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Over revving and other issues - Printable Version

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RE: Over revving and other issues - TristanC - 03 Oct 2018

Ooooo gadgets! I like gadgets. Especially useful ones.... Smile

But you say it would affect top end performance?
Well, I have to say, she performs without issue, accelerating through the power band with ease. Pulls phenomanly well. When she’s in motion, you wouldn’t know there was anything wrong...

Exciting news!!!!!!

I’m sooooo close to solving this!!! 
Something is sticking..... not sure what yet.... or possibly a dirty or dodgy throttle switch.....

If I push the throttle spool gently, as you would if accelerating from the pedal, the high revs are there.
Give the spool a quick flick???? The revs drop!!!!

Take a look:





RE: Over revving and other issues - Chris P - 03 Oct 2018

I think it needs a good oil and free it all off...mines the same!


RE: Over revving and other issues - TristanC - 03 Oct 2018

Quite right Chris. I was speaking to Stu earlier today and he said to wd40 it.
Which I’ve done and will return to her tomorrow.

At least I’ve narrowed it down now! Yay

(And I’ve created and EPIC 10 page thread in the process :| )


RE: Over revving and other issues - priesh - 04 Oct 2018

Hindsight is a great thing lol!

Would be great if it all came down to a quick spray of WD40


RE: Over revving and other issues - TristanC - 04 Oct 2018

Well I think there were still some issues along the way - mainly the idle motor......
When I resolve this, I’ll summarise the issues and where I went wrong.....


RE: Over revving and other issues - Rissy - 04 Oct 2018

So going back to post #15, points 1-4. Only now are these being investigated? :-D

...just saying ;-)


RE: Over revving and other issues - Chris P - 04 Oct 2018

Now now Chris.......we all live and learn ...and try and help each other by sharing our experiences.

But it can be tricky when you have loads of 'balls in the air' at one time. Undecided


RE: Over revving and other issues - Rissy - 04 Oct 2018

tongue in cheek Chris. As always. :-)


RE: Over revving and other issues - Stuart Rees - 04 Oct 2018

(04 Oct 2018, 10:38)Rissy Wrote: So going back to post #15, points 1-4.  Only now are these being investigated? :-D

...just saying ;-)

No Rissy, I checked these when I called with Tris both times, remember the AC belt has thrown rubber deposits since then and may now be causing the throttle issue. We believe the full throttle Microswitch to be faulty and giving the opposite signal it should to the injection system (i.e frequency valve) we're hoping a good lubrication of the throttle parts will do the rest...
The original idle motor was faulty as a chunk of metal fell out of it... and this is suspected to have blown the ECU. Swapping my parts resolved the problem on that day but there were other gremlins in the system which are hopefully almost sorted :p Whew

Stu


RE: Over revving and other issues - Nick H - 04 Oct 2018

Tris,
I had the same sticky throttle issue a couple of years ago.
I ended up replacing the inner cable. If you do this flush out the outer
cable with WD40. Put paper towels round the end in the footwell.
Do this before you put in the new inner cable.

Does your car have the throttle de-ice recall fitted? If not I suggest fitting it as it
helps stop water getting down the cable.

Nick H


RE: Over revving and other issues - TristanC - 04 Oct 2018

(04 Oct 2018, 10:38)Rissy Wrote: So going back to post #15, points 1-4. Only now are these being investigated? :-D

...just saying ;-)

Lol - No!! Big Grin

In fact the switch, and the throttle have always been perfectly fine and rechecked over and over.
No extra play in the throttle arm and the butterflies open and close fine as explained a few posts back.

Stu, I’ve disconnected the full throttle switch, but still no joy.

I’m wondering if the idle microswitch is faulty if the wd40 doesn’t help.

At least I’m the right area.

Once all sorted, I will summarise all the issues, because as Stu said, the idle motor was the main problem originally, then that blew the idle ecu and now as a result of flying rubber, something is gummed up....

I’ll get there


RE: Over revving and other issues - Guinney1971 - 05 Oct 2018

handy that Stu's about to give you a hand and compare/swap parts Smile


RE: Over revving and other issues - TristanC - 05 Oct 2018

Yep - we’re lucky to have a seasoned owner here in Wales. Smile


RE: Over revving and other issues - TristanC - 24 Oct 2018

Still plugging away at this. Lol

So it seems that whilst there must be something sticking..... if I allow her to idle nicely for a few minutes, the revs start to rise without any input from the throttle......
Once warm, no amount of “flicking” will drop the idle.

A few theories, perhaps you guys and gals could think about for me.....

1. Could it be a dodgy idle microswitch? (but why would it idle ok cold then high when warm?)
2. Could the thermistor be bad? Should I try a resistor on the relevant pins at the idle ecu?
(I’ve read about this, but have no idea how... guidance appreciated)
3. Could the curb idle screw at the throttle arm require adjusting?
(I can’t see how...... although I did remove the idle microswitch at one point along with the bracket holding it..... perhaps this threw out the rest position of the screw?)


RE: Over revving and other issues - TristanC - 11 Nov 2018

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.