Macca-RST

Ok bit of a longish story but thought i would include everything i know so far to try and eliminate or introduce possible reasons as to why this problem exists.

From one of my previous posts i had problems with my rs turbo starting from cold! Turned out to be the cold start valve so its unplugged - ok not 100% if this is the reason that fixed the cold start problem but its working so far.

Now a week later, what happens is it still starts everytime from cold, but when the car reaches normal running temperature, it will not start again - i have to wait for the engine to cool down before it can start again.

At the same time of this happening, the car now always idles at 2000rpm, does not drop or go up, stays at those revs all the time on idle.

Im guessing the 2 might related as both problems started at the same time, but maybe not... just trying to help narrow things down.

Another problem i had, and i dont think this has anything to do with it, but i had a small fuel leak and it turned out to be leaking from the fuel accumulator, but it was leaking from the tiny screw on the bottom.
What is that screw there for? What i did was just made up some JB Weld (chemical metal) and sealed up around the screw so it doesnt leak.

Any ideas?
Cheers

tabetha

I'd be fixing air leaks first, to be idling at 2000rpm it is getting the air from somewhere, so check throttle not stuck, air leaks in pipes, loose clips etc, even the breather system pcv valve stuck open can cause this air leak, as can one way valve on servo.
If the leak is bad enough it could be causing such a lean mixture it won't fire, I assume when you say not starting you mean it's turning over ok just not firing ?
tabetha

Macca-RST

Yeh it turns over just wont fire.

When i had the problem when the car wouldnt start from cold, again i was told air leak could prob be the problem, at that time i checked every air line was secure and in good condition so i dont think it could be that since it was only a week ago i checked them all and they were all good.

Looked around a bit more on the net and found that it could be a dodgy starter motor, due to when it gets hot? Anyone else heard of this?

Again the car starts everytime from cold, but anything say above 1/4 up the temp gauge it wont start

tabetha

The starters are famous for getting cooked, but as it turns over ok this is showing the starter to be working.
Look to see that the plate in the fuel distributor is not sticking, and has not got a carbon ring around the edge, if it has get the carb cleaner out.
tabetha

Macca-RST

Had a good look at the engine today, checked all air lines again and they were secure and not leaking, found that with a leak the revs drop - not rise - so wouldnt help my high rev problem.

Throttle wasnt stuck and the plate in the distributor was clean.

Could it be a dodgy sensor?
Could it be that the car thinks its cold all the time? As ive said it starts everytime from cold, but will idle at 2000, wont it idle at those revs anyway at that temp just to help heat the car up? Then shouldnt it drop when it reaches a certain temp?

Really annoyed at it now cant find anything to do with it

tabetha

I am not overly familiar with these set ups, but think they use a air bypass for cold operation, this could be stuck, it is a valve with a pipe going to each side, and a electric feed, one side goes to filter side one to engine side, these do get stuck.
They can often be cured by putting in a sealed plastic bag and freezing them overnight then drop into a pan of boiling water, worked on my 4i.
tabetha

main rbrt

had same problem withmy old XR3i moved the battery lead from the starter up to the battery and re-routed it was fine after that hope this helps

fatmike

iTrader: (4)

turn the idle screw down slightly ?

Macca-RST

Sounds likely that could be the problem... just got it off 5 mins ago and its in the freezer now.
Will let you know if anything cures it
Cheers

Macca-RST

Right problem seems to be fixed now
problem seemed to be a bit of both - aux air valve and the idle screw.
Anyway its running great now, big thanks

Macca-RST

Spoke too soon!!
Was out in it last night and everything was going fine untill later on the revs rose up again and car wouldnt start from hot again!

Now this afternoon went and had another fiddle around.
I have double checked that air valve by starting the car, allowing the engine to go to normal temp, and blocking off the connector at the inlet (so as if the valve is closed) and there was no air passing through the hose (once when hot obviously)

I had then now set the idle screw so its not even touching the throttle position and it idles at 1000 - 1100.

It started and stopped everytime (not great though but still started) about 10 times while hot, allowed to cool down for 20 mins and tried again and still started everytime.

So i thought right why dont i make it idle at 2000 again and try start and stopping it, so i adjusted the idle screw so it sat idling at 2000, turned the car off and guess what it wouldnt start! Turned down the idle screw AGAIN so it wasnt touching the position, so its now the same as it was before when it was starting evertime and it wouldnt start again!
Now im back to the start where i have to let it cool way down again before it has any chance of starting again !

This is unbelievably confusing!

bobmadle

hi there i had the not starting from hot problem on my rs
would start first time from cold, no hiccups at all, i could leave it weeks and it would start perfect first time. but after 20 miles or so if i switched it off it wouldnt start again until i left it 10 mins to cool down
turned out to be the fuel pump, i changed that and i never had the problem again.
hope this helps

davecosworth

check the fuel pressure and also when it doesn't start remove the air filter and push the flap downin the metering unit and release now try to re start if it starts then more then its going to be a strip down of the metering unit had had this alot on the rs turbos that i had owned and i owned 9 or so