Car keeps climbing revs on idle

Hi guys, i went to start my car the other day after a month of hibernation and all it does is increase the revs. I've changed all vacuum pipes in may and it was fine so i doubt its anything to do with vac leaks. Could it be my tps? My car used to struggle keeping revs when launching etc because it would go up and down the revs all the time.

First time it started going from 1200rpm to about 2000rpm and down and now all it does is increase the revs as i turn the keys.

Any ideas on what it could be??

Throttle cable under bonnet or butterflies jammed open ?

nope they move perfectly fine ;x

im really lost on this one, i was thinking tps but how would the tps cause my revs to climb up so high without the throttle butterflies opening?

So at the moment when you start it, would the revs skyrocket if you didn't turn the car off? Its not going to be the tps. I think it has to be something with the trottle cable, butterflies or idle screw?

Its all i could think of top of my head both sets of butterflies or cable

Idel controll valve ? Would this cause it ?

I think idle control value would could cause an erratic rpm/ unsmooth idle or stalling. It depends how high rpm are we talking about? I'd say if it's now going above 2000rpm and beyond it might not be the value but it's a possibility based on the above.

idle control valve is highly likely, take it off & clean it with carb cleaner.
Even faulty dump valves can cause leak back on vacuum line but your symptoms sound spot on for ICV to be inspected first.
Also check temp sensor ok .
Useful thread on this linked below>
http://www.gtir-motorsport-club.com/t2701-high-idle-probs

since i got the car i had trouble with high idle and hunting revs etc.

Baisically i start the car, and all it does is increase the rpm. One time it shot right up to like 6.5rpm and i just turned it off, i dont want to try how high it will rev now but when started the revs shoot up.

Idle screw hasnt been played around with so i doubt is that, i need to check the back of my intake and see if theres any split idle control valve hoses or anything ;/

6.5rpm!! that's not good at all

yeah tell me, im 100% sure that its not the throttle bodies, i think that i have a big ass air leak somewhere in the idle control valve.

I even remember doing some track days and lets say i was on a start line trying to stay on 4k rpm with my foot steady the car would hunt the revs from 3500-4000rpm up and down. It did that recently and then developed into the rising revs on idle, i dont really fancy testing out how far up the revs it will go this time tho

I might take the intake off soon but i really cannot be bothered in this weather haha

Mmm that is quite odd extremes, is it intermittent or do you always have some irregularity big or small with revs ?
Is PVC system all standard ?
FPR working correctly ?
throttle plates & all linkages need good visual check for issue ?
Being that severe it should be easier in theory find fault ...

Loosen the throttle cable a wee bit it might help.. No harm in trying

either the butterflies are jamming intermittently ion the bodies or the tps is boogered and giving random readings, an air leak will not cause revs to go that high

Butterflies are not jammed, i think it might be the tps. What will happen if i just unplug it?

Also could it be my temp sensor ? showing wrong temp and making the engine rev higher? I might have to try and see if the revs go skyhigh again or if they will stop at 4k or something.

MR B - My car always had idling issues but most of them were cured with new vacuum lines etc, ran fine for past 6 months but all of a sudden after a month of not being on it decided to do that ;/

I think fact need highliht is only way car going rev like that is if it getting air,
and a lot if going that high.
I have seen the air valves & leaking BOV signal lines cause idles @2800rpm in couple of odd cases.
Seen fuel pressure issues cause fluctuating idle.
Same with TPS, it can cause fluctuations by passing bad signals so revs can fluctuate or go bit high but not 6000rpm high.
I have worked on at least 2 Rs with throttle body issue, one with excessive bore & plate wear so idle was high & one with wear causing some sticking & high revs.
Due to your prolonged history with idle speed problems it is possible you got more than fault creating your some what unique high idle .
Quite curious on what it turns out to be.

TPS would surely just cause a terrible idle, for example when I wired my aftermarket ecu I wrongly wired the TPS and it was reading 100% open at idle. No excessively high idle, just filled the garage and house in smoke

gtir_woody wrote:TPS would surely just cause a terrible idle, for example when I wired my aftermarket ecu I wrongly wired the TPS and it was reading 100% open at idle. No excessively high idle, just filled the garage and house in smoke

Basically if they send alternating signal they do cause fluctuation in revs due to ecu tweaking fuel/ign but minimal, much same as fuel pressure issues such as FPR & iffy pump can cause idle revs fluctuate minimal amount due to varying fuel.
For serious revs it need serious amount of air & that throttle plates or air valves generally.

Sorry but i havent actually mentioned this, when my car was going up and down on the revs i reved it a little and it went up to 4k and then started going up by itself. This could of been the butterflies getting stuck but they are fine now. I might need to get in my car and see how far the revs will go up. it goes well past 2500rpm atm but i need to check properly and i shall report back

I just have to see but i cannot be bothered to go out in this shit weather haha

^yes I can imagine not best weather for doing jobs like that, sunshine makes things like this much more enjoyable.

I think your issue was/is probably 2 problems, due to being standing throttle plates sticky & previous fault with idle valves or something causing the initial high idle fluctuation.
Just need run through everything logically, plenty of info on testing & cleaning the various air valves, also plenty of info on test TPS function & making sure it setup spot on.

Yoooooooo! I finally found some time and decent weather to have a look at the R.

First thing first i went in and started it to see where the revs will stop. It reved up to around 3200rpm stayed on there for two seconds and then dropped back down to 2k  ???

I cleaned the MAF and now the car idles at 2k rpm but hesitates and revs between 1500-2k rpm up and down all the time? i tried to adjust the TPS and see what that does but it only made it worse by revving up etc etc. i even have videos to show but they are taking ages to upload. I can defo hear like a sucking noise as if it wants to stall from lack of air but it still revvs up?

Also when i rev up to 4k or something it will get stuck on these revs for a second or two and then drop back down to 2k and go up and down from 1500-2k rpm.



HELP HELP HEEEELP :<<<

I know it doesn't narrow it down but have a look at this thread. http://www.gtir-motorsport-club.com/t2701-high-idle-probs?highlight=Idle at least it gives you a lot of causes for the problem.

Will do im just thinking whats wrong ;/ all the vacc lines have been redone and worked fine etc. I could do with a second TPS and AFM and new plugs to see

It getting the air from somewhere.
I would clean & inspect all the air valves & also check all hoses-vacum lines closely, also look at dump valve as pending what type & how plumbed in they can cause serious idle issues when faulty.

Yeah i will have to triple check all the vacc lines etc, I have a spare forge BOV which i might install and see how this goes.


Link to the video of my car on idle - https://www.youtube.com/watch?v=in9m1oi20qM

Block the vacuum line to the brake booster and see if that helps.