Jump to content
SAU Community

Recommended Posts

I have a stock series 2 manual and when i got it, it was the smoothest car ive ever driven. I took it to my mechanic shop who is a well known dyno shop in melbourne. After getting it back its not smooth on and off the throttle, its got a little jerk. more noticeable when going realy slow but never the less noticable all the time. Its starting to give me the shits. I took it back to my mechanic and he said that theres nothing wrong with it, but i know what it was like before. so im stuck with it. Apparently the only thing they adjusted was the tps (throttle position switch). Does anyone know much about this switch and if it can be adjusted without hooking it up to a computer and where it is located?

Help anyone

Thanks

Stu

Link to comment
https://www.sau.com.au/forums/topic/275314-stagea-jerky-on-and-off-throttle/
Share on other sites

i know exactly what you mean. i accidently did it once when i was working on my old 32. it feels like the accelerator is lagging, and then all of a sudden it kicks in. and yes, it is related to the TPS. i cant remember which way it is but its if the TPS's closed voltage is a bit too high or too low it will cause this.

the tps is on your throttle body just before the inlet plenum. it needs to be set to the correct voltage when the throttle is closed, 0.3-0.5v. if your any good with a multimeter you can fix it up yourself, otherwise i'd take it back and tell them to get it sorted.

i know exactly what you mean. i accidently did it once when i was working on my old 32. it feels like the accelerator is lagging, and then all of a sudden it kicks in. and yes, it is related to the TPS. i cant remember which way it is but its if the TPS's closed voltage is a bit too high or too low it will cause this.

the tps is on your throttle body just before the inlet plenum. it needs to be set to the correct voltage when the throttle is closed, 0.3-0.5v. if your any good with a multimeter you can fix it up yourself, otherwise i'd take it back and tell them to get it sorted.

Thank you very much, it sounds as though your on the money. Another question is how do u adjust it? is there some sort of screw to adjust the voltage? What does it look like? the only thing i can see on the throttle body is a little black solonoid type thingy with about 6 wires coming out of it. Would that be it?

Thanks again

stu

Edited by sturb25

best i can do for you at the moment, is this pic. the black part circled in red is the TPS. the yellow circle is one of two bolts you loosen to be able to adjust the TPS, the other bolt is at the bottom of the TPS, you'll have to remove the covers to see it. once these are loosened, you don't have to remove them, just loosen. you turn it clockwise/anti-clockwise to adjust the set voltage.

you need a multimeter, one probe goes to ground/-ve, and the other goes to the TPS variable output (without rooting though wiring diagrams to find it, or probing for it, i cant tell you exactly which one it is) either on the TPS itself or the TPS signal input on the ecu plug. at the TPS itself should be the easiest to probe. then just turn the TPS until you get the correct voltage. then do the bolts back up, and recheck the voltage is right and nothing has moved while tightening it up. also take note that you have to set the voltage with the throttle closed.

another way to do it without a multimeter is to hook it up to a laptop and use a consult interface and monitor the voltage through that while you set it.

i suppose if you don't want to stuff around with all this you could just loosen the bolts, slightly move the TPS in one direction, tighten it back up and go for a drive and see how it feels, if its worse turn it the other way. its not ideal and you would still want to get it checked properly but it may help make it more drivable until then.

post-34711-1245321788_thumb.jpg

Edited by QWK32
best i can do for you at the moment, is this pic. the black part circled in red is the TPS. the yellow circle is one of two bolts you loosen to be able to adjust the TPS, the other bolt is at the bottom of the TPS, you'll have to remove the covers to see it. once these are loosened, you don't have to remove them, just loosen. you turn it clockwise/anti-clockwise to adjust the set voltage.

you need a multimeter, one probe goes to ground/-ve, and the other goes to the TPS variable output (without rooting though wiring diagrams to find it, or probing for it, i cant tell you exactly which one it is) either on the TPS itself or the TPS signal input on the ecu plug. at the TPS itself should be the easiest to probe. then just turn the TPS until you get the correct voltage. then do the bolts back up, and recheck the voltage is right and nothing has moved while tightening it up. also take note that you have to set the voltage with the throttle closed.

another way to do it without a multimeter is to hook it up to a laptop and use a consult interface and monitor the voltage through that while you set it.

i suppose if you don't want to stuff around with all this you could just loosen the bolts, slightly move the TPS in one direction, tighten it back up and go for a drive and see how it feels, if its worse turn it the other way. its not ideal and you would still want to get it checked properly but it may help make it more drivable until then.

post-34711-1245321788_thumb.jpg

Thanks again. will let you know if i have any dramas

my autech does this too...

