4ac Idling Issue

[Corz3]

Hey guys,

 

I'm having a few problems with my 4AC. I have set the idle to 850rpm when warm and if idles perfectly. Occasionally the idle dips down to 500-600rpm then stalls if no accelerator is applied, what could cause that? Also if the idle dips to 500-600rpm if I try to hold it at 1k it'll go to 1k then just drop down again, to get it to idle normally I got too rev it out to about 5k then it'll idle normally until it decides to play up again which can be 2-4 idles later.

 

Thanks.

[slapper]

look for air leaks - that's what caused dodgey idle like this on mine.

 

cheers,

Slap

[ke70dave]

id be getting a can of carby cleaner, and spraying the crap out of the carby.

 

start the car up (with airfilter out so you can see down the throat of your carby), put your hand on the accelerator on the carby, and go nuts with the carby cleaner, spraying it into your carby.. you will need to keep the engine going with the accelerator, as the carby cleaner will tend to stall the engine. keep going with the cleaner untill the inside of your carby is shiny shiny!

 

then after you have done that see how it goes then.

 

also don't be afraid to rev the guts out of it, just make sure it is warmed up before you do this.

Edited June 22, 2010 by ke70dave

[Izak]

  ke70dave said:

id be getting a can of carby cleaner, and spraying the crap out of the carby.

 

start the car up (with airfilter out so you can see down the throat of your carby), put your hand on the accelerator on the carby, and go nuts with the carby cleaner, spraying it into your carby.. you will need to keep the engine going with the accelerator, as the carby cleaner will tend to stall the engine. keep going with the cleaner untill the inside of your carby is shiny shiny!

 

then after you have done that see how it goes then.

 

also don't be afraid to rev the guts out of it, just make sure it is warmed up before you do this.

i got exactly the same problem specially when i start it to wont start then i pump the gas abit then start it and it goes then would idle out and stall if i don't rev it would you be able to get carby cleaner from supercheap? how much?

[ke70dave]

about $12 for a can of the cleaner from supercheap. sometimes hard to find, but its usually hidden somewhere.

 

becareful as it is nasty stuff, don't breath any of it in! but it cleans stuff REAL good.

[Corz3]

Alright, I checked for air leaks and don't have any.

 

Tried the carby cleaner, that didnt work, though made it run alot smoother.

 

I'm thinking it has something to do with vacuum but can't see any problems with it....

[Suziefox73]

Maybe blocked fuel jets in the carb? Or low pressure from the fuel pump? Vac leak would be constant and you'd hear it but not always, sounds like a fuel supply prop to me!

[Murd 55]

or a dodge idle spring on the carby or something else alike. could be alot of things

[Corz3]

its only happened since i changed the engine, i just rev it out to 4k when it does it now and that fixes it temporarily ;) people look at me funny on the way to work lol

[71 Wagon]

  Corz3 said:

its only happened since i changed the engine, i just rev it out to 4k when it does it now and that fixes it temporarily :P people look at me funny on the way to work lol

 

Hi,

 

I believe this is a common 4ac problem as I have the same. Take a look at where the temp is when this happens, if it';s anything like mine it will be when you come to a stop and you are idling, thats when she'll start to warm up and the thermostat will open and the little banger starts to struggle. The only time I have had it to when it doesn't do this is when I have had new plugs, rotor button, points, clean oil and it tuned perfectly. I also have a thermofan conversion and helped but didn't solve it.

 

Hope this helps.

[ae174agze]

what i'd start by doing is

take the aircleaner off and just really quickly choke the engine with your palm while running it'll stall out a little then rev up slighly this might suck the shit from the jets if there's any

 

or when mine was doing this it could also be the idle control solenoid listen for clicking around the carbie

 

see how you go