"Stuttering" at the cruise

[whitey]

Joolz, does this mod work on the speed 6 engine too ? I had the throttle pots replaced 1000 miles ago, and it now hunts and stutters when hot on part throttle.

Cheers
Whitey

[joospeed]

got to be clear here guys .. it's not a wonder cure for all running faults, if there's a fault it needs fixing, if there's a throttle pot fault these mods will work - if it's a lambda fault no amount of throttle pot fiddling will cure that.
Cost .. hmm - how much would you pay to ahve your car running better than it does now? .. 100 pounds .. 200 pounds .. 500 pounds ... ??

[cinman]

Well I've been to APM on Saturday past, met some top blokes and saw some nice motors. Andy certainly knows his stuff and I'd recommend the place to anyone.
As for the car, still stuttering (throttle pots didn't seem to be the prob) - it seemed two of the cylinders weren't actually firing at all!!! New plug didn't resolve, so I left having to sort out some HT leads and plugs all round as the next stage in trying to identify the problem. Andy reckoned it might be a crank sensor, or the coil packs, but either way should replace ageing HT leads anyway and plugs were not "normal" ones either. Will do plugs 'n leads this week and see how that goes before spending out any more.
The pain in the a*se bit is that I can't drive the car now I know it's not firing on all 8 cylinders, so its off the road until fixed .... BUGGER!!!

>> Edited by cinman on Sunday 27th April 09:42

[mudstud]

Seeing as we are talking about pots...had a 400 mile return trip from Aberdeen I was looking forward to (apart from all those camera's around coldstream!), however as soon as I set off when I put my foot down it felt like I was only running on 4 cylinders. Joolz confirmed that one pot was cream crakered. Alls well that ends well however I still feel done out of a fine cruise!

[cinman]

I'm due to replace the two coil packs, all 8 sparks and all 8 HT leads this week, one evening weather permitting (I'm not rich enough to afford a garage) - I'll keep you updated on whether that fixes it or not. As a matter of interest, could the ECU be problematic/cause?

[darreni]

The ecu can cause problems, but more likley it has stored fault codes from duff sensors/pots etc. ( TVR say a fault code will also be generated if you unplug any sensors with the ignition on )
You will need the dealer software to reset the codes & set up pots correctly.
Darren.

[cinman]

Apparently my ECU isn't "remembering" fault codes - it sees them, then forgets it saw them (if you know what I mean?)

[cinman]

Well, I replaced the coil-pack for right-side bank of cylinders (the rear pack) and lo-and-behold ... smoother running straight away? Haven't even done plugs and HT's yet, so it may be even better after that?
As a note, don't attempt to replace the coil pack unless (a)you know what you're doing, and (b) you have the tools to hand. I had neither, but went ahead anyway, and it took me 3hrs - but worth it in the end for the result is brilliant.
With HT leads, they seem to have differing lengths, because some of the new leads I have don't stretch round the cylinder head to the plug ... yikes!
Also, the plugs seem to sit in these deep recesses with very little "room" around them to fit a plug wrench into ... that's why mine haven't been changed yet!

[gazzab]

so is it firing on all eight cyls now?

[cinman]

Yeah, seems to be now. I'm going to get right length HTs this weekend, and get the plugs switched over too (shouldn't take more than half-hour I reckon :-) and it may "clean" up the running even more, even if by a little, or even if by "placebo" effect if nothing else - (plus nice clean leads look nice!)

[mlumb]

halfords do a plug socket(10mm fit)in their professional range which fits.

you'll need a 3/8 drive jointed extension too.

mike.

[cinman]

Thanks Mike - that's good to know. I'll secure one this week.