if u put the foot in to like half way in a high gear... like 4th at 60ks... and pull it back to a 1/4 of throttle it jolts like 2 or 3 times... if u rip the foot off it stops instantly... would this be the same prob?

why would the voltage change? just ware and tare?

my autech does this too...

if u put the foot in to like half way in a high gear... like 4th at 60ks... and pull it back to a 1/4 of throttle it jolts like 2 or 3 times... if u rip the foot off it stops instantly... would this be the same prob?

why would the voltage change? just ware and tare?

sounds as though youve got a different problem, mines like a tiny jerk and it only does it when your on and off throttle all the time. hardly noticable but more noticable when your driving at 2-5km/h realy slow.

Hope that helps, but probably not!

best i can do for you at the moment, is this pic. the black part circled in red is the TPS. the yellow circle is one of two bolts you loosen to be able to adjust the TPS, the other bolt is at the bottom of the TPS, you'll have to remove the covers to see it. once these are loosened, you don't have to remove them, just loosen. you turn it clockwise/anti-clockwise to adjust the set voltage.

you need a multimeter, one probe goes to ground/-ve, and the other goes to the TPS variable output (without rooting though wiring diagrams to find it, or probing for it, i cant tell you exactly which one it is) either on the TPS itself or the TPS signal input on the ecu plug. at the TPS itself should be the easiest to probe. then just turn the TPS until you get the correct voltage. then do the bolts back up, and recheck the voltage is right and nothing has moved while tightening it up. also take note that you have to set the voltage with the throttle closed.

another way to do it without a multimeter is to hook it up to a laptop and use a consult interface and monitor the voltage through that while you set it.

i suppose if you don't want to stuff around with all this you could just loosen the bolts, slightly move the TPS in one direction, tighten it back up and go for a drive and see how it feels, if its worse turn it the other way. its not ideal and you would still want to get it checked properly but it may help make it more drivable until then.

post-34711-1245321788_thumb.jpg

This is probably going to sound realy dumb but i want to get it right. when adjustinng the TPS u said to adjust it with the throttle fully closed. does this have to be done with the car running or ignition on. sorry it sounds pretty dumb but i dont want to stuff it up.

Thanks

Stuart

engine doesn't have to be running but ignition has to be on, so the put the key in the ON position.

My TPS was reading 5.1 volts so i changed it to 3volts. tightened it up and rechecked. it read 2.9volts, went for a drive and it felt better but still not 100% so i tried 3.5volts. it seems to of improved quite substantialy but its rasied my idle to around 1500rpm. Is this normal? I adjusted my idle screw on the throttle body which lowered it to normal rate. Should i have adjusted that?

Stuart

do you mind PMing me where you took it? i am thinking i might take mine somewhere to get adjusted but i need to know where not too go if that makes sense, not to pay out the workshop, but just i dont have heaps of money to waste paying to get jobs redone when they should be done right the first time.

My TPS was reading 5.1 volts so i changed it to 3volts. tightened it up and rechecked. it read 2.9volts, went for a drive and it felt better but still not 100% so i tried 3.5volts. it seems to of improved quite substantialy but its rasied my idle to around 1500rpm. Is this normal? I adjusted my idle screw on the throttle body which lowered it to normal rate. Should i have adjusted that?

Stuart

no, i think you misread, it should be between 0.3 to 0.5v, not 3.5v. thats why you have an increased idle, because the TPS voltage is way to high. the TPS output scale is from 0-5v, setting it to 3.5v is like telling the ecu you have your foot 3/4 the way on the throttle, hense high idle.

Edited by QWK32

From the R34 Service manual;

TPS voltage (ignition switch on, engine not running)

accelerator pedal released approx 0.5Volts

accelerator pedal fully depressed approx 4.2Volts

TPS voltage (engine running at approx 2000 RPM)

approx 0.6-0.7 volts

Its best to adjust the TPS when connected to Nissan Consult. You want the idle position to be below the point where the 'idle closed' switch is activated. You might get this right just by setting via voltages, but you might not

Had same issue with my R31 a few years back, drove to Bundalong and back to Melb on one tank, best fuel economy i ever had, although it did shit me each time i lifted of the pedal at 100kmh.

Had to feather the pedal for a less annoying drive.

The old tps died a day or two before i left, so popped down the wreckers got another did a quick adjustment which was

not spot on, hence the annoying drive.

When i got back first thing did was start fixing, I just adjusted by feel / listening to the idle without the multimeter.

I found the adjustment is very sensitive, 1mm and its out.

Even when re-tightening the bolt you can chuck it out, so hold the tps firm when tightening the bolts.

