4A-Ge Idle Problems

[langdon69]

Hi all, just wondering if someone can help me out, first of all I did do a search but couldn't find an answer to my specific question but I apologize if i just didn't search quite the right thing. So, I have a 1989 Toyota Corolla seca sx with the 100kw 4A-ge, 270,000kms, pod filter, extractors and full 2 1/2 or 2 1/4 inch exhaust. Now my problem is that it will not idle when it's cold, ever. It will always stall until it starts to warm up, even my rather tired ke-70 with 678,000kms will start first turn and idle nicely, just wondering what I should do as I thought these cars had an idle up feature for cold starts??

[parrot]

Does it have an oxygen sensor in the exhaust?

[carbonboy]

^^^

 

Is the cold start injector hooked up?

[langdon69]

to the best of my knowledge yes it does have the oxygen sensor in the exhaust and yes the cold start injector is hooked up, don't know if this helps or means my problem will be more expensive and difficult to fix lol :laff:

[parrot]

Cold start injector only operates for a couple of seconds.

 

Can you see an oxygen sensor in your exhaust? You can't miss it really if it is there. Reason I ask is that with an aftermarket exhaust, potentially it was removed.

[langdon69]

yeah it does have one an it's hooked uo, It has genie extractors that had the thingy ( very technical term that lol :happy: ) for the sensor to bolt onto. Someone told me once that they have a wax pellet in the throttle body and that can fail over time or some such thing, or is that nonsense?

[Hiro Protagonist]

What's the idle speed like when warm?

 

There is history with the wax pellet idle-up system failing or not functioning properly, but normally it is so that the car never gets to warm idle and just sits there on ~2000rpm all the time (either because the pellet has jammed or because of an air bubble in the cooling system.

[langdon69]

Idle speed when warm is around 900-1000 rpm. Ahh well it doesn't sound like the wax pellet is my issue then :hmm:

[Hiro Protagonist]

If you want to eliminate the wax pellet as a cause then pull off the intake pipe, cover the small hole inside the throttle body and then start the engine (cold), give it a _tiny_ bit of throttle and see if the problem goes away. If it runs then then it is quite possible that the wax pellet/idle up valve is completely jammed (I think they do tend to clog with carbon/oil deposits too), in which case remove it and completely clean it and the throttle with carby cleaner.

[langdon69]

Oh cool, thanks for the info :happy: I'll try that first thing tomorrow and let you know how I go :dance: