HELP needed IDLING issues?

Thu Apr 24, 2014 3:14 pm

Issues are, car started coughing once started, things I have done so far,

Changed the blue plug,
Rebuild the injectors, seals etc
Checked Air leaks
Check the fuel pressure regulator, by disconnecting vaccuum hose and letting the revs increase significantly.
Checked the battery reading 12.5V - once started peeks at 13.9V therefore the alternator seems to be charging it.

Problems I have been having.

Car will hold its idle when it is started, once I would select 1st, it would drop in revs. If I was to turn on the lights, or heater it would persist in dropping revs, right down to 500rpm, when it should stick at 780..

The car seems to struggle in high hears at low revs. It almost feels as if the brakes are sticking or something is holding it back when you put the foot down in 1st / 2nd. I am planning on giving it a coolant and oil change at the weekend as the car has been lying for 7-9 months.

Throttle cable looks like it is stretched, however after tightening it, it does its job, the throttle body also seems to be sticken ?. I have already cleaned it out several times with carb cleaner, to which you could eat your dinner from it, there is not excess dirt anywhere for the butterfly flap to stick.

Really starting to get peed off with the idling tho ?.. The car almost stalls itself when you go to take of.. I dont want to keep having to put pressure on the pedal to keep the revs held. Can anyone offer advice ?

Thu Apr 24, 2014 4:08 pm

First off, which engine and year of car are we talking about, and is it manual or automatic?

Thu Apr 24, 2014 8:28 pm

Throttle position switch isnt sending an idle signal.

Wed Apr 30, 2014 5:16 pm

318i, manual ? is there any quick fix for the throttle positing switch, or is it a matter of buying a new one

Wed Apr 30, 2014 5:28 pm

They can usually be cleaned out with carb cleaner or similar - you want to remove all the oil that gets into them, then ensure it's set up right; you should be able to hear it click as you move the throttle off its stop.

Wed Apr 30, 2014 6:01 pm

I have a similar issue and want to give mine a clean.
How do I get at it?
(I have lpg installed blocking access from the side)
Thanks,

Wed Apr 30, 2014 6:21 pm

I have checked for continuity, it flags up 0.4 just after i put the throttle full down. However on the other side, there is no change, when i push the accelerator etc. Also there is no clicking

Wed Apr 30, 2014 6:28 pm

Well, it must be closing if it drops to 0.4 ohm - presumably, it measures infinite (open circuit) when the throttle is fully closed? There shouldn't be any change - it is an on/off switch.

The clicking is usually very quiet - you'll have to put your ear close to it, or use a stethoscope.

Wed Apr 30, 2014 7:24 pm

Speedtouch wrote:Well, it must be closing if it drops to 0.4 ohm - presumably, it measures infinite (open circuit) when the throttle is fully closed? There shouldn't be any change - it is an on/off switch.

The clicking is usually very quiet - you'll have to put your ear close to it, or use a stethoscope.

I think the 0.4ohm is probably referring to the WOT switch.

Take the whole throttle body off, complete with TPS. There's no need to remove it from the TB to drill and clean it.

Wed Apr 30, 2014 10:02 pm

wheres the best place to drill Brian ? I had it off last week, having no carb cleaner i used petrol, but couldnt get the case to split. Simply detached it from the TB and poured the fluid through the hole for the shaft.

Wed Apr 30, 2014 10:22 pm

Drill right in the centre of the circular part on the underside of the case. Don't let the drill bit go inside.
The microswitch inside is an enclosed type, so it might take a little while for the solvent to flush the oil out of it.