Ready to pull my ruddy hair out.....Idle jet

[Harrison01]

Cars now been on the road for nearly 3 months and for all of these 3 months the car has been running crap. whether im starting it from hot or cold it always runs on 3. Ive replaced the cap and rotor arm, checked the timing numerous times, on my 2nd set of plugs and my 3rd set of leads.

i could come up to a junction or be starting it up and the cars revs would drop to 800-900 then finally drop completely and stall. when sat at lights i have to keep my foot resting on the throttle to keep the revs up. ive adjusted the rev adjustment screw but all this does is make it idle at around 1700-2500. soon as i tweek it down it idles back at 800-900.

ive removed the idle jet and cleaned and cleaned and removed it countless times. i even went as far as searching all the boards for an answer. ive tried it running with ptfe tape on the threads of the idle jet, tried diff size o rings and even removed the torpedo to see if it makes a difference which it doesnt. all the little holes are clear.

I have had the car running and 1 by 1 removed and replaced the leads from the top of the cap and know i have a spark to each lead, then done the same to each plug and rested the plug on the water pump housing and im getting a spark on each plug.

This is now starting to really pee me off so can anyone help..

[Matt@CodeRedMotorsports]

Is your mixture screw still in the carb base?

[HULK]

Are your restrictors still in the breather pipes, have you also checked them for splits??

[Harrison01]

yeah still got the mixture screw in and the breather restrictors are in place and not split.

[Spooky]

dump valve leaking ? could be a vacuum issue...

[Thundercat]

Just had the same issue with two of my carbs, both had this problem. Found that there must of been some crap in where idle jet is fitted, unscrewed jet and sprayed in some wd40 with straw fitted. cleared fault and idled a dream from then on.

[Harrison01]

Sorry no dump valve fitted..

i sprayed some wd40 down it last night which has helped but am finding on the odd ocasion at lights it runs on 3. sometimes when driving along in any gear it could be running on 4 then 3 some i have to give it some gas which sorts it out until it does it next time.

[michael tierney]

could be an inlet manifold gasket!!

[Harrison01]

Just wondered of its possible that im getting weak spark from the aei unit. Engine has been rebuilt so it has all new gaskets

[HULK]

Have you done the suck test??:cooter:

[Harrison01]

Explain mr hulk

[HULK]

suck the vacuum pipe that goes to the aei, if everything is normal you should be able to hold a vacuum in the pipe, if you can constantly keep sucking like a whore the aei is fecked, and is the cause of your poor running issues, simples

[Harrison01]

ok lovely, will try that today.

also gonna change the ignition coil from another aei i have that is shagged...

[Jimmy_GTT]

I'd also try a compression test.

[Harrison01]

right, ive tried the 'suck' test and that is ok, cleaned and checked the gaps on the spark plugs and all ok, ive also changed the ignition coil but has made no difference...

[HULK]

Hmmm we need to try something else. Double check there's no splits in the breather pipes and vacuum pipes and I mean a GOOD look. Take them out the engine bay and inspect properly. Make sure tdc sensor wire hasn't melted either. Try a brand new mixture screw too or check it hasn't snapped

[markey b]

silly question, but is the rubber 'o' ring on the idle jet ok?

i was plagued for weeks with similar problem, swapped idle jet with another carb i have an realised there is a seal on it... strangely enough it cured my problem!

[Harrison01]

Just an update,

Problem was found to be a faulty carb, the vacum of the engine was pulling too much fuel into the engine therefore flooding it on idle, carb was stripped and cleaned several times to try and cure the problem but to no avail. i was then able to get hold of another working that i bought and it cured all my problems..

Thanks to markey mark for looking at my carb and finding the problem.
Thanks to scratcher for letting me try his carb even tho i didnt wanna give it back, and
Pres06 for selling me a working carb

[Brigsy]

Vacuum pulling in too much fuel:confused: was the aux venturi loose?

[Nick k]

I had a carb like that too afew years back, Cleaned it several times, Would run fine afterwards, soon as i came on boost it blocked up. Did my rack in.

It went to the big 'B' in the sky,

Yea in the bin... :D Problem solved.