Ae-82 4ac Rough Idle / Stall Out After Long Runs..help?

[montryrommel]

Hi Guys

I need some help / advice if you can. Cheers

 

I have a strange problem with a 1986 CS-X sedan.

200K+, 4AC, AE82, three speed auto.

 

This car is in pretty good nick, both inside and out.

The geezer I got it from had just replaced a bunch of bit and pieces.

Dizzy cap, tires, all filters, timing belt, heaps of vac lines etc.

I just put a fresh battery in as well.

 

It runs really well around town.

I have it idling at 750rpm when in drive (and auto choke is off)...hopefully that's not too low.

 

So here is the problem.

I drove it 100km out of town.

All good on the way out.

However, on the way home, the first time I had to slow down for a light it ran really rough and the idle rpm dropped down to stalling point (around 400rpm).

It was a real nightmare to get home, dropping it into neutral and pumping the gas to keep it from stalling out every time I had to stop in traffic.

It was not running any hotter than normal.

 

Next day, it was back to normal. Started up sweet as, drove around town no worries.

 

I have cleaned the EGR, which had some water in it (I think from the last owner high pressure spraying the engine bay before he sold it) and my mate who knows far

more than I do about cars had at the carby with carb cleaner.

Nothing obvious there.

Ran fine.

 

Went out on the open road to test it...and exactly the same thing happened.

On the way home, after 70km of 100km/h driving...the first stop at a light had the revs dropping until it wanted to stall.

But it didn't happen on the way out of town?

Weird eh?

 

Sorry for the long explanation...it's hard to write less without leaving out info I guess.

 

So...any help would be appreciated.

I have had people mention the float and also the coil as potential things to check.

I am not good enough with mechanics and don't have the tools to take the carby apart to check the float.

I keep hearing that these rollas all have issues with the carbys?

Is that true.

If that's the case, wouldn't it be risky just trying to get another carby...just running into the same / slightly different problems?

 

It's a great wee car. If I can get this problem sorted, I'm onto a winner I rekon.

Cheers for any help you can throw my way.

[jex]

Hi Guys

I need some help / advice if you can. Cheers

 

I have a strange problem with a 1986 CS-X sedan.

200K+, 4AC, AE82, three speed auto.

 

This car is in pretty good nick, both inside and out.

The geezer I got it from had just replaced a bunch of bit and pieces.

Dizzy cap, tires, all filters, timing belt, heaps of vac lines etc.

I just put a fresh battery in as well.

 

It runs really well around town.

I have it idling at 750rpm when in drive (and auto choke is off)...hopefully that's not too low.

 

So here is the problem.

I drove it 100km out of town.

All good on the way out.

However, on the way home, the first time I had to slow down for a light it ran really rough and the idle rpm dropped down to stalling point (around 400rpm).

It was a real nightmare to get home, dropping it into neutral and pumping the gas to keep it from stalling out every time I had to stop in traffic.

It was not running any hotter than normal.

 

Next day, it was back to normal. Started up sweet as, drove around town no worries.

 

I have cleaned the EGR, which had some water in it (I think from the last owner high pressure spraying the engine bay before he sold it) and my mate who knows far

more than I do about cars had at the carby with carb cleaner.

Nothing obvious there.

Ran fine.

 

Went out on the open road to test it...and exactly the same thing happened.

On the way home, after 70km of 100km/h driving...the first stop at a light had the revs dropping until it wanted to stall.

But it didn't happen on the way out of town?

Weird eh?

 

Sorry for the long explanation...it's hard to write less without leaving out info I guess.

 

So...any help would be appreciated.

I have had people mention the float and also the coil as potential things to check.

I am not good enough with mechanics and don't have the tools to take the carby apart to check the float.

I keep hearing that these rollas all have issues with the carbys?

Is that true.

If that's the case, wouldn't it be risky just trying to get another carby...just running into the same / slightly different problems?

 

It's a great wee car. If I can get this problem sorted, I'm onto a winner I rekon.

Cheers for any help you can throw my way.

[jex]

Is there n intermittent fuel starvation?

Maybe one of those "numerous" vacuum lines is spilt or not sealing ,

esp: the one from the flange on the front of the carby, attched to the servo on the air filter?

