Fast idling problem

[No.8-350se]

Hello everyone,

I'm a relative new comer to wedge ownership, I bought my 1990 350se about 4 years ago now, and only used it for the first year, since then, it's been tucked away in my garage.

I now want to recommission the car and start carrying out all those tlc jobs these cars need/deserve.

My problem is, or one of them, I reconnected the battery, disabled the alarm and turned the key, and to my amazement, it roared in to life, the thing is, it kept roaring at a constant 2000rpm.

Having regained my enthusiasm for the car, I've been regularly browsing through the threads on this forum, and now ask if anyone can shed any light on the likely causes of this fast idling problem.

All suggestions are welcome.

Thanks

Jerry

[pwd95]

If it's a 350SE it will most likely have the 'Hotwire' injection system. If so it will have a 'stepper motor' on the back of the plenum. Unscrew it & give it a good clean inside with a rag with some petrol on. Clean the threads too. When you put it back in just remember it has to be air tight.


http://www.car1.clara.co.uk/tvr/stepper.htm

BTW Welcome & get your name down for the Wedge Fest.

Edited by pwd95 on Wednesday 10th March 22:21

[No.8-350se]

pwd95,

Thanks for the advice and especially the photos illustrating the whereabouts of the potential
offending item.

[duncscz]

Throttle cable or throttle linkage sticking ?

[pwd95]

Crikey Jerry, just looked at your profile pic, what a stunning looking Wedge.

[No.8-350se]

duncscz,

Thanks, I'll have a good route round and just make sure things are just how they should be.

Jerry

[No.8-350se]

Thank you,

But you know as well as I do, sometimes photos don't tell the whole story.

What I can say though, It's not in bad shape, the body work has had some paint and is probably too good to warrant further work. However, the carpets are rotten, which is something I want to tackle this year, as when I remove the sills during the first year of ownership, the carpets just crumbled -but these can be replaced.

The other thing that has deterred me from using the car recently (apart from 3 young children) is the brakes. They are the original solid disc configuration, which believe me, are scary if you need to stop in hurry. I'm looking at going for the vented granada set up, hopefully this will be an improvemnet at reasonable cost.

[mac123yre]

I had the same problem and also erratic idle, but a good blast out was the cure so try a good run out

[No.8-350se]

Yeah, I think your probably right, but I'm afraid there is no MOT TAX or insurance on the car at the moment.

I'm hoping, certainly to sort the brakes, before even contemplating putting it back on the road - as it's no fun wondering if your gonna stop, when you need to.

[redwedge5]

I used to own 350SE no 5 and the standard brakes were very poor considering the power available. I went for the Granada ventilated brake option which also involves different calipers/pads, but they were all readily available as outright purchases and quite cheap. These along with steel braided hoses brought about a definite improvement. They were fitted professionally which was what cost the most - mainly the hours getting the rusted old hoses and parts off.

[Wedgester]

No.8-350se said:

Yeah, I think your probably right, but I'm afraid there is no MOT TAX or insurance on the car at the moment.

I'm hoping, certainly to sort the brakes, before even contemplating putting it back on the road - as it's no fun wondering if your gonna stop, when you need to.

Jerry,

I'm also in Ipswich and guess what, I have 350 SE No.9. When you finally get yours fully up and running again and its been fettled, do drop me an E-mail and we can meet up and maybe go for a quick blast. It would be good to reunite a couple of these scarce beasts!

Keith

[dickieandjulie]

Keith/Jerry

I was just about to comment about you being neighbours!!

Enjoy

Richard (ex owner of no 9)

[eesbad]

dickieandjulie said:

Keith/Jerry

I was just about to comment about you being neighbours!!

Enjoy

Richard (ex owner of no 9)

8 and 9 both in Ipswich! How spooky is that?!

They do say Wedgedom is the Dark Side after all...

Edited by eesbad on Thursday 11th March 19:58

[No.8-350se]

I agree, it's a nice coincidence that these consecutive no's are local.

I saw one of your earlier posts, where you state you are using our local
TVR dealer, how did you get on with them? - the reason I ask, is that I
tried to source a part (I think it was a water pump), but at the time they
didn't really seam that interested in catering for car of that age, I must
admit this was going back 3-4 years, when perhaps, there was more money about
and sales of modern TVR's were bouyant.

[jmorgan]

Another source of idle issues on a hot wire I had was the throttle pot setting. Easy to check but do not have the destruction to hand at the moment.

[No.8-350se]

jmorgan,

Thanks for the info - any chance of locating the
destruction procedure?

A note, to all who have been kind enough to reply,
I'm going to investigate all of these possible
remedies at the weekend - hopefully I'll be able to
let know the cause of the problem.

Thanks

Jerry

[jmorgan]

Jerry, stuck in some hotel so unable to check the file and where I got it but a quick google and....
http://www.g33.co.uk/fuel_injection.htm

Follow the link to the PDF.

Hope the owner of that site does not mind. No links to them myself. There is a PDF with what appears to be the same as what I have back home. You can get at the connectors on the throttle pot with some croc clips and suitable wire or thin probes.

This looks useful as well.
http://www.britishv8.org/Articles/Rover-14CUX-EFI....

Usual caveat for it being suitable for what you have, better check and check again.

[No.8-350se]

jmorgan,

Thanks for these links, very informative.

Jerry

[No.8-350se]

Following the advice on the stepper motor, I removed it today, and sure enough it was very sooty.

Having cleaned the piston/spring parts of the stepper motor (visible areas only - not fully extended or completely apart) and the threaded cavity with a petrol soaked rag - (I've had a go at attaching before & after photos) - I re-fitted it, unfortunately, the gasket washer fell apart, so I used some gasket sealer to create an air tight connection, just to see if there was any improvement - the revs had come down to about 1100 rpm, which I think, is still too fast.

Coming out from the other side of the plenum, is rubber hose, I sqeezed this and the revs dipped even further, so I thought I'd have a go at turning the air screw on top of the plenum, to check, how many turns it took before it was fully home, it was about 2 1/4 to the home position - this made a slight difference (tick over now approx 1000 rpm).

I have reset the air screw to the position that I found it at, but I'm wondering if the there is a specific number of outward turns it should be adjusted to, and whether, I should allow the stepper motor to fully extend and then clean it thoroughly.

Any thoughts?

Jerry

[pwd95]

I'm sure the stepper is the only thing that controlls idle on the hotwire system. It just screws in and out to vary the amount of metered air that goes in.