This has come up many times but I'm too lazy to do a search.
My car is fluctuating between 900rpm and 600rpm at tickover, but it only does it when the engine is warm.
I've cleaned the idle actuator thingy that attaches to the intake manifold, gave the throttle body a major cleanout with solvents to remove the oily grime and there isn't any air leaks I can see, in fact all the hoses etc look good.
What is wrong ????
My car isn't using any more fuel than usual.
I know i,m tempting fate here but i,ve never had any idle ,rough running,miss firing problems all i seem to get are the conventional things that break(apart from the ignition amplification modules(cheers wrinx),knocking gearbox,creaking suspension,oil leak)i wish i,d never replied to this post,i,m getting depresed
The lumpy idling is back again. It was evident at the rolling road sesh I just did. The car seems to be running a little lean according to the dyno techy stuff. Richening the idle mixture doesn't make a differnce so it must be another problem causing the revs to fluctuate.
It's a different system on the 8v, the probe is part of the AFM. I have readings for what should relate to rich and lean across all the pins, they all point to lean(ish) or richer when I turn the knob and they are stable.
Jack, yeah it does, I was suspecting this but just needed someone to say it is this.
Wrinx, the lambda is only 4 months old. I have another good one that I can swap if all else fails. The AFM ????..........Hmmmmm........my last one went boobs up but it affected the car right across the rev range and run rich. The car is really smooth just now. As I say it only happens when the engine is just below 90șC. I seem to remember the car doing it when I first bought it. It stopped when I put in Super. I'll give that a try, if it works, then I'll just put up with it as a "feature" of my highly tuned motor...............
Changed the lambaada probe last night (again). Should I notice a difference straight away or will the ECU have to relearn ???
Just the car did it's funky idle dance on the way to work this morning so I don't think the new probe has cured it. Only thing left is the AFM....and I've replaced that TWICE already due to poor running
Well a replacement idle valve is on it's way to me (Thanks Nordic for the contact).
I took mine apart and cleaned the electrical connections inside. I was a bit concerned by the rattling that the valve made when I moved it.
Speaking to the guy who is sending me the replacement, the rotor is probably gone. The car ticks over fine if I disconnect the valve, but a little high.
Hopefully this'll do the trick.
It controls the amount of air allowed to bypass the throttle butterfly which in turn controls the idle speed (700 to 800 is the target I think). The type we have uses a rotating spring-loaded valve and returns to the closed position (I think...) unless driven open. Tends to be a wee bit susceptible to crud accumulating and making them stick. Other common type is a stepper motor that can be driven both ways. Really early ones were just a bi-metal spring that rotated a slotted disc. Open when cold, closed when hot. Didn't give any active control of idle though.
There, probably way more information than you wanted, just hope I got it right
Yeah you're right. I have one from a 75 which is a two wire jobby so I can't use it.
My car is idling better thanks to the "new" valve.
BTW, I've discovered how to adjust the idle speed. If you wanna know how, give me a PM.