Hi guys,
I fitted my 51mm throttle body yesterday (cheers Justin) and have got a bit of an idle problem now. When you start the car it idles between 600 and 800rpm and is on the verge of stalling. If you touch the throttle, it cuts out as soon as the revs die back down.
I've tried adjusting the idle screw but it doesn't seem to do much. If I turn it all the way in, the car stalls so I don't think there's an air leak.
Has anyone got any ideas on what I need to look at? Ignition timing is at 6 degrees as this was checked a couple of weeks back when trying to sort a misfire (turned out to be plugs). I'm trying to get a chip sorted from PPP to suit as I don't think the current one is helping matters.
The idle switch engaging?
Throttle cable probably too tight.
Sorry how can I check if the idle switch is engaging?
I don't think the throttle cable is too tight but I'll check this tomorrow, cheers. How much slack should there be in it?
Does it idle ok with a standard throttle body fitted?
Yeah it was fine with the standard throttle body. Sometimes it would jump up to 1200-1500 when sat at the lights and very occasionally cut out but was always fine from cold. I put those niggles down to general G40 quirks though? The others I've known have done the same thing every so often.
you can hear the switch click as the throttle is pressed slightly and then released.
not sure what you mean by g40 "quirks", they should run as smoothly as any other car, idle jumping to 1200-1500 and cutting out isn't normal. even my turbo one doesnt cut out (idle sometimes sticks because of the 51mm throttle body).
have you set the idle speed with the car in service mode (blue temp sender disconnected?)
Every G40 I've been in has cut out now and again so I assumed it was something they all did, I stand corrected :)
I've ordered a new chip from Andy so I'll try and get the basic setup checked once this arrives. The ignition timing was checked in service mode on the old throttle body. However it kept cutting out with the new one when I was revving the engine to get it into service mode to do the idle speed.
I'll update this once I've received my chip and done some more tests, thanks for the help so far!
Sorry, similar situation to you Tez so thought i'd post in here, Mine sometimes sticks at 2k rpm, hold it on the clutch so the revs drop and it sorts it.... also sometimes hunts between 1000 and 1500, rev past 2k and let it drop and it often sorts itself out.... any ideas?
Every sensor is within margins and timing is 6 deg.s same as tez :-)
Quote from: POLOMON on September 19, 2012, 11:40:57 AM
Sorry, similar situation to you Tez so thought i'd post in here, Mine sometimes sticks at 2k rpm, hold it on the clutch so the revs drop and it sorts it.... also sometimes hunts between 1000 and 1500, rev past 2k and let it drop and it often sorts itself out.... any ideas?
Every sensor is within margins and timing is 6 deg.s same as tez :-)
have had exactly the same spent ages trying to sort it gave up in the end think jezza had this problem for a while not sure if he's cured it now.
Oh god, ive got no chance then haha. Its bearable tbh, more an annoyance tbh with you, i did read yourself and jezza had the issue, wasent sure if a conclusion was met. Obviously not. :-\
Usually this behaviour is caused by one, some or all of the following:
Air leak (auxiliary air valve pipework is a favourite)
Sticking throttle butterfly
Incorrect ignition timing
Incorrect idle speed setup
Throttle cable snagging
Idle switch not engaging, or not working
Yeah mine is still playing up and not sorted but with andy's list mine is as follows
Air leak - could be but all mine is silicone and tight
sticking butterfly - could be but had it off and it looks fine
ignition timing and idle is fine as andy mapped mine
throttle cable is fine and free
idle switch - you can hear it making the microswitch
I thought due to the little hole i found in the body this might be the cause but justin said some are like that and he sorts them out usually with liquid metal.
If i drive mine hard all the time its fine but when i come to stop,using the gears, its usually fine but when i brkae hard not using the gears if its above 2000rpm then i find that is when it does it. Its bloody annoying and i feel like people are looking at me.
If i go to reverse and give it a slight rev it does it again. I usually sort it out by reving it 3 times.
When i did the mapping with andy it was fine and we set up the idle but i remember about 2 mins after setting it up it then did it. Andy said thats lucky its doing it now, not before we setup idle, but he did say its usually a sticky butterfly.
Quote from: Jezza-7 on September 19, 2012, 08:03:37 PM
Yeah mine is still playing up and not sorted but with andy's list mine is as follows
Air leak - could be but all mine is silicone and tight
sticking butterfly - could be but had it off and it looks fine
ignition timing and idle is fine as andy mapped mine
throttle cable is fine and free
idle switch - you can hear it making the microswitch
Air leak - mine are brand new braided hoses for all vac's and new pipes.
Sticky butterfly - did it on the 48mm body and the ported one.
ignition- is bang on, sure of that.
throttle cabe- is a new genuine one
Idle switch clicks as usual.....
So that rules my suspects out
Air leaks come from more places than vacuum lines, injector o-rings are a favourite too.
Mine should be good as you serviced them last march.
I just put up with it, all the gaskets are new as well and im using mikalor and jubilee clamps on everything else.
What effect would a dodgy clogged up ISV have on this? I know it opens when it's cold but what if it can't close properly?
Quote from: Yoof on September 20, 2012, 06:24:14 PM
Air leaks come from more places than vacuum lines, injector o-rings are a favourite too.
Ive new 0-rings on mine, had my injectors cleaned and inspected at work and they had a small rebuild until i can get G60's.
Im on mikalors also Jezza, no boost leaks anywhere atall, smear of silicone and a mikalor made sure of that. Had the boost valve (dont remember the exact name) on the throttle body shut for 2 seconds and gone around and squirted WD on all joints to be sure.
10 points to Yoof. I checked the throttle cable today and it was too tight so the idle switch wasn't engaging/disengaging. I slackened it off and had a quick play with the idle screw and all seems fine now.
I'll update when I get my chip as I'm still reluctant to use it without at risk of running lean but it seems sorted for now :D Only thing is that it doesn't stall when I tighten the idle screw all the way in which makes me think I have an air leak somewhere?
Cheers guys.
Was it up to full temp when you tightened the screw in? If the engine was cold and the auxillary air valve was still open, this may have been enough to stop it stalling.