Over revving and other issues

[Chris P]

It sounds like you are zeroing in on the problem Tris...good luck. (its all bit techy for me)

I am fortunate enough to live near Richard Hutchinson who has sorted out the occasional problem of a similar nature.

[Guinney1971]

Good luck Tris, I'm sure you'll crack it soon.

[Rissy]

(11 Nov 2018, 13:22)TristanC Wrote: I’ve carried out more diagnostics.....

Thermistor is good. I tested resistance and showed it was fine cold and hot.

I took the idle motor out of the system completely and blanked the hoses.
This way I could set the idle via the screw on the throttle.
The idle stop screw wasn’t even touching the plate.... so I screwed it in to increase throttle.

She started up and I further adjusted the screw to get the idle around 800-900 rpm.
And there she stayed! Even when warm!

So this tells me that something is opening the idle motor as the engine warms.
Or is the idle motor installed the wrong way?
(I installed it with the arrow pointing to the rear) so I reversed it to point to the cabin and restarted he car.

Guess what? The idle was stable! What the heck?
Idle motor pointing the wrong way and the idle stays low? (1,000 rpm)

So now the idle settles at 1,000 rpm at all temps when the idle motor is the wrong way.

So that’s it for now. I’m going to reinstall the motor the correct way to see if the fiddling with the idle stop screw has helped anything.

The arrow of on the idle speed regulator signifies the correct flow of air direction through the valve, and in the case of our interest, the air flow goes through the idle speed regulator from the carbon canister and through the CSI body and then in towards the air induction body through the "pipe of pain". So the arrow should be pointed towards the "pipe of pain" (towards the cabin of the car).

The air is in essence sucked through all this lot from the carbon canister due to the vacuum build up in the induction body when cranking and running the engine because of the pistons being driven up and down (engine exhaust stroke). The regulator controls the amount of air that can be sucked into the body outside of the main venturi port intake under your air filter housing.

[TristanC]

Cheers Rissy!

Therefore my issue since installing the new idle motor is that it was the wrong way!!
Doh!!
(I honestly thought the arrow was to point to the rear)

Well, in that case, she’s sorted!

[Chris Williams]

Fingers crossed !

[Nick H]

Sounds like you have tracked down the problem.
Fingers crossed as Chris said

Nick H

[TristanC]

Tax is up end of the month.... so she’ll be hibernating while the roads are salty.
If a good clean day appears between now and then, I’ll take her out and report back.

Maybe then I can conclude this epic thread with a summary for someone’s future use/amusement

[TristanC]

I took 11477 out for a run today (dropped off my daughter to her drama group, then off to see Mum)

And she performed brilliantly! Idle was spot on!
So I am very pleased indeed.

And the issue from the outset was indeed a dodgy original idle motor.
Which in turn blew my idle ECU.

I now have an upgraded idle ECU and an idle motor from Germany, via eBay.

And then the persisting high idle was due to having the idle motor the wrong way!

For anyone reading hoping for a resolution to their similar issue, the idle motors orientation requires that the directional arrow points toward the cabin.
(This is despite my original pointing toward the rear of the car and indeed directions for install on some sites suggesting that the arrow is to point to the rear)

So there you go! Sorted!!!

[Chris P]

Good for you Tris.....I'm just re-assembling my 'Vally of Death"...I hope I Get all the stuff connected OK!

[TristanC]

Thanks Chris,
You’ll be fine - you’re more seasoned with D’s than I and you have some knowledgable bods on your doorstep up there in Derby!

[Nick H]

Nice one Tris!
You have come across the problem with putting things back as you find them. Chances are someone was in there before.
I had that with the fuel pump pickup orientation. Watched Martin’s video and then it all became clear that it had been installed incorrectly.

[Chris P]

I remember a club member who imported a car and it didn't run very well.....We found the fuel feed and return pipes were swapped over! It still ran, but not very well!

[TristanC]

It was very odd.... the original was installed the other way and the car ran fine.

Oh well I’m happy it’s running so well again.