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Discussion Starter #1 (Edited)
Tried 2 different tps switches. Both check out fine .98v idle then smooth to 4.86v WOT& other .94v idle 4.54v WOT.
My anderson PMS shows both smooth and working fine no codes KOEO.
Once I fire it up display shows erratic throttle response like it's not opening enough, where as ignition on, not running smooth as butter, so obviously getting wrong info to ecu, hence crap running.
Changed first tps, was fine. Now day later same issue with either.
Salt n peppers clean. Added pics to show those unfamiliar with the old PMS. Again sweeps progressively idle to wot ignition on, running almost stays at idle then shows much lower reading than it should with press on gas pedal.
Any ideas?

Update; tried 3rd tps switch, all good for say 4 mins...idled revved up...then started reading slow and engine was a a slug, missing. Bad connection/wire?
I will run a KOER when I can get some help.
 

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what i am supposed to see from those pics?

get a graphing meter, and perform the sweep, so we can see there are no glitches

if the tps checks out with a meter........the tps is fine, why would you install a new one?
 

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Discussion Starter #3
Hi Indy, I have spare parts as I'm in the UK and they are not as available here so keep them to hand, saves the wait.
The tps is good with ignition on, Check it on a DVM. The Anderson PMS display shows the same but as Idle percentages then wot, as well as other parameters. I fire the engine up and the tps is almost unresponsive on the screen and runs rough as in no throttle response (bad tps)
I could add video to show, but engine running gives symptoms of bad tps as in unresponsive sweep and adding throttle stays at idle, may jump to up but slow and only idle volts at say 1500rpm foot on gas.
Replace tps all seems good for 1 or few minutes then breaks down again.
So by changing tps twice I feel that's not the issue.
No other sensor issues, and only engine running.
I don't know what a graphing meter is, I'll look into that.
Again sweeps smooth no glitches on dvm and display with ignition on engine off. Gets funky with engine on either straight away, or 1-5 minutes later hence could it be a short on one of the 3 wires.
Any ball park ideas.
 

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backprobe the the three wires off the tps with engine running at the tps

if good then backprobe at the ecm
 

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Discussion Starter #6
Pulled the ecu, 2 or the 3 capacitors ####ed. Getting all 3 replaced and board checked out.
Only when I wiggled them and the 1 leg from both came away. Hope this puts all my gremlins to bed.
 

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It might

But i dont see that part of the 5v regulator
 

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Discussion Starter #8
Get the ecu back tomorrow. Had 3 bad capacitors and burnt trace on one.
Let's see how it goes, will update here of course.
 

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Discussion Starter #9
You was right Indy. Repaired ecu put in...Same as before, ok on PMS screen and dvm on tps KOEO. Start car and no throttle response on PMS or dvm on tps...hardly moves. Back probed tps same, hardly moving. I will back probe ecm connection next. KOEO and running when I get time.
So if it's bad at tps only with engine running any more ideas?
Run out of daylight and don't have a garage.
ECM disconnected, the 60 pin 3 wires to tps ( 46-47-26) all check out with the random "beep" test for connection.
No other sensor issues, and the sig rtn to all sensors and ecm do the same.
Engine running is what causes the issue.
Appreciate your help.
 

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forget the pms, its really junk

use a dvom and measure

you need to verify the 5v ref

is the ecm making it?

is it being shorted by a sensor?

all with a dvom

these repair places do NOT actually test the ecm, its well documented

another poster went through the same issue, the 5v reg on the board was shot
 

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Discussion Starter #11
Got 4.99v on ref wire KOEO. On TPS.
Not checked in KOER ( will try tomorrow)
Back probed TPS KOER 0.98, few blips of throttle no higher than 1.46v.
Swooped out another TPS sensor, same result.
Goes lame once engine started. All readings good once shut off and KOEO?
Thanks for the response.
 

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does not sound like you installed the tps correctly

it doesn't just bolt on

the flange needs to be on the correct side
 

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Discussion Starter #13
I'll double check in the morning, but don't account for the same issues as the original one that just started acting up after running fine.
 

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you can test the tps, off of the TB

just connect it electrically and turn the wiper by hand while looking at the meter
 

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Discussion Starter #15
you can test the tps, off of the TB

just connect it electrically and turn the wiper by hand while looking at the meter
Sorry for the delay, had family business.
I did the above and my results are the same. All good ignition on, fire it up and hardly any response say.98 to 1.4v and not smooth at all.
Tried it while cranking, coil lead off and on ( fuel pump off on a toggle A1000) and it's fine-normal. So it's something when its actually running? Fuel pump running doesn't effect it.
The 5 volt ref (4.99 I get) is stable KOEO & KOER. only codes were emission related. Although today the code reader won't work. Sig rtn shows 0.5ohms between sensors, test port, and from sensors to ecm. KOEO.
So basically KOEO all good, including cranking. KOER, 5v ref ok but tps then struggles to send out volts, idle ok but no real response from pedal or manually moving throttle, ecu gets same results at its end. Sig rtns check out good for ground.
1/ Cranking means plugs sparking, tfi sending signal, pip etc; TPS responds fine...so apart from turning pump on (which as I said don't effect signal) what else can be happening to upset the tps signal leaving AT the tps from the green wire.

Rather confused!!!
I've found a3rd tps I have to try.
 

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Any ohm tests done, i will ignore and so should you, does not prove anything

Are you saying backprobing at the ecm connector tps signal is fine engine off, but no good on?

You are missing something with your testing, how the leads are setup is of utmost importance
 

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Discussion Starter #17
Yes that seems the problem, the tps signal is fine and smooth engine off, ignition on, cranking with coil lead on and off.
Engine running it struggles to leave idle voltage from both the tps and going into ecm.
My buddy is an electrician and is coming to help Saturday. He is better qualified to test stuff than me.
Running is not affecting 5volt ref, sig rtn checks out as grounded, just the green signal that leaves the tps.
Push throttle and wants to stay at idle volts or rise very little, hence rpms raise but ecm not seeing this.
It's like something interfering with this wire when running.
I know ecm supplies ground and 5v ref both seem stable KOER
It's the green return, and this just sends back voltage signal it's supplied with depending on position (obviously) and that signal only comes from the tps.
Sorry just thinking out loud!
Thanks Indy.
 

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again

are you checking the signal at the ECM CONNECTOR?
 

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Discussion Starter #19
Hi Indy, will do this Sunday with my buddy as I know he is 100% at this stuff.
Will confirm this ASAP, but no garage and working long hours, burst pipe and a funeral...not enough hours in the days at the mo. This will be first thing I do.
As always many thanks for taking time to reply.


More thinking aloud for who may read my ramblings;
I know the Anderson PMS is not everyone's favourite but it does show me what the ecu is seeing from my limited understanding.
The factory 60 pin goes into the PMS loom which in turn plugs into the factory ecm and branches into the display screen.
So my thinking was the display was confirming that info regarding the tps as it has to pass through the factory loom, PMS loom and ecm.
Also gives error codes including tps which it does not.
I could take the PMS off just to test tps but would run horrid, but may do to rule it out.
Pin 46 pins out all the way through to factory 60 pin, and the Anderson 60 pin and multi plugs in the Anderson ecm 0.5ohm.

I have bought a InterACQ data logger from a corral member (in transit to uk via container) so I can tune more indepth log and see more real time what's going on. especially on a pass....if I ever sort this tps out:crying2:
 

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I see no where in your previous pics of this pms

tps voltage???
 
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