Faulty TPS on 1990 3.9 RRC?

I've posted this separately from my 'Ongoing Woes' thread as I'm being a bit more positive here and to narrow it to just TPS thoughts. (Hope that's OK.

The symptoms were that the engine died (and refused to restart for a long time) as I accelerated having slowed for a roundabout.

I noticed last night without giving it any significance that when I was prodding around the replaced plenum-to-inlet manifold pipe to show the recovery man what I had done, that the idle speed changed (briefly).

I've been fiddling some more today and found that I could reproduce the revs drop and then pickup and, best of all, actually make it stall by flicking the throttle from the idle stop to just off idle. If I disconnect the Throttle Position Sensor I cannot make the engine stall using the same process.

Engine (seems) to run happily without the TPS connected.

AIUI the TPS informs the ECU of fast movement of the throttle which results in more fuel being supplied to provide greater acceleration.

What do you think?

Could a damaged track in the TPS cause these symptoms?

What about the period when I did start the engine but it raced at between 2750 and 3000 revs with no throttle input?

I can pilfer the TPS from my 3.5 RRC. I'm used to stuffing needles into wires to set the TPS position on my bike and have a Fluke meter which will display mV.

TIA

Richard

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Richard
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Ah Mr Richard sir......

Still having problems with the RRC i see. Thought you were going to get rid of it and get a Izusu Trooper!!. Re the poss faulty TPS, i may have one doing nothing, will check the shed tomorrow. See you in 2 weeks??.

Dom

Reply to
Dom J

Further to the above; can anyone tell me what the correct voltage to set the TPS is? My CD manual doesn't have a value for the 3.9 engine. I do have the paper manual which gives a voltage for the 3.5.

TIA

Richard

Reply to
Richard

Volts should read .33 to .35 volts

Reply to
Richard

Hmm. so 250mV ain't too good? The 3.5 book says 290mV +/- 20mV IIRC

Richard

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Richard

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