[montryrommel]

Is there n intermittent fuel starvation?

Maybe one of those "numerous" vacuum lines is spilt or not sealing ,

esp: the one from the flange on the front of the carby, attched to the servo on the air filter?

 

HI Thanks for the ideas.

The vac lines are all good as far as I can tell.

It seems to be a problem with the fuel running rich rather than being starved.

 

It's a strange one, and hard to test as I have to run the car for at least 1/2 an hour (or even longer!) on the open road before the problem exhibits itself.

Around town it behaves perfectly.

 

Cheers

Edited August 25, 2008 by montryrommel

[KE70-from-mt-panorama]

Hey Mate. Do these have a points dizzy still? or did the change to electric in these models? If its points it may just be the points have burned out. When the points went in my old ke it produced very similar symptoms.

[montryrommel]

Hey Mate. Do these have a points dizzy still? or did the change to electric in these models? If its points it may just be the points have burned out. When the points went in my old ke it produced very similar symptoms.

 

Hi

Thanks for the info.

Not sure whether it's points or electric.

My mate who's helping me said we'll have to have a look next time he's over.

He doubts that it's a points dizzy.

 

A question...if the points are burned out, would it not be a problem all the time...not just after 1/2 hour+ of open road driving?

 

Cheers for your help.

[Trev]

Hi

Thanks for the info.

Not sure whether it's points or electric.

My mate who's helping me said we'll have to have a look next time he's over.

He doubts that it's a points dizzy.

 

A question...if the points are burned out, would it not be a problem all the time...not just after 1/2 hour+ of open road driving?

 

Cheers for your help.

 

Its an AE82, It will have an electronic dizzy.

[montryrommel]

Its an AE82, It will have an electronic dizzy.

 

Thanks for the info.

Electronic points it is.

 

So...not burnt out points then...any ideas?

 

Cheers

[towe001]

To me it sounds like a fuel starvation problem.

And if its what i'm thinking when it happens again see if you shut the motor off and check the filter, see if its got any fuel in it. Cause to me it sounds like you've got a build up of crap in the tank. A similar problem happened to a mates old hi-lux. Not only was he getting to be a real expert on the carby but was starting to get "off" on the fumes. Till my dad turned around and told him to drop the tank and clean the sh&t out of the tank. The amount of crap in the tank was blocking up the up-take pipe. Wouldn't happen all the time but when it did it caused similar problems.

 

If i remember correctly there's a sight glass on the carby. Check that if there's fuel in the filter. If its low your problem would be the float and/or the needle sticking.

The idle-up valve could be sticking. Helps in bringing the idle back up when the motors at temp. Could be another thing to follow up on

 

As a side note the idle should be around 850 or so being an auto. About 100rpm higher then a manual.

[montryrommel]

To me it sounds like a fuel starvation problem.

And if its what i'm thinking when it happens again see if you shut the motor off and check the filter, see if its got any fuel in it. Cause to me it sounds like you've got a build up of crap in the tank. A similar problem happened to a mates old hi-lux. Not only was he getting to be a real expert on the carby but was starting to get "off" on the fumes. Till my dad turned around and told him to drop the tank and clean the sh&t out of the tank. The amount of crap in the tank was blocking up the up-take pipe. Wouldn't happen all the time but when it did it caused similar problems.

 

If i remember correctly there's a sight glass on the carby. Check that if there's fuel in the filter. If its low your problem would be the float and/or the needle sticking.

The idle-up valve could be sticking. Helps in bringing the idle back up when the motors at temp. Could be another thing to follow up on

 

As a side note the idle should be around 850 or so being an auto. About 100rpm higher then a manual.

 

Hi Towe001

 

Thanks for the info. Very helpful.

It's been running rough from cold start now, not just after a long drive.

Also doing a strange 'surge' when stopping after a drive. It 'blips' up 200 rpm in a regular pulse.

Very odd.

 

When it is actually driving...it behaves beautifully.

 

I will look into getting the gas tank flushed asap.

 

Cheers

[towe001]

I think i'd be seeing about a compression test first. If that comes back negtive have a poke around the intake manifold and carby for air leaks