TPS wiring (1 Viewer)

[zimboy83]

Hello folks - had a question on the wiring for the throttle position sensor (tps). I am going through trouble shooting the cruiser not being able to rev above 2200 rpm, and when I remove/unclip the tps she revs just fine, so I'm pretty sure that it is something to do with the tps (read quite a few good posts on troubleshooting from the forum - I'm at the 'is it the wiring' stage). Wiring all looks fine (I just finished doing the head gasket and inspected the wire harness pretty well before putting it back). The one thing I did do is replace the female clip on the tps - two wires were frayed. I'm worried that I maybe messed up re-wiring hence the malfunction. Is anyone able to verify based on their own working tps, whether the colored wires are in order? Please see a picture of mine below - cruiser is 1997 US model. Many thanks in advance!!

 

[bpenn1980]

Hey @zimboy83

When you say wont rev past 2200rpm, does it get to 2200rpm and then fall to 1400rpm?

I'm diagnosing (/firing the parts cannon at) this issue. TPS is on my initial list of things to test. Will probably get to it tomorrow.

Hope you managed to solve your issue

 

[jonheld]

Those wires look reversed to me. Pin 1 should be on the right in that picture.

 

[zimboy83]

Hey @bpenn1980 - so after tracing all my wires from the wire harness I noticed about 4 that were either shorting or visibly in bad shape.
There is also a test in the FSM to check at the ECU for electrical shorts, and I kept getting a bad reading.
I ended up just splurging and just getting a new wire harness because I was almost 1 month deep into diagnosis lol.
New wire hire harness fixed my issue and car is revving as it should, no check engine light etc!
If you need any more info on the above just tag me here and I can see what I can do!
@jonheld I guess we will never know if my shoddy wiring was really the culprit and I could have saved myself a pretty penny on the wire harness

 

[zimboy83]

@bpenn1980 - sorry I realize I didn't answer your actual question. Yes it would get to 2200 and then drop to a lower Rev count around 1400. Culprit likely being a short somewhere in the engine harness.

 

[bpenn1980]

@bpenn1980 - sorry I realize I didn't answer your actual question. Yes it would get to 2200 and then drop to a lower Rev count around 1400. Culprit likely being a short somewhere in the engine harness.

I think you were on the right path with the TPS fwiw. That specific pattern of cycling up to 2200rpm from 1400rpm seems to indicate TPS short. In my case I think it was water in the plug.

I'd like to find a new engine harness for my '94 so I can replace it when I do the head gasket eventually.