Idling issues

[King Fisher]

Hey up chaps, Nick has a little issue with his S2. First off, the idling is a bit odd; I'll outline the problems below:

1. When the car comes to a halt, the idle drops to almost nothing (sometimes stalls), then rises up to around 1500rpm, and slowly finds its level at around 1000rpm.

2. When the brake is depressed hard when stationary, this sometimes causes the revs to drop very low, then pick up and slowly find a level again.

3. The throttle sometimes seems to stick open at 2000rpm.


The ISCV has been taken off and thoroughly cleaned with carb cleaner and a toothbrush. A new throttle pot has also been fitted. Nick's thinking servo, or perhaps wiring? Where would be best to look next before spending £££?

Thanks,

Tony

[Gerald-TVR]

Almodt certsinly a air leak somewhere between plenum and servo and check condition of base of servo could well be rotted through

[King Fisher]

Okey dokey, is the old trick of passing a butane bottle around the area going to be useful for showing up the air leak?

[Maffe]

Sounds like an air leak.
Check all rubber hoses, also check the backpressure valve for the crankcase ventilation.

[King Fisher]

Maffe said:

Sounds like an air leak.
Check all rubber hoses, also check the backpressure valve for the crankcase ventilation.

Hi Maffe, could you tell me whereabouts that is found?

[Maffe]

It´s located on the left hand rocker cover (sitting in the car looking) the backpressure valve is in the rubber hose conecting it to the rocker cover. Easy to check function by blow/suck to see if it works like it should.
Hope this made any sens

Good luck!

[Adrian@]

Funny you should mention that valve...I was sat in a foyer of the company that makes them and loud and proud, on display, was the 1 millionth made on it's very own wooden plinth!
Adrian@

Edited by Adrian@ on Tuesday 20th September 16:32

[Gerald-TVR]

Adrian@ said:

Funny you should mention that valve...I was sat in a foyer of the company that makes them and loud and proud, on display, was the 1 millionth made on it's very own wooden plinth!
Adrian@

Edited by Adrian@ on Tuesday 20th September 16:32

Sad or what!!

[Adrian@]

Norman,
I would love to think that was the case, BUT they in turn gave me a tour of the factory, supplied parts that I required FREE OF CHARGE, pulled up computer list of their redundant TVR parts and said I should email them later for a list of these items and consider bidding on them...
Adrian@

[King Fisher]

Well, throttle pot tested, it's ok. ISCV cleaned again, new gaskets applied, seems to be working. When the car is first started, it is fine, but once driven about a bit it keeps idling funny. Nick's thinking sticky throttle linkage, or maybe damaged wiring? Servo seems fine, no issues with braking either.

[techbotics]

Gerald-TVR said:

Sad or what!!

totally disagree any uk company making a million of anything should be proud, I would be.. Uk plc makes pretty much nothing these days its a real shame.

Damian S3

[Adrian@]

On topic....Double check that the vac pipe between the valve and the air box (this runs around the air box and to the valve) is not collapsing under vac.
Adrian@

[Gerald-TVR]

techbotics said:

Gerald-TVR said:

Sad or what!!

totally disagree any uk company making a million of anything should be proud, I would be.. Uk plc makes pretty much nothing these days its a real shame.

Damian S3

Yep on second thoughts your are right silly comment by me

[King Fisher]

Adrian@ said:

On topic....Double check that the vac pipe between the valve and the air box (this runs around the air box and to the valve) is not collapsing under vac.
Adrian@

Which pipe is that? There isn't a pipe running from the ISCV to the plenum?

[Adrian@]

Sorry, I thought we had moved on from the ISCV to positive crankcase ventilation (PCV) valve on the drivers side rocker cover (as mentioned by Maffe).
Adrian@