range. I just got the vehicle with the check engine light on. guy told me it as the knock sensor...no knock sensor code when I checked it... from what I can see the previous owner spliced in a new connector for the TPS. So I don't really know its history other than its from Florida.

Link to comment
Share on other sites

The light not flashing is good--it means the TCU doesn't think there's a problem that it needs to tell you about. This does not mean there's no problem, though, it just means that problem is not something the TCU knows about. The computers on these things are not especially perceptive. +1 on what Snowboard said about testing the sensor.

 

 

If there's a limp mode that limits the truck to 20 MPH, this is the first I've heard of it. The ECU limp mode I'm familiar with limits the engine to around 3k RPM.

 

Is the transmission shifting? What are the revs at when it hits this apparent limiter? I'm wondering if an ECU limp mode plus a transmission that doesn't know to shift out of first gear might be causing your issue.

Tach doesn't work so I don't know what rpms it reads but from listening to it, it doesn't go above 2k rpm. It will shift to 2nd but that's if I feather the pedal just so.

Link to comment
Share on other sites

Could it be the MAF sensor? it looks like the ground was repaired/replaced before. i cleaned it a couple of weeks ago but this is before i discovered the TPS was unplugged. Does a bad MAF throw a code?

Link to comment
Share on other sites

One thing, when i tested the TPS read .63Vdc closed, 4.27Vdc open. it should be .4v DC closed, 3.5-4 v DC open. Could that affect it?

That should be close enough.

Link to comment
Share on other sites

Spliced in? Doesn't sound right. It's plug and play

I think he means a new harness side connector was spliced in.

 

The lack of a tach reading could indicate an issue with the cam sensor but that should throw a code.

 

Have you checked fuel pressure yet?

Link to comment
Share on other sites

I think he means a new harness side connector was spliced in.

 

The lack of a tach reading could indicate an issue with the cam sensor but that should throw a code.

 

Have you checked fuel pressure yet?

Exactly, Thanks for making it understandable snowboard. I figured the lack of tach was just an instrument cluster issue...shouldn't an MAF show a code as well? I've read somewhere that sometimes it doesn't. Could that be the case for a cam sensor?

Haven't check fuel pressure. Would that change if the TPS went from unplugged to plugged in? Because don't forget, it drove ok before I plugged it in...not great but ok.

Link to comment
Share on other sites

I would start looking at the splice job. Is everything landed in the right place? No wires making contact with something it shouldn't, like bare spots on a neighboring wire.

Link to comment
Share on other sites

I took it to my mechanic this morning to take a look and see what he comes up with. I'll let you guys know what he says as soon as I find out. Thanks everyone for all the help! If your ever in Buffalo, beers are on me!

Link to comment
Share on other sites

So my mechanic still has it and I stopped in today and what he had to say is that his gut tells him its the MAF. He is doing pin point testing on all sensors to really see because he notices that the busted Tach responds to the motor not going above 20mph when it bogs and kicks so he wants to see if that's related. He's got 4 hours into it already and said hell make sure he doesn't go over $1000.00 :suicide:...

Link to comment
Share on other sites

A little update... Its still in the shop. My mechanic cannot figure it out yet.. He has checked everything! Upon doing some research myself and looking at the wiring diagrams and came across the revolution sensor and how it is connected to the TPS. I brought it up to him and he has not check that yet thinking it couldn't be the problem. I left him the diagram and he said he'll look into it today. I read on a forum somewhere of someone having a similar issue and it ended up being the rev sensor. does anyone have any incite on failed rev sensor symptoms? There is no code for rev sensor in diagnostics and in the FSM it shows that the rev sensor could effect it going into fail safe mode.

If this doesn't work I'm going to try switching out the ECM. Do you know where I could get a used ECM at is trusted?

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...