Help please! GQ 2.8 cold idle too slow.

Hey all, can anyone give me some leads as to why on cold startup my truck fires beautifully but then idles at 450rpm and feels like its about to stall (normal idle is 650 - 750)?

I have turned up the idle screw but it only makes a difference when warm and it idles and drives perfect when warm.

Is there a temperature sensor or something that should up the idle when the engine is cold?

Truck fires up perfectly with a tiny puff of black. Oil sensor tells me cold idle pressure is at 80psi which drops back to 20psi when engine is warm.

Any ideas appreciated! Thanks

a seal in the pump is gone. to check which seal is gone you need the put your hand at the back underneith the pump If it wet the rear seal is gone ( or there are drip marks on the front diff pumpkin. if it is dry an internal seal has gone. nothing you can do it gunna cost you

Cheers
Benny

Thanks Ben-e-boy. You sound very confident the pump is the problem - experienced the same thing yourself?

Having just spent $3,000 on a pump rebuild I was hoping this wasn't going to be the problem but I did have a bad feeling about it. There's no wetness so I guess it's internal.

At least the repairs are under warranty but man its hard to find good help these days!

Cheers, Lachie

Yeah mate I have had a rear seal go and a mate had the exactly the same problem as you and it was an internal seal.

Appreciate the advice. Thanks mate.