Cold Running?

[Batty S4C]

After a month or two of running the car in standard form im ready to get me hands dirty with the S4.
first off i have a quiery regarding cold running.
after starting the S from cold the engine will not rev until it is above 50 deg.
if you depress the throttle the engine chokes and tries to die, and if she does cut out is a bugger to start after.
once up to 50deg however runs like a dream.

any suggestions?

cheers chaps

Matt

[andyf007]

Batty S4C said:

After a month or two of running the car in standard form im ready to get me hands dirty with the S4. first off i have a quiery regarding cold running. after starting the S from cold the engine will not rev until it is above 50 deg. if you depress the throttle the engine chokes and tries to die, and if she does cut out is a bugger to start after. once up to 50deg however runs like a dream. any suggestions? cheers chaps Matt

3 main items to check are the throttle pot, idle control valve and the engine temperature sensor. It could also be the MAP sensor.

It sounds like the ecu is not enriching the mixture, which would point to it not getting the correct information back from a sensor.

Andy

[WildfireS3]

Yeah, what Andy said. Let me know how it goes Matt, as in a few week I will soon be getting dirty byu replacing the bust exhaust bits, lights and a few other things. Done the fuel sender unit already.

[Podie]

Again, I'd agree with what Andy has said.

I used to have a similar problem with mine, but since the [blatent plug] "Full Podie" at Austec [/blatent plug] , it's not done it since.

[greenv8s]

How old are the plugs and what state are they in?

[Batty S4C]

andyf007 said:

3 main items to check are the throttle pot, idle control valve and the engine temperature sensor. It could also be the MAP sensor. It sounds like the ecu is not enriching the mixture, which would point to it not getting the correct information back from a sensor. Andy

Cheers Andy.
am in the process of cleaning the engine bay to get a clearer view on things ( done twice with gunk, third time this weekend!)
i have steve heaths bible, will all the above be detailed in that?
kinda would like to DIY it because at least i get to know the car.
she is due for a service (small one, plugs, filters, oil, leads) and may do it myself.
thanks for the info guys

[andyf007]

Batty S4C said:

I have steve heaths bible, will all the above be detailed in that?

Pretty much, the rest is on here somewhere.

To check the throttle pot, simply unplug it, and try a cold start and see what happens.

Same with the idle control valve. Mine's unplugged at the moment and, while it does appear to not increase the engine revs during a cold start, it doesn't cause the problems you have.

The engine temperature sender would be my favourite, but I'm not sure if just unplugging it will tell you anything, as I've never done it, but it's worth a try. In fact I may unplug mine tonight, just to see if it will re-create your problem.

Andy

[Batty S4C]

andyf007 said:

Batty S4C said: I have steve heaths bible, will all the above be detailed in that? Pretty much, the rest is on here somewhere. To check the throttle pot, simply unplug it, and try a cold start and see what happens. Same with the idle control valve. Mine's unplugged at the moment and, while it does appear to not increase the engine revs during a cold start, it doesn't cause the problems you have. The engine temperature sender would be my favourite, but I'm not sure if just unplugging it will tell you anything, as I've never done it, but it's worth a try. In fact I may unplug mine tonight, just to see if it will re-create your problem. Andy

cheers mate

Fantastic guys
really make owning a TVR so much more of an enjoyable experiance (not that it isn't in the first place)

[andyf007]

OK, unplugged the engine temp sensor this morning and it won't start. Once up to 50+ degrees I can remove it ok and amazingly my idle control switch then starts functioning correctly (returns to correct idle revs and not 1500). I think I'd better get one on order. Are you having any joy yet Batty?

Andy