occasional hot stalling?

[NiceCupOfTea]

Took the S to work this morning after being sat for a month or so. Ran fine but on the way back I hit traffic and sat for a while. Tempnwent upnas expected and the fan cut in a cooled it down. Towards the end of my drive it hesitated/misfired a couple of times when I was driving. Temp was only showing as high as the while line on the gauge (about 3/5). Idle fluctuated a bit when in was in a queue like you might expect if there was a vacuum leak and it stalled after I braked to a stop. Restarted straight away. As I was on the drive opening the gate the idle sounded OK but then it just died. Again, restarted and drove through the gates...

Things to check? Top of the list is the idle control valve (I assume that's the metal cylinder on the front of the plenum?). Are there any vac hoses that might have split? Anything else?

[Mr Clifford]

Check injectors for corrosion

[NiceCupOfTea]

Mr Clifford said:

Check injectors for corrosion

Specifically what? Connectors? Or take the injectors out? Why do you think it might be the injectors specifically?

[TurboTony]

How old is the petrol? If the tank is reasonably low then the fuel might have gone off - the volatile stuff in it evaporates, I believe,which can give running problems. This modern unleaded stuff has a short shelf life.

Just a thought before you rip the engine apart....

[NiceCupOfTea]

I'm ashamed to say that it's 6 months old but the tank is at least half full, only done 100 miles or so since...

Would find it odd that it was just doing it towards the end of my journey having got warm in traffic. Do remember it running a bit rough on a very hot day last summer but put that down to a duff fan relay. Never got that hot though...

Does the ICV give those sorts of symptoms if it needs a clean?

[jwigglesworth]

Mine's been doing exactly the same for several years now- no idea what causes it although I think a lack of use is a major contributor as a good long blast seems to help. Does anbody know if running on super unleaded would make a difference?

[Mr Clifford]

NiceCupOfTea said:

Specifically what? Connectors? Or take the injectors out? Why do you think it might be the injectors specifically?

My connectors were corroded. When the car got hot my car cut out. When the engine was cold it was fine hot it cut out.
Garage cleaned connectors then the car has run fine for the past five years.
Sorry for the late reply.

[Spanish S2]

jwigglesworth said:

Mine's been doing exactly the same for several years now- no idea what causes it although I think a lack of use is a major contributor as a good long blast seems to help. Does anbody know if running on super unleaded would make a difference?

Run mine on super unleaded all the time, previous owner told me to. Never had any problems!

[Mr Clifford]

NiceCupOfTea said:

Specifically what? Connectors? Or take the injectors out? Why do you think it might be the injectors specifically?

My connectors were corroded. When the car got hot my car cut out. When the engine was cold it was fine hot it cut out.
Garage cleaned connectors then the car has run fine for the past five years.
Sorry for the late reply.

[NiceCupOfTea]

Hmmm, did exactly the same journey today under same conditions with the same results. 9 dry miles, light traffic, car ran beautifully. Return journey later on, heavier traffic, temp went up to the white mark and fan cut in to cool it down no problem. In fact, flicked on the override and temp was at half way mark so not an issue. Out of traffic and within a mile of home there was a hiccup on steady throttle, then at the next junction revs started hunting and I had to set the gas to keep the revs to about 2k. Seemed OK on the move again but coming off throttle to change down for a corner had to keep an eye on the revs as it nearly stalled. When I parked up the engine just stalled after a minute or so. Pretty much a carbon copy of what happened with the same journey last week.

Brimmed the tank on way home today with v-power so guessing not bad fuel/water in fuel/lowfuel level.

Safe to assume it's something under bonnet getting too warm? Even though the engine temp was reasonable i'm guessing under bonnet temp was still high. Will clean up injector contacts and clean out icv if that's the cylinder attached to the plenum after the air intake pipes. Will also take a look at the ignition amplifier as per other thread although gut feeling is it's something else...

[NiceCupOfTea]

Update:

My car has always been a bit unhappy to rev when cold - anything more than a gentle press has it pretty much stalling (like an old carb'ed car). Occurred to me that a new rotor arm and distributor cap might help both problems.

Bit of a delay as I discovered there were 2 types and Motorcraft don't do them any more.

Fitted them this morning: exactly the same. Let it idle for 10-15 minutes and the temp gauge was just starting to come up but it was still slow to rev (better than cold).

Being a modern(ish) FI engine it shouldn't have that flat spot should it? I just don't have the time to troubleshoot at the moment (hell, I have to move 2 other cars to get it out) and I know if I book it in with Dan Taylor I will miss most of the summer before I can get it in.

Any other ideas?