Pop bang- is this normal?

[Hood38]

Well the honeymoon period is over. For the first 3 weeks my 'new to me' S2 performed faultlessly and didn't even leak. Took her on a decent run to Devon at the weekend and by the time I got there the car was missing hooribly, wouldn't tick over, the speedo had packed up and the hood had started to leak!
Can't fathom the missing though. If I floor it I seem to have full power but it just doesn't want to know at anything under 80. Almost seems like the engine is momentarily cutting out. This morning she would hardly start and got me a couple of hundred yards before I turned round and climbed on board the trusty Kawasaki. Any ideas, does this ring any bells?

[Lurch]

Must be worth trying the cheap things first, plugs and leads. I have had this on other cars caused bby leads and plugs but not on my Tiv.

[WildfireS3]

Could be the Coil, when the engine warms up the coil also get really hot and the insulation inside it can degrade. But as before said try replacing the plugs and leads also.

Could be a bad earth or throttle pot?

[andyf007]

Would agree with the others, it sound like a weak spark, probably due to moisture. Try a quick spray with a water repellant on all the leads and especially the dizzy and coil.

Andy

[yellabelly]

Try this thread
www.pistonheads.com/gassing/topic.asp?t=26289&f=11&h=0&hw=throttle+pot

I also had the S3 misfiring, kangarooing and wayward idle so unplugged the throttle pot and it solved the problem. Only now have a high idle speed to contend with

[Hood38]

Well two of you were right, unplugged the throttle pot and bingo. Now idles at 2000 rpm, does this indicate another problem or is that what happens when you unlug the pot?
I looked on the parts list here and couldn't find a mention of the throttle pot or part number, anyone know the correct part no. or the Cerbera 4.2 pot no?
Big thanks to everyone on this group- have never heard of a throttle pot before yesterday so would not have guessed that in a month of Sundays. Bible now ordered and on the way!

[Roy C]

Part numbers are on this list:
www.tvrcc-south-wales.co.uk/sparts.asp#engine

The last Throttle Pot I bought was around £40

>> Edited by Roy C on Tuesday 4th November 10:14

[andyf007]

Hood38 said:

Well two of you were right, unplugged the throttle pot and bingo. Now idles at 2000 rpm, does this indicate another problem or is that what happens when you unlug the pot? I looked on the parts list here and couldn't find a mention of the throttle pot or part number, anyone know the correct part no. or the Cerbera 4.2 pot no? Big thanks to everyone on this group- have never heard of a throttle pot before yesterday so would not have guessed that in a month of Sundays. Bible now ordered and on the way!

If I unplug mine it ticks over at 750. A faulty idle control valve would cause a 2000 rpm idle. Try unplugging that too (it's the plug on the end of the round tube like unit attached to the side of the inlet manifold, just above the throttle pot). Also try resetting the ECU too.

Andy

[walsingham]

I had exactly the same symptoms and it's with my local grease monkey now... let's see if it's the same thing...