From memory I rotated the the tps anti-clockwise to its full adjustment, then slowly rotated clockwise until it the rough idle disappeared and became smooth but a was a bit high at 900-950rpm.

Re-checked the timing and base idle (which was out 3deg retarded prior to this) and all was good back down at the base 700-750rpm, geez it felt damn good to drive after.

Maybe 60mins of work including test drives.

no, i think you misread, it should be between 0.3 to 0.5v, not 3.5v. thats why you have an increased idle, because the TPS voltage is way to high. the TPS output scale is from 0-5v, setting it to 3.5v is like telling the ecu you have your foot 3/4 the way on the throttle, hense high idle.

Sorry i stuffed up my decimal points. i meant 0.35volts and its rasing the idle and it was set to start with at 0.51volts

Edited by sturb25

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


  • Similar Content

  • Latest Posts

    • Hi, is the HKS  Tower Bar still available ? negotiable ? 🤔
    • From there, it is really just test and assemble. Plug the adapter cables from the unit into the back of the screen, then the other side to the car harness. Don't forget all the other plugs too! Run the cables behind the unit and screw it back into place (4 screws) and you should now have 3 cables to run from the top screen to the android unit. I ran them along the DS of the other AV units in the gap between their backets and the console, and used some corrugated tubing on the sharp edges of the bracket so the wires were safe. Plug the centre console and lower screen in temporarily and turn the car to ACC, the AV should fire up as normal. Hold the back button for 3 sec and Android should appear on the top screen. You need to set the input to Aux for audio (more on that later). I put the unit under the AC duct in the centre console, with the wifi antenna on top of the AC duct near the shifter, the bluetooth antenna on the AC duct under the centre console The GPS unit on top of the DS to AC duct; they all seem to work OK there are are out of the way. Neat cable routing is a pain. For the drive recorder I mounted it near the rear view mirror and run the cable in the headlining, across the a pillar and then down the inside of the a pillar seal to the DS lower dash. From there it goes across and to one USB input for the unit. The second USB input is attached to the ECUtec OBD dongle and the 3rd goes to the USB bulkhead connected I added in the centre console. This is how the centre console looks "tidied" up Note I didn't install the provided speaker, didn't use the 2.5mm IPod in line or the piggyback loom for the Ipod or change any DIP switches; they seem to only be required if you need to use the Ipod input rather than the AUX input. That's it, install done, I'll follow up with a separate post on how the unit works, but in summary it retains all factory functions and inputs (so I still use my phone to the car for calls), reverse still works like factory etc.
    • Place the new daughterboard in the case and mount it using the 3 small black rivets provided, and reconnect the 3 factory ribbon cables to the new board Then, use the 3 piggyback cables from the daughterboard into the factory board on top (there are stand offs in the case to keep them apart. and remember to reconnect the antenna and rear cover fan wires. 1 screw to hold the motherboard in place. Before closing the case, make a hole in the sticker covering a hole in the case and run the cable for the android unit into the plug there. The video forgot this step, so did I, so will you probably. Then redo the 4 screws on back, 2 each top and bottom, 3 each side and put the 2 brackets back on.....all ready to go and not that tricky really.      
    • Onto the android unit. You need to remove the top screen because there is a daughterboard to put inside the case. Each side vent pops out from clips; start at the bottom and carefully remove upwards (use a trim remover tool to avoid breaking anything). Then the lower screen and controls come out, 4 screws, a couple of clips (including 3 flimsy ones at the top) and 3 plugs on the rear. Then the upper screen, 4 screws and a bunch of plugs and she is out. From there, remove the mounting brackets (2 screws each), 4 screws on the rear, 2 screws top and bottom and 3 screws holding in the small plates on each side. When you remove the back cover (tight fit), watch out for the power cable for the fan, I removed it so I could put the back aside. The mainboard is held in by 1 screw in the middle, 1 aerial at the top and 3 ribbon cables. If you've ever done any laptop stuff the ribbon cables are OK to work with, just pop up the retainer and they slide out. If you are not familiar just grab a 12 year old from an iphone factory, they will know how it works The case should now look like this:
    • Switching the console was tricky. First there were 6 screws to remove, and also the little adapter loom and its screws had to come out. Also don't forget to remove the 2 screws holding the central locking receiver. Then there are 4 clips on either side....these were very tight in this case and needed careful persuading with a long flat screw driver....some force required but not enough to break them...this was probably the fiddliest part of the whole job. In my case I needed both the wiring loom and the central locking receiver module to swap across to the new one. That was it for the console, so "assembly is the reverse of disassembly"
×
×
  • Create New...