Idle at 1500-2100 rpm

[Stumpy Nugget]

Another case of if it aint broke dont touch it.

Fitted a 52mm TB and followed step by step instruction in doing so. However, I am left with a car that idles (more like blips) from 1500 to 2100 RPM. Have looked about for potential problems? Before I go back and try sticking on the 48mm TB again. Anyone got any ideas that would help correct this.

its a 2001 S2 Kseries.

Is this to do with the TPS needing reset or the ECU needs to learn something?

Any help appreciated... Thanks.

[Ferg]

There's a process for calibrating the sensor which involves pumping the accelerator. You'll find it on SELOC somewhere, can't remember the specific process.

Maybe that might help??

Process:
http://wiki.seloc.org/a/Idle_Air_Control_Valve

[Stumpy Nugget]

I have tried that.. swith to position ii then pump pedal 5 times, then power down and wait 30-40s.. But nothing... same problem. Unless there is something specific for my car and this is incorrect?

I am thinking the TPS could be gubbed on the new part... Does anyone know if the old TPS from the old Throttle body could be swapped to the new one? or is that not a good idea?

[Ferg]

this might help?

http://forums.seloc.org/viewthread.php? ... pid4413332

[Stumpy Nugget]

this might help?

http://forums.seloc.org/viewthread.php? ... pid4413332

Cheers for the link. I had seen that but I am not sure I have the same issue. The car is pulsing the revs which tells me that it is trying to compensate for something and then when it revs above 2K it cuts the revs back to 1500rpm.. To me it sounds like there is a fight going on between the TPS and the IACV... My Limited skills and knowledge in this area do not help... will keep looking for answers.

Thanks

[Rich H]

TPS should swap over no problem.

Other things to check - does the new throttle close and seal properly? Gummed up with soot? I suspect it might be sticking open.
Is the IACV gummed up with soot? Take it off and have a poke about too.

The car will take time to learn it's new idle control IIRC - but that might be an urban myth...

[s29ttc]

When you take it off and poke about watch it does not spring out. When I was cleaning mine I was told to switch on and off the ignition so it moves and you can clean all about but there was no mention of hold onto the top so it doesnt spring away

[Stumpy Nugget]

Cheers guys...

I found this which is interesting reading and similar to what I have..

http://www.picoauto.com/tutorials/lotus-elise.html

Points to a gubbed TPS...

I hate everything electronic..

[Rich H]

Swap the old one in

[Stumpy Nugget]

*****WARNING STRONG STUPIDITY CONTENT ******

Sorted out the problem... basically the cause of the idle issue was a gap between the TB and its mounting point. The reason for the gap was that I had not noticed that there is two plastic parts held on by the bottom inside screw resulting in 1 sitting between the TB and the mount... result - excess Air intake and the ECU must have been going nuts meaning the revs were all over the place.

Anyway, sorted it by fitting the TB in the correct fashion and it is running perfectly.

I learned loads today about TPS, IACV and TB's.. I also learned that I should stay away from the spanners..

Cheers for the help guys.

Just wait until I try and fit cams...

[Ferg]

excellent, glad it's sorted..

[Rich H]

Cams is easy...

[Shug]

...when you tighten the crank bolt using the valve/piston interface, eh Rich?

[Rich H]

And still going strong - maybe we should write a how (not) to?