AE95 hunting for idle

[PrettyCoolWagon]

Hi I've got a 1st gen 4afe in my AE95 wagon.

Some months back it was intermittently losing power causing instant power drop then driving along fine again.. There was no rhyme or reason to when it happened.

After taking it to 3 mechanics, & replacing the distributor myself, it turned out to be a simple lead problem.

At first all leads tested fine, only one of them was sometimes weak, only showing up occasionally when put under load.

So I got the leads replaced no probs.

Then a few weeks later it started idling rough & conking out.

I simply adjusted the screw at the end of the throttle cable so the engine idled a bit higher.

It still hunts for idle but only mildly.

Runs at top speeds fine.


I'll be buying another one of these wagons, an SR5 version for a GZE engine conversion..

http://www.toymods.org.au/forums/showthread.php?t=63842

http://www.toymods.org.au/forums/showthread.php?t=64613

...but I'm looking to get this one tidied up & running well for re-sale to re-coup some dollars.
I'm a noob but recently successfully did the timing belt & would like to know where to start, what to look for when a stock standard engine hunts for idle?

My first guess would be a dizzy adjustment using a timing light???
..but I've never adjusted a dizzy or used a timing light before...

(I'm sure any info you provide will also help me with the conversion in the near future.)

Thanks

[banana_socks]

Does it continually surge up and down revs? If so, that generally means a vacuum leak. Had the exact same thing on mine recently, plugged a leak and everything went stable.

Also does it happen whilst warming up, on only when at temp? The cold idle valve can also be problematic, causing changing idle speeds.

[PrettyCoolWagon]

Yes it does - mildly...

So I guess I get some kind of spray?? ..to spray around the air intake, plenum & runners to try & find where it's sucking in air?? (I saw a friend do this once)
Any suggestions what kind of spray?

It happens constantly, whether it's just been started or warmed up ...doesn't matter - same thing happens.

What/where is the cold idle valve?

(I'll look it up)

Thanks

[banana_socks]

First off I'd just do a physical check of all your vacuum hoses. Take them off one at a time, check the hose is in good condition without any cracks, clean up the ends they connect to, and make sure the clamps are on properly. In most cases the problem is with the hoses, but it could also be a cracked manifold or perished gasket. I think carby cleaner can be used, or use detergent to make a bunch of soap bubbles and see where they are sucked in.

I was thinking 4AGE, not FE, so unsure whether they have the cold idle valve. Its located under the throttle body, and uses the coolant to melt a wax pellet that lowers the idle after its at temp. They can have issues, such as air in the coolant causing it to solidify and melt constantly.

[PrettyCoolWagon]

Cool you've given me a few things to work & & to research - cheers

[troysota]

In years gone by these all had a problem with inlet manifold gaskets.
Check that point for a leak if you cant find anything obvious.

[Casey-G]

So plugs/vac leaks and all the other simple shit is checked out all good?

next Q is all sensors are in check/all good, timing set accordingly ect..?