I used this thread to adjust my TPS last night as a recent conzult showed it was slightly out of the ideal range.

http://www.300zx.co.uk/forums/showthread.php?t=83683&highlight=TPS

I do not have a conzult so tried to make the adjustment using a voltmeter also described in the thread. When I connected the voltmeter to the neg battery terminal and the middle pin of the connector I got a 12+V signal. I could not find a voltage that showed anything similar to the 0.45 – 0.5 V range using all the settings on the volt meter and all the combination of pins in the connector and neg terminal.

 

I tried a bit of guess work to adjust it by trying to get it in the middle. I followed the reset procedure and now I have a really high idle (just below 2k) but no other noticeable affects.

 

Can someone point me out how exactly to measure the current with a voltmeter? If not I will just adjust it until I get a satisfactory idle and wait until I get another conzult to adjust it to the correct parameters.

it is the middle pin...but just a thought is your meter calibrated...try metering a 5 volt line on your PC etc as a test...could be just the meter is reading wrong

tried the middle pin. dont think it could be meter calibration as it is showing 12+ volts! it is also a digital meter so probably unable to slip like anolgue gauges.

 

As far as i remember, every time i have checked for a voltage most places on the car it reads out 12+V more or less (expect when it is going to ground and stuff like that) am i using the wrong setting on the meter? It is just the volt reading in 20's i think. I am a bit electronically incapable to tell the truth. Tried all the other settings on the meter to see if there was anything that resembled a 0.45 - 0.5 signal but the ones i found that changed when i moved the TPS werent in the above range.

 

this is the exact multimeter i have:

http://www.maplin.co.uk/Module.aspx?ModuleNo=44679&criteria=multimeter&doy=18m7

 

The mode i had it on which read 12+V was the 3rd round to the left of OFF. The probes where plugged in to the middle and right sockets. but like i said i tried every combination of setting and probe configuration i think.

I know this is NOT the way it should be done but I have done this on several occassions when I did not have access to my ConZult diagnostic kit (which makes adjusting the TPS a doddle! ;))

 

Have the car idling and disconnect the yellow connector off the idle control valve.

Slightly undo the two bolts securing the TPS and gently rotate the TPS until you hear the rpm's increasing.

You want to secure the TPS at the point just before the rpm's increase.

Reconnect the yellow connector.

Turn off the engine, disconnect the TPS connector and turn on the ignition for a few seconds (this will reset the ECU setting for the TPS).

Reconnect the TPS connector and you're done!

 

For what it's worth, 0.40~0.45V is not set in stone as being the ideal voltage. It is the range which is more important.

 

HTH

 

Dan

 

PS - your best bet is to hook it up to a ConZult and then set the TPS (and base idle while you're at it).

Thanks Dan. Not 100% sure what you mean about this bit:

........gently rotate the TPS until you hear the rpm's increasing. You want to secure the TPS at the point just before the rpm's increase.

that sounds a bit tricky!

 

Do i first turn it to the low rev point as a start point then rotate it until just before the revs increase? Is this correct.

 

1. Does it affect things that i have already set the TPS to an incorrect level? 2. Do i need to do the reset before i start because what i have done already or just when i have finished?

3. Does the car need to be warmed up?

do a search for "idle adjustment" mate. there is loads of info on here about this :)

there are plenty of threads on adjusting idle but there was nothing wrong with my idle before i started monkeying around with TPS and need to find out how to get my TPS back to normal without the aid of conzult and without touching the IACV.

Only way you could get 12v on the middle pin is with a bad earth to the TPS....

middle pin measured against batt neg terminal gave 12V. Did i use the right setting on the multimeter......?

Thanks Dan. Not 100% sure what you mean about this bit:

 

that sounds a bit tricky!

 

Do i first turn it to the low rev point as a start point then rotate it until just before the revs increase? Is this correct.

 

1. Does it affect things that i have already set the TPS to an incorrect level? 2. Do i need to do the reset before i start because what i have done already or just when i have finished?

3. Does the car need to be warmed up?

 

It's not as tricky as it sounds ... ;) But then nothing is if you know what you're doing LOL!

 

I would recommend you make a small mark where the tps is set at now and then start rotating. That way you can always return it to where it was originally. You don't turn the tps to the lowest point - just rotate it either way to see what happens to the rpm's. At some point you'll either hear the rpm's drop or rise and that's the point you want to be at.

 

In answer to your other questions:

1. Yes, it will have an effect on other settings but don't worry too much about that.

2. Just do the reset when you've finished. You may also reset the ECU after you are happy you've set the tps correctly. In the absence of a ConZult just disconnect the negative terminal on the battery for a couple of hours - that'll do the trick.

3. Yes, car needs to be at normal running temperature and if you've got an automatic put it in Neutral.

 

Hope the above clears a few things up - if in doubt give me a call and I can talk you through it (07044016586).

 

Good luck!

 

Dan

 

PS - just a thought, Mark Hanley (aka Topless on this forum) has a ConZult and could help you sort this, plus he's in London as well!

Yeah Mark used his conzult and saw my TPS was a bit out. He told me to wait until i get my O2 sensors done then we would have another look at it but i can be an inpatient sod when i get the afternoon off work and it is nice outside!!

 

i can mark where the TPS is now but that is not going to help me because the current position is giving me 2k revs at idle! I guess i should just turn it until i get respectable revs at idle and do the final adjustment with Mark and the Conzult. What is usual idle revs? about 900?

Yeah Mark used his conzult and saw my TPS was a bit out. He told me to wait until i get my O2 sensors done then we would have another look at it but i can be an inpatient sod when i get the afternoon off work and it is nice outside!!

 

i can mark where the TPS is now but that is not going to help me because the current position is giving me 2k revs at idle! I guess i should just turn it until i get respectable revs at idle and do the final adjustment with Mark and the Conzult. What is usual idle revs? about 900?

 

 

Adjusting your tps won't neccesarily affect your idle - that's held by the ECU IF your base idle isn't set correctly. And that's a whole different kettle of fish!

 

Suggested course of action:

 

1. Replace O2 sensors

2. Clean Idle Adjustment Control Valve

3. Reset TPS

4. Reset base idle

5. Re-check TPS setting

6. Reset ECU

 

Can't be any more help than that I'm afraid ... But I do know what it's like to be an impatient sod (story of my life!) :) LOL

 

I'd wait until Mark can get his hands on the car - with a ConZult attached it is so much easier to set the above correctly.

 

Good luck mate!

 

Dan

Voltmeter setting shouldn't afect it - make sure its set to Volts though or you'll blow the meter up. If its reading 12v then there is more than likely a problem with the earth to the TPS. What is the voltage reading between the white and black wires? (black wire is the earth for the TPS)

i have deffinetly done something to the idle since fiddling with the TPS last night. I cant really drive about with a 2k idle espeacilly in london where i am idling at traffic lights most of the time. Besides, it is looking nice out today so i will give it a go tonight to try and get the idle back to normal with the position of the TPS. will let you know how it goes.

Dude bring it back over and we will do the tps, but those O2 sensors need installing!

tonight? i can live with it for a bit if it is a trouble.

 

O2 sensors going in Friday morning......hopefully i will have it back for the weekend. The guy at the garage said it should take long if they are reasonably accessable......I said, "yeah, it should be fine". GOOD LUCK BOYS!

Well I am probably going to be back in for 8ish, pop round after that if you want?

cheers mate. I will give you a bell. I will try not to keep you too long. I always enjoy the blast back from your place through barnes!

Sorry for not letting you know last night Mark but got this sorted.

 

realised the plug you guys where talking about to test the voltage is the GREY one going to the bottom of the TPS not the BLACK one going straight into the TPS.

 

Adjusted it to cock-on 0.45V and i now have a more civilised idle of just over 1k revs.

 

When i got it to that i just bolted it down but i was wondering which gives the higher & lower revs is it more voltage for higher revs or more voltage for lower revs?? ie is 0.45V giving me high idle and if i went to 0.5V i would get a slightly lower idle. What would this cause (apart from slightly better mpg)?

 

Will still bring the car round to you Mark once the O2 sensors are done for another conzult if that is cool with you?

I am not sure i reset it properly.

 

Turn off the engine, disconnect the TPS connector and turn on the ignition for a few seconds (this will reset the ECU setting for the TPS).

Reconnect the TPS connector and you're done!

 

which of the TPS connectors do diconnect? the black one directly connected to the TPS or the grey one that leads to the bottom of the TPS?

 

Do i need to remove the yellow idle connector when i do this reset (in the words of Shalamar) "Second Time Around"?

I am not sure i reset it properly.

 

 

 

which of the TPS connectors do diconnect? the black one directly connected to the TPS or the grey one that leads to the bottom of the TPS?

 

Do i need to remove the yellow idle connector when i do this reset (in the words of Shalamar) "Second Time Around"?

 

No, leave yellow connector connected and disconnect the big black connector which goes directly into the TPS.

 

Dan