T350 Tamora Idle Speed Control Problem - Hunting

[craigcaf]

After a 100 mile run, in stop start traffic the idle speed on my 2005 T350 started hunting quite badly with a regular swing between almost stalling and 1000rpm. Off idle no problems. All temps fine and no warning codes. Did it with aircon on or off.

Presumably with individual port throttles there is a different system fir idle speed regulation than a conventional throttle body air bypass and regulating solenoid?

Anyone else had a similar problem in tge past and can suggest the likely culprit?

Thanks.

[Tom The Cat]

Hi Craig

I think ist controlled via the ECU , which has a left and a right Trottle POT.

Looking on the Intake ...
i think the left 3 port throttles have a "blue colorerd Pot."
and i think the right 3 port throttles have a "white colorerd Pot."
Maybe reverse!

The main thing is, you have to download the Speed Six Diag Software ...
after connecting .... i think you can reset the Pot's ,
(the Value of the Pot's),ofcourse
which means, the now are the internal values in the ECU of the Pot's ...... well, after that the should be "0"!
And after this little operation , the Pot should resetet.

But,check before leaks around the Intake.
Cheers tom

[craigcaf]

Thanks Tom that makes sense. Do you know the best place to by the interface lead to connect the diagnostic port presumably to a USB port on a laptop? Then I can get access to tge ECU after downloading the software.

Thanks Craig

[craigcaf]

Thanks Tom that makes sense. Do you know the best place to by the interface lead to connect the diagnostic port presumably to a USB port on a laptop? Then I can get access to tge ECU after downloading the software.

Thanks Craig

[Tom The Cat]

Hi Craig

hane a look at this Link:
http://www.thetvrsite.com/cerbera/ecu-diagnostic-s...

There you'll find instructions to handle the software ....
Wiring to ECU and Laptop and so on ...
and ofcourse the software itself ....
let me know , if you need some help...
Cheers Tom

[mickthefish]

Hi
Had this with the tam, only happened when left standing for six or seven hours after a run
Would start ok and not be hunting but after 3 or 4 miles would hunt like mad, if I stopped and let it idle for a few minuets things would settle down and I would not have a problem.
Made the mistake of adjusting the cold idle myself as I was also having issues when cold starting BIG MISTAKE put everything out was running like a bag of sh-t, took it into Hilton and Moss they put it on the lap top and re set the pots and air flow etc, starts on cold now with no issues and have not had a repeat of the idle hunt.
If you have not had experience in setting things yourself get it done by someone that knows what they are doing you will not regret it.

Mick

[craigcaf]

Thanks guys. Just ordered the cable and will give it a go.