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THE REAL BORIS wrote:My (SE) idle has started to rise up to 1200 rpm after it reaches operating temperature. Not all the time but often enough now that I notice it happening more frequently. Revving it still sees it fall to the 1200 level. If turned off and re-started, then it settles to the normal 850 every time!

This looks like an ECU glitch; any offers?

Mods. stock inlet with GFB bypass, mbc, FM downpipe & Begi tbe.

Idle sticking to 1200rpm happened to me once, I found that my resting idle wasnt great. I re-adjusted the resting RPM to 900 via the air idle screw (GND and TND jumpered whilst doing it) and then reset the ECU. Problem didnt return.

Other possible reason for idle sticking:

Vacuum leak, lean at idle, gunk in the throttle body, throttle cable/spring/butterfly catching.

If you have a CEL (Check engine light) have it read via an OBDII scanner, that will help narrow it down.

I was fitting a cruise control to my SE and when messing around with the clutch switch for disengaging, found that it inputs to the ECU.

When in gear at idle without clutch depressed, the idle is raised, presumably to avoid stalling. When in gear and clutch depressed, idle is normal.
I found this out by disconnecting the switch to see what it did. ( I ended up putting in a separate switch and leaving the OEM well alone.)

Might have something to do with your problem, check it out for adjustment etc..

Regards, Rob.

THE REAL BORIS wrote:any offers?

I wasn't looking for an SE, but if you need to get rid of it... $10K?

Boags'MX5 wrote:

THE REAL BORIS wrote:any offers?

I wasn't looking for an SE, but if you need to get rid of it... $10K?

*gets fishing rod out*

Upgrading from the SP???

My car has done exactly the same thing. It did it once and then didn't do it again for about 12 months, then did it a few more times then stopped doing it for a few months then started again then stopped. It's been fine for about 18 months now. Sometimes giving it a rev would fix it but the only sure way to fix it was to turn off the engine and restart it.

I tried adjusting the throttle cable, looked for vacuum leaks and cleaned the throttle body but none helped. Yes, it is a bit annoying in stop go traffic.

sabretooth wrote:Upgrading from the SP???

I don't have an SP, can't afford one. So I thought I'd aim a little lower...

THE REAL BORIS wrote:My (SE) idle has started to rise up to 1200 rpm after it reaches operating temperature. Not all the time but often enough now that I notice it happening more frequently. Revving it still sees it fall to the 1200 level. If turned off and re-started, then it settles to the normal 850 every time!

This looks like an ECU glitch; any offers?

Mods. stock inlet with GFB bypass, mbc, FM downpipe & Begi tbe.

Mine did the same thing, it ended up being some servo motor used for the auto rpm adjustment when cold/air con that sits under the throttle body. Apparently it gets gunk in it and locks up intermittantly. Sits on the bottom of the throttle body and you just spray a heap of non plastic damaging carby cleaner down it's guts to loosen it up.

Sounds like the ISC/ ICV.

Jules

jules wrote:Sounds like the ISC/ ICV.

Jules

NA's are vacumn dríven, the NB's are servo motor adjusted.

ooooohhhhh, well I'm not that up to speed on them-new-fancy-models


Jules

jules wrote:ooooohhhhh, well I'm not that up to speed on them-new-fancy-models

Time to upgrade then!

Craig wrote:

jules wrote:ooooohhhhh, well I'm not that up to speed on them-new-fancy-models

Time to upgrade then!

Let me know if you find the Unicorn

Jules

Pfffft!

Hmm...thats a little strange that it would affect ur idle. if it were holes in the piping after the AFM, I could understand...but before it?