Tdi 300 idle speed

**big guy** · 22nd April 2009, 05:52 PM

Hi guys

I have recently had my new (to me) Disco serviced and intercooler upgrade done with the tweaking.
Car now plumes and uses more fuel which they told me would not happen.
Oh well.
My idle is also at almost 900rpm, the question is, where is the idle adjustment?

I have already been back to mechanic which is by the way very very reputable here in SA. They said that my fuel filter was not changed because the mechanic thought it looked fine.
I went home and thought about that and came up with "What a load of crock".

They forgot several other things also like new hose clamps because I had all hoses and timing belt changed and on way home my low coolant alarm went crazy.

I will never use that lot again but for parts as they have everything.

I emailed to see if they can look at idle and the like but they have not returned my e-mail.

Anyhow, car goes good, very good just smoky.

Back to the idle and can I get some help on how to put back to normal which I believe is around 750rpm.

Thanks and have a great day

**Blknight.aus** · 22nd April 2009, 07:40 PM

I aim for 650ish as a start point and then once the engines running and warmed up I'll adjust it to 50 RPMish higher than its minimum smooth idle.

on a really good tdi that can be as low as 500rpm.

Ive had the 2.25's idling at 450, just.

**Jojo** · 22nd April 2009, 07:54 PM

Do you have an electronic injection pump or the mechanical one. on the latter, there is a (well protected) screw you will have to adjust counterclockwise to slow down idle speed and turn clockwise to increase (or was it vice versa???

). Sorry I don't know about the electronical version.

Cheers

**big guy** · 22nd April 2009, 08:27 PM

Thanks guys

I just don't know where this elusive screw is located.

I sit at the lights and have to turn radio up its that loud.

i think they stuffed my tappets yoo.

**justinc** · 22nd April 2009, 08:53 PM

The extra smoke (Depending on HOW much extra...) is not uncommon with a tweak, and the idle speed WILL change if the main fuel screw was adjusted. You will find that IF you drop the idle back, it may hunt a little when in drive if it is an auto. The tweaking I hope was done with a pyrometer because at that level of change in performance and especially the extra fuel consumption, I would be worried about EGT's. The extra engine noise could be that the timing is now a lot more advanced. Possibly too much? Hopefully the valves are set properly, if the performance is good I'd say the clearances are OK.

The fuel filter bothers me, unless it WAS removed and emptied into a container to inspect it, but they are cheap enough to fit a new one.

JC

**dullbird** · 22nd April 2009, 09:01 PM

think mine normally idles at 750.....and hunts ever so slightly when stopped at the lights or in traffic..but only when in gear

**justinc** · 22nd April 2009, 09:10 PM

Another point, probably irellavent in Big Guys' case, but having a new alternator fitted with a different diameter pulley will throw the Tach readings out by as much as 150rpm.

DB, has your Tdi been tweaked?

JC

**dullbird** · 22nd April 2009, 09:15 PM

No not to my knowledge it still had the collar on it up until recently when ian broke it off.....I did want to adjust the pump but not gotten around to it

**justinc** · 22nd April 2009, 09:32 PM

I was wondering only because the 'hunting' in drive is usually noticeable after some main fuel screw tampering. BTW, when were the valve clearances last done? that also makes a difference to idle quality/ smoothness. Again, made really only noticeable with an auto behind the Tdi.

JC

**dullbird** · 22nd April 2009, 09:50 PM

probably never how do you do that and how much does it cost? is it an issue if its not done....does the head have to be removed to do it?

Thread: Tdi 300 idle speed

Thread Tools

Tdi 300 idle speed

Bookmarks

Bookmarks

Posting Permissions