1.9dg Auto - idle speed too fast when in neutral or park.

[djswain1]

1987 1.9dg automatic with pierburg 2E carb

Only had the van a couple of months it has been off the road a couple of years and was undriveable due to the carb/choke setup.
I have stripped and cleaned the carb replaced all the diaphragms & gaskets, checked choke operation & replaced the vacuum pull down which gave up the ghost.
It now coldstarts Ok and drives ok. The strange thing is that when the engine is warmed up out of gear in park or neutral the idle speed is very high (I'm guessing at 1500 +) and it goes into gear with quite a clunk, once in gear (drive or reverse) the idle speed is correct.
I'm led to believe that auto models have a different carb but do not know what the differences are. I know the engine has been re-conned or replaced in the past do so no idea if it has the original carb.

[djswain1]

Anyone got any ideas on this? Thanks.
The carburettor number is 025129 015 J
Which according to this link is the correct carb
http://www.realoem.me/search/tvn/025129015J

[djswain1]

Any thoughts folks?

[kevtherev]

Ok
So have you looked at the idle speed cam once the engine is warm?
Is the fast idle throttle stop on the last step?

I think we need to establish if the basic mechanical function of the fast idle mechanism is working
If it is I then we can look elswhere

[300CE]

Have you tried adjusting the tickover when in neutral and up to temp? I'm wondering where you have refurbed the carb, it's now running better so needs adjustment to take this into account.

[djswain1]

Thanks for the replies, I'll try and take a look tomorrow and double check if it is on the last step of the cam and connect up my automotive multimeter to yes as a tacho to see what speed its u doing at hot/cold

[123-jn]

If it is on the last step of the cam where it should be try pulling the throttle lever onto it's stop because there is a solid bar running from this to the lever on the gearbox and this can get gunged up and stop the carb lever going right back to it's tick over stop. The return spring can also become a bit tired. You could try an extra light spring to help the spring on the carb if this is the case.

[djswain1]

I think the problem may just be down to engine wear & lack of power. I suspected the engines best years were behind it as it was burning (& leaking oil). Today I ran it for the first time with the plastic air inlet housing removed from the top of the carb and the engine is breathing really heavily.
When up to temperature the high idle adjuster is on the last step of the cam and the throttle linkage to the gearbox is returning correctly. The idle speed needs to be about 2000rpm in neutral to prevent stalling when in drive or reverse with the engine cooling fan cutting in. When drive is engaged the idle speed drops from around 2000rpm to around 900rpm. If the idle speed is set any lower it will stall when in drive or reverse (foot break or hand brake on) when the cooling fan cuts in replicating stop start driving.

[kevtherev]

Right.
So the engine stalls if the idle speed is set to 900 rpm?

So do you have a tacho to see this?

If the engine stalls getting in gear then two things spring to mind
Timing and the gearbox.

[djswain1]

I'm using the tacho function on my automotive multimeter.
If you set the idle speed in neutral or park about 2000rpm when hot it will drop to about 900rpm when drive or reverse is engaged if the idle speed is lower it will stall when drive or reverse are engaged. All the time the engine is in gear it will drive fine and idle fine. No noises or unexpected behaviour from the gearbox. I've changed the gearbox oil and strainer which made no difference and no nastys found in the sump.
Timing is the next thing I want to check but the amount of smoke coming from the crankcase breather is not a good sign and I think a rebuild is on the cards.

[ajsimmo]

Torque converter stall speed sounds wrong. Are you using correct atf?

Sent from my GT-I9305 using Tapatalk

[kevtherev]

The "smoke" maybe just oil mist from the case, if the mist trap is shagged, and they usually are, it's not a problem anyway.
Only a compression check will condemn an engine, not guesswork.

[djswain1]

If I get time at the weekend I'll take off the breather tower and have a look at it now I have a new o-ring seal for it, I'll also try and check the timing and compression if I can find my petrol engine compression tester.

[djswain1]

Torque converter stall speed sounds wrong. Are you using correct atf?

Sent from my GT-I9305 using Tapatalk

I changed it (not a full flush) which made no difference I used Carlube ATF-Q3
http://www.carlube.co.uk/transmission-f ... sion-fluid
Haynes Manual & ownets manusl just says Dexron

[kevtherev]

I'm sure you can understand remote diagnosis is at best difficult
That said my money is on timing or an air leak into the induction side