Help needed - Problem with Chimaera this morning

[evo]

Can someone offer some advice and help me out. I have a feeling the words "stepper motor" will be said so here goes. I've had my Chim for 3 months now and done about 1500 fault free smiley miles. Thought I'd use it for work as it's a nice day and on the way in heard a kind a short crack/bang so I instantley lifted off and put it in neutral doing 50-60 mph. I noticed that the revs were fluctuating between 900 and 2000. I pulled over and stopped and it was still fluctuating at 0mph. When I got to the office it seems fine, both engine temp and oil pressure were unchanged throughout the whole episode. Maybe it's a coincidence and it was a stone hitting the screen but if felt like a mechanical noise, coupled with the fluctuating revs, engine power seems to be the same. I'm going to put it on the ramps a bit later and have a look but can anyone offer any help in the meantime.

Thanks and apologies for the vague and crap description of a technical "crack/bang"

JB

[Big Al.]

"They all do that sir" idle fluctuation that is. Periodically mine has a bout of hiccups as I call them.

I normally drive through it.

As for the crack/bang? Don't know. Could just be coincidental!

[TheHobbit]

Mine did that on monday. seemed to go away, no bang associated with mine though, but as Al says, could have been coincidence.

[dannyboyo]

Any chance the bang could have been the old petrol tank vacuum thing? And because of the pressure (or lack of it) it's causing the engine to fluctuate?

Mine has intermitant stalling at the moment, but I've cleaned the stepper motor, but at the same time as I noticed the occational stall, at the same time it's been when the petrol tank has been clunking like crazy.

Or am I barking up the wrong tree!!

[shadowninja]

I find that happens if when it's cold you don't let enough petrol into the engine or labour it. Try feathering clutch more (not all the time or you'll be wanting another clutch) until it's at perfect operating temp. eg If you're doing 30mph leave it in 3rd, don't pop it into 5th.

[evo]

I'll get my overalls then....]#

Out of interest i had run it on two/three tanks of normal unleaded and last week put Shell Optimax back in (the ususal juice of preference).

Is the car telling me not to do it again.

>> Edited by evo on Friday 9th January 11:44

[SNOWY WHITE]

That's interesting, I have the same intermittent high idle problem on my 400SE, but hey if that is normal I've saved myself some money, I was just about to book it into the garage!

[evo]

Well I've had it on the lift and looked all around and theres no leaks,nothing apparent has fallen off and it's idling normally. As it's the first time I've had a look underneath it was nice to find that someone had fitted a set of AVO adjustable shocks, (thought it looked lower than normal).

Guess I'll just drive it and see.

[rat]

You'd better insure it first