The Dispatch | Expert | Scudo Hub

Dr_Evil_01

Member

Registered: 2016-09-20

Posts: 6

Engine Idle Problem

Hi All,

I have two Expert Vans, one is a 1999 1.9D (Non Turbo) and the other is the 2003 1.9D (Non Turbo).

The 1999 van runs like it should even with 182K on the clock.

Unfortunately, I cant say the same for the 2003 one... Every time the van is in neutral or the clutch pedal is pressed down, the engine doesn't sit at idle. It climbs through the rev range until it hits the limiter.
Upon closer inspection I noticed the idle screw was screwed all the way in, therefore pushing the throttle arm around. I reset this to a position where it barely pushes the arm off its resting position. But still the engine revs up. Once the van is in gear I can pull away without touching the throttle. Once moving the van drives like it should, although every gear change and sitting at junctions / traffic lights can be a little noisy and slightly embarrassing.

I have removed what I believe to be the Throttle Positioning Sensor (TPS), cleaned it, checked it works and refitted it but to no prevail.

Also checked every fuse in both compartments.

All external moving parts of the throttle assembly (Cables & Levers) move freely as they should.

Any help or advice will be gratefully received.

Thanks

Dr E

Last edited by Dr_Evil_01 (2016-09-20 11:56:49)

Casper

Member

From: East Lothian

Registered: 2015-12-20

Posts: 2,180

Re: Engine Idle Problem

Not 100% sure exactly how a diesel gets its air/diesel then mix but if a petrol i would say air leak and after the air filter.

monkeynut

Member

From: oop north

Registered: 2014-07-11

Posts: 174

Re: Engine Idle Problem

Has it been like this since you have had it?  As casper said could be a air intake problem   or somone has been messing with the fuel metering  screw (that govens the amount of fuel entering the engine )
A disel sucksits own air and mixs in the cylinders  in you have only control over the fuel to the injectors
Bit of extra info
Black smoke = over fueling  but burning it  White=unburnt fuel  usualy caused by fuel condencing in the cylinders on cold morning startups   .

Dr_Evil_01

Member

Registered: 2016-09-20

Posts: 6

Re: Engine Idle Problem

Has it been like this since you have had it?  As casper said could be a air intake problem   or somone has been messing with the fuel metering  screw (that govens the amount of fuel entering the engine )
A disel sucksits own air and mixs in the cylinders  in you have only control over the fuel to the injectors
Bit of extra info
Black smoke = over fueling  but burning it  White=unburnt fuel  usualy caused by fuel condencing in the cylinders on cold morning startups   .

Hi Monkeynut & Casper,
Thank you for your replies. No it doesn't smoke to an extent that either of the above is noticable. Where is said Fuel Metering Screw located? What should the correct setting be for this screw?

I have checked every hose / pipe for an air leak and haven't found any splits, loose connections, etc.

I have noticed that the diesel return pipes on the injectors have started to weep, so will hopefully get round to replacing these soon.

A friend mentioned that it could be the high pressure fuel pump (believed to be pictured). I mentioned that the previous owner said that some swarf might of fallen into it whilst they were drilling out a broken bolt... not sure how true this is. But, my friend said that the shafts or something could be scored, hence letting more fuel through than required.??

Not sure, I'm no mechanic.

Cheers

Dr E

monkeynut

Member

From: oop north

Registered: 2014-07-11

Posts: 174

Re: Engine Idle Problem

if not smoking it will proberly be the fuel scew setting,  is the throttle cable slack to the toutch? it could be as simple as i tight throttle cable   ,back of idle screws slacken the cable and see if you can push the lever back to cut the revs,, cant be of more help unless i get my hands on it

Dr_Evil_01

Member

Registered: 2016-09-20

Posts: 6

Re: Engine Idle Problem

Hi Monkeynut,
Yes, the cable has a certain amount of play before moving the throttle arm. The engine seems to rev at the last position the pedal was at during gear changes. So I had already checked the cable.

Does it have a potentiometer fitted to the throttle assembly or somewhere along the line between the pedal and the fuel pump?

Do you have a diagram of where the Fuel Metering Screw located?

Thanks

Dr E

Last edited by Dr_Evil_01 (2016-09-28 13:28:29)

monkeynut

Member

From: oop north

Registered: 2014-07-11

Posts: 174

Re: Engine Idle Problem

have a look in the manual i put up in downloads  it should cover the later ones too as they did have some electronic gubbings on them(it has diagrams of the lucas pumps ( im more of a bosh man workrd alot with them on my vws)

Casper

Member

From: East Lothian

Registered: 2015-12-20

Posts: 2,180

Re: Engine Idle Problem

If you can be bothered before the cold weather sets in start to swap things over with the good van and when the good van starts to run like crap then you know what part you want to fix/replace. Cheaper than the mechanic.

Dr_Evil_01

Member

Registered: 2016-09-20

Posts: 6

Re: Engine Idle Problem

Hi Casper,
As much as I would love to be able to do this I don't have the time, the skills or the equipment to do so.
Plus I am looking to sell the older of the two vans.

Hi Monkeynut,
I have downloaded the manual and will attempt to find what I am looking for. If not its going to be an expensive visit to the garage I think..!!

Cheers

Dr E

monkeynut

Member

From: oop north

Registered: 2014-07-11

Posts: 174

Re: Engine Idle Problem

I take it you have tried backing  off the throttle stop ? if you are local to preston i would have a look for you

Dr_Evil_01

Member

Registered: 2016-09-20

Posts: 6

Re: Engine Idle Problem

Hi Monkeynut,
Yes backed it right off. Going to stop off at a garage on the way home.
I'm in the west county, so Preston is a hit of a journey for me. Unless you're referring to the Preston area of Paignton ?

How it is now set

Last edited by Dr_Evil_01 (2016-10-07 16:36:46)

TeddyMcB

Member

Registered: 2022-11-21

Posts: 15

Re: Engine Idle Problem

The voltage of 2.61 on yellow tab  in the picture above, it this what the out put (center wire) should be on the potentiometer when the engine it ticking over?

TeddyMcB

Member

Registered: 2022-11-21

Posts: 15

Re: Engine Idle Problem

To clarify what position is the accelerator peddle at when you set/read 2.61 Volts on the out put of the potentiometer which is the 3 wire component directly above the yellow tab?