General Idle speed Ulysse

[BusDriver]

Is it possible to manually adjust the idle speed on a 2.0S engine?

 

[cipher]

in a word: No.

The idle speed is electronically controlled by the ecu, therefore, is not adjustable.

Why do you need to alter it? Do you have an idle speed control issue?

 

[BusDriver]

I have an issue with the engine stalling and idling too low - and unevenly. It is entirely a case of tracking down the problem by a process of elimination. I will check and clean the idle control valve, throttle body, distributor, leads, connections, plugs, fuel filter etc. I'm sure in doing this. Last thing I want is an ECU issue, really. But...

Would an ECU from a 2.0 Synergie of the same-ish year work with it? That way, I might be able to swap them over during this fault-finding exercise to at least eliminate it from the process.

 

[cipher]

tbh, I have never tried to swap the ECUs from another make.

I would guess, that if the eingine was the same, then it should (In theory), but they may use different control protocols, so it may not.

I would work on the basis of looking at an electrical fault rather than a faulty ECU.

I had a similar issue with my 2.0l, turned out it had a very minor misfire, that was cured by imply cleaning the plugs.

I would look at the most obvious, the IACV (Idle Air Control Valve). Take this off, and give it a thorough clean. Check the spark leads, Plug condition, check for vacuum leaks, etc etc.

If after all this, then you can get the ECU tested with ecutesting.com

They can do this from £35. Fast turnaround, have recommended these guys for some years now, and they have always had a good review.

(I am not now, nor have I ever been associated with the above company, its just a compnay that I have had experience with, and would recommend.)

 

[BusDriver]

Thanks,

I'll let you know how I get on this weekend.

 

[pt108271]

This is an idle valve problem which is quite come. It just needs taken out, cleaned and put back. I can do mine in ten minutes now as I have done it a few times. If you search this forum for "idle valve" there is plently of advise for how, its how I found out!

 

[BusDriver]

Well, the idle valve actuator has been cleaned and replaced and a guy at the garage 'reset' it using his diagnostics thingy (actually a Citroen device but works on PSA engines).


And it still is playing up. Just did a 500 mile round trip. on the outward journey it behaved fine, then as it started to rain the old problem returned. Next day it went away again (it wasn't raining incidentally). Today it was raining again and the disappearing idle speed trick reappeared.

Drove 250 miles back trying not to stop. Not fun. But quick lol!

The rain thing is probably a coincidence as I don't see how it could affect the car like that.

Another thing I notice is at speed if I trail the throttle or hold it at around 3000 or less rpm sometimes it will feel lurchy and slightly stuttery. But only sometimes. Is this related or does it point to another, related issue?

 

[BusDriver]

It's all become clear. We connected it to a diagnostics computer after replacing the stepper motor and another fault revealed itself after a test drive.

The idling was still uneven and the 'lurching/stuttering' feel was still there under certain conditions. It was traced back to the oxygen sensor which plain wasn't working. Getting to this proved very difficult as it's right up at the top of the downpipe/subframe. Waited for the engine to cool (yawn). More than an hour later we (I say 'we' - it was my mechanic/specialist Pete! lol!) had replaced the ****er and now - after extensive testing over the following hour and several miles later, the problem seems fixed. And the engine runs sooooo much better; there's more ooomph and I just hope that's it. It really 'goes' now. It'll just eat up those miles in France I hope!