Idle Sticks at 1900rpm!

Idle Sticks at 1900rpm!

Author
Discussion

steveshutt

34 posts

251 months

Monday 28th April 2003
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very easy, takes 30 seconds. The ecu is near the battery in the passenger footwell. black box about six inches square. A big thick black loom type cable goes into it with a connector about three inches long, just unplug this (clip on the side) and then plug back in.

shpub

8,507 posts

271 months

Monday 28th April 2003
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The only problem with this is that it clears the error code so that when the dealer gets it, what ever diagnostic information the ECU had stored is lost and that means the dealer may simply turn round and say "can't find a fault"! He may even charge you for the privilidge.

Resetting the ECU is not a cure as it may actually cause the unit to go into a limp home mode.

Steve
www.tvrbooks.co.uk

ray_von

2,913 posts

251 months

Tuesday 29th April 2003
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tiggsy i had a similar post on general TVR (not as much response by the way but there you go)Now dont take this the wrong way but as you said yourself you are not totally confident in your abilities may i suggest that you take it back to where you bought it and get them to sort it before pulling bits off and disconnecting/resetting stuff.Mine is driving me nuts but hopefully it will be sorted on thursday

max500

16 posts

252 months

Wednesday 7th May 2003
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Most of you chaps seem to know what youre talking about. My Chim 500 can run beautifully for 100 miles then without warning cut out altogether, re start quickly but miss and then we get the revs situation like described, but tickover at either 500 and 1500 rpm.
Would appreciate anyone's advice as its really "doin me flippin ead in".

victormeldrew

8,293 posts

276 months

Wednesday 7th May 2003
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My 500 occassionally suffers from high tickover. I take this as an early warning, as it happens when the engine temp strays over 90 degrees. Frustratingly this is when I'm stuck in traffic, when a high tickover is the last thing you want. Anyone any ideas why this would happen?

shpub

8,507 posts

271 months

Wednesday 7th May 2003
quotequote all

max500 said: Most of you chaps seem to know what youre talking about. My Chim 500 can run beautifully for 100 miles then without warning cut out altogether, re start quickly but miss and then we get the revs situation like described, but tickover at either 500 and 1500 rpm.
Would appreciate anyone's advice as its really "doin me flippin ead in".


Have you tried cleaning the stepper motor?

Andrew P

25 posts

265 months

Thursday 15th May 2003
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Just to add to the discussion.

I get similar problems with my 93 4 ltr Chimera. The idle speed sometimes sticks about 1900 rpm then drops back to about 1400 rpm then to the normal idle of about 900rpm. It will also try to stick at 1900rpm when slowing down and still in gear, clutch engaged etc.

The ECU has been disconnected as I had a problem with the central locking and had to remove the ECU to get to the central locking control unit. I have cleaned the stepper motor, throttle body etc but it still happens. I did let the car idle for 15-20 minutes after reconnecting the ECU as advised in other threads.

So my question is about the stepper motor plunger, mine is conical in shape but has a bit of a ridge around the base of the cone, is this likley to be wear and it need replacing?

Cheers

Andrew

Andrew P

25 posts

265 months

Saturday 17th May 2003
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Good news

To try and sort the idle problems I cleaned the Stepper motor - again! and set the base idle properly. The base idle screw was 4 turns out not 1.5 as the bible says for a car with catalitic convertors. I guess somebody before me had tried to get it idling proerly by messing with the base idle rather than cleaning the stepper motor.

Result is it idles smoother than ever before, the revs return to idle as they should and it is much smoother to drive in traffic.

So, it's off to Blackpool with a smile on my face.



Andrew

blueseven

27 posts

193 months

Friday 24th September 2010
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Just to reinstate this thread. I'm having the same idle problems with my 95 400HC mad and I've tried all the suggested methods (I think). Now I think I've reached the limits of my abilities - only 4 weeks into TVR ownership so still a novice. I'm going to take it to the experts - but which one?

I live north of Sheffield and I'm aware of RT Racing and Race Proved in my area. Do any of you guys have experience with either of these and can recommend either? Or do you know of any other specialist I should consider.

Cheers

Gav.

Pepsi_x

217 posts

264 months

Friday 24th September 2010
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Just to add my bit to this thread, I have exactly the same issue as Tiggsy.

On the one hand the cars revs will stick at a high figure somewhere between 1400-2000 RPM, often whilst you in traffic, usually during a gear change or if you dip the clutch and coast up to a line of traffic etc. Othertimes it will stick much higher, if for example your on the motorway doing 80mph and dip the clutch.

Most annoyingly though, and ONLY when in the usual stop/start traffic when the car is staionary the revs bounce around a bit as Tiggsy says sometimes being caught by the car at around 200RPM, and returning to 1000RPM before dropping again, not being caught and the stalling. Mine currently stalls at least twice on each 10 mile journey to work and usually more if I dont catch it first.

So far I've had a new stepper motor, leads, dizzy (and probably plugs too) and still the problem persists, so it's gonna have to go back to TVR Power again...I suspect thei ssue is something between the base idle setting and stepper motor, but who knows! Its just frustrating as hell... frown

ta
James

900T-R

20,404 posts

256 months

Friday 24th September 2010
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If the base idle setting is correct, the source of the trouble is more often than not one or more air leaks IME. Even the times I was really, really sure I had none, anymore... redface

markreilly

795 posts

171 months

Friday 24th September 2010
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Just Bought Sc-power's mod for this problem,go to www.sc-power.co.uk
Stepper motor restricter hose