Idling issues on start up..

[Griff Boy]

Hi Guys,

I have an idling issue on my 96 griff 500, when started from warm or hot it idles slightly eratically for the first few minutes constantly dropping to below stalling point, until a few revs are employed (if you must, sir!)and then she evens out back to the normal idle point. This makes manouvering difficult as you have to keep a constant light pressure on the throttle.

I don't know if it relevant, but my car suffers from a hot start problem, where the engines turns very slowly, as if a flat battery (I have an extra earth strap from the excellent Mr beer waiting to be installed) are these related?

Thanks

Ian

[bluebottle]

Sounds like the stepper motor needs cleaning me

[Griff Boy]

bluebottle said:

Sounds like the stepper motor needs cleaning me

Thanks for the advice BB. Tried that last night, stepper not too dirty, although apeture it screws into was really coked up. Cleaned both and refited, unfortunately, still the same problem. One minute it will idle and run perfectly, next it will try to stall and become very lumpy / kangaroo like and low speeds. Keeps alternating between the two.

Do I need to reset the ECU after this clean for it to make a difference?

The Stepper has a spring loaded end, that has a very small amount of movement, is this normal?

Thanks for the help.

Ian

[Griff Boy]

Thanks Quinny, will try that this weekend.

When I took it apart last time, the stepper itself was pretty clean, but the housing was really coked up (maybe previous owner tried same thing, but didn't clean housing???) anyway cleaned both as much as possible with white spirits.

Unfortuantely, I don't know anyone near me, I live in NE scotland, and nearest Griff to me is about 80miles return trip. As the problem seems erratic, could it be the electrical connecter to the stepper has a slight fault?

Cheers for the help.

Ian

[captiv8ed]

I've just fitted a new cam and had this problem on startup. I thought I'd got my ignition timing wrong, but no. The ECU needed a damn good resetting at. Just unplug your ECU for a few seconds and plug in back in. Mine ticked over lovely after that.

[bluebottle]

Griff Boy said:

Thanks Quinny, will try that this weekend.

When I took it apart last time, the stepper itself was pretty clean, but the housing was really coked up (maybe previous owner tried same thing, but didn't clean housing???) anyway cleaned both as much as possible with white spirits.

Unfortuantely, I don't know anyone near me, I live in NE scotland, and nearest Griff to me is about 80miles return trip. As the problem seems erratic, could it be the electrical connecter to the stepper has a slight fault?

Cheers for the help.

Ian

I'm sure there must be a LandRover or Range Rover garage nearby that will have a stepper motor and a fault code reader (which would tell you if its a faulty Lambda sensor)

[Griff Boy]

captiv8ed said:

I've just fitted a new cam and had this problem on startup. I thought I'd got my ignition timing wrong, but no. The ECU needed a damn good resetting at. Just unplug your ECU for a few seconds and plug in back in. Mine ticked over lovely after that.

I will give this a try first, just to see what happens... always taught to try to the cheapest easiest fix first!

I don't know if it is relevant, but I amdue to replace the exhaust manifold gaskets, as they are blowing, would this have an effect on the problem?

[captiv8ed]

Can't see it would, just an annoying noise.....

[hugepiece]

its also worth putting some PTFE tape around the stepper motor before re-screwing in. My old chim had the issue and this fixed it, must have been a slight air leak!

[350matt]

If the car has lambda sensors and the head to manifold gaskets are leaking then it is possible this will effect the running as fresh air will be pulled in giving an artificially lean signal at the sensor which leads to the ECU richening things up = bad running.

Are the plugs sooty black after the rough running?

Matt

[Griff Boy]

hugepiece said:

its also worth putting some PTFE tape around the stepper motor before re-screwing in. My old chim had the issue and this fixed it, must have been a slight air leak!

Ah,hadn't thought of that, did not want to tighten it up any more than 1 nip past hand tight when I refitted it, as it looked fairly easy to break the plastic. Will try that solution as well. Cheers

[Griff Boy]

350matt said:

If the car has lambda sensors and the head to manifold gaskets are leaking then it is possible this will effect the running as fresh air will be pulled in giving an artificially lean signal at the sensor which leads to the ECU richening things up = bad running.

Are the plugs sooty black after the rough running?

Matt

Not sure Matt, it is a 96 500, so assume it would have lamda sensors, will take some plugs out this weekend and check. Thanks

[350matt]

All the 500's have cat's so it'll have lambda sensors

Matt