Over revving and other issues

[Chris P]

Give my very best wishes to your dad Tris. I thought about him at 9 o'clock last night in Sheffield.

[Rissy]

(25 Sep 2018, 09:26)TristanC Wrote: Rissy:
CSV, I am unsure how long it fires for.- I’d have to check that

The CSV firing period is variable according to ambient temperature and therefore the starting temperature of the thermotime switch conductor to begin with. If it's warm enough outside, it shouldn't fire at all, but when it does, it shouldn't fire for any more than a few seconds at most. It should only also fire during cranking of the engine when starting. You can take it off and stick it in a jar and watch what it does when someone else cranks over the engine. This is also a good test to check for the injector even working in the first place.

If something is not right, and that thing is firing all the time; this could be a reason for high revs (potential flooding too - unless someone pulls back the mixture to compensate ;-) )

The fact your car revs ok when cold but too high when warm may just be a symptom of the engine temperature coming up; possibly meaning the actual issue is always there from the start.

...just another thing to check over and eliminate from your puzzle. :-)

[Chris Williams]

All good replies (even and including Chris M)   but yes you will get there, it all seems a bit odd really. But as I suggested take the A/C out for now it just does not seem right in how it's running and 'if' it's putting an extra load (and it would be a lot) then it would not help with your idling issues at all. I hope your Dad's feeling better soon.
Chris

[TristanC]

Thank you everyone for the kind wishes for Dad.

ChrisP, I will be seeing him this evening, so will remind him to you. Thank you

I’ve had 10 mins with the car just to try a few things.

Car started, but didn’t want to run. I’ve found this while I’ve been diagnosing and only richening the mixture will keep her going.
I removed the AC belt, and the idle still crept up after a few minutes.
I also them shut the car down and disconnected the cold start injector.
Restarted the car, but still the same.

What I have found is that even if the car is warm, then you close off and restart, it will idle around the 800 mark nicely...... but then creep up as she continues to idle.

While she was running with out the AC belt and cold start I dialled in the mixture using the half way point between lean and rich almost dieing.....
But that keeps the revs to 1500 or so....

Anyway..... I still have things to try from all the replies. Just wanted to get those things tried that were easy to start with.

[Stuart Rees]

Tris, I'll try to pop down again soon and help sort it. Both times, swapping a part seemed to do the trick. Swapping the idle motor brought the revs back to normal on the 1st time, then the ECU did it the 2nd. If you don't have any luck over the next few days, we'll go further into the intake/distributor. Also may be worth swapping the vacuum lines anyway incase it's a small leak that we couldn't detect.

Stu

[priesh]

Maybe just try running it with the thermotime disconnected? Assuming you haven't tried that already. Helped on mine initially before I took it down to the valley and replaced a bunch of electrical stuff

[TristanC]

I haven’t tried disconnecting the thermotime switch. I’ll have to educate myself on its position first

And Stu, thanks my friend. We will hook up on messenger to arrange another tech session.
Maybe my new idle motor is pants..... lol

I don’t believe it can be the ecu because when that went, it shot up tk 2,000rpm no matter what.
But willing to try anything.

[Chris P]

nice picture of you and your Dad Tris. 
.http://newdelorean.co.uk/wp-content/uplo...1E46C.jpeg

[priesh]

(26 Sep 2018, 21:32)TristanC Wrote: I haven’t tried disconnecting the thermotime switch. I’ll have to educate myself on its position first

And Stu, thanks my friend. We will hook up on messenger to arrange another tech session.
Maybe my new idle motor is pants..... lol

I don’t believe it can be the ecu because when that went, it shot up tk 2,000rpm no matter what.
But willing to try anything.

The thermotime is at the side of the engine closest to you, below the W pipe. Think it is gold coloured. If it is dodgy it may impact things like the CSV etc

[TristanC]

Thanks ChrisP for the pic. That’s was a great day. Great memory

And thank you Priesh. I will take a look tomorrow - I’ve seen the connector you are talking of. 

Cheers
Tris

[Rissy]

Disconnecting the thermotime switch will have the same effect as disconnecting the CSV itself. It's just a different way of preventing the CSV from firing. Pulling the plug on the CSV disconnects its firing mechanism entirely, and disconnecting the thermotime switch disconnects its ground path, which also prevents it from firing, save for a potential short of course, but i've never heard of that ever being experienced by anyone before.


However, from what Tris expanded with yesterday with his little bit of a poke around, i'm now not suspecting that at all to be the problem.

I'm suspecting ECU again, or a sticky vacuum membrane in the distributor (or the vacuum solenoid circuit which drives it) (if all the throttle body gubbins checks out ok, which as i've said already, requires a proper strip down to assess from the butterflies right through, and includes the spool etc as discussed before, above.)

[TristanC]

Is it worth disconnecting the vac line from the distributor?
(I’ve read somewhere to try this...)

If so.... any guidance on where to do it?? Lol

Thanks
Tris

[Rissy]

(27 Sep 2018, 13:51)TristanC Wrote: Is it worth disconnecting the vac line from the distributor?
(I’ve read somewhere to try this...)

If so.... any guidance on where to do it?? Lol

Thanks
Tris

Yeah that was me in POST #100.

It's on the diaphragm on the side of the distributor. Or the other end of the same line on the vacuum solenoid.

[Chris P]

Tris,

its very handy if you can get another Delorean parked along side and swap bits over and see what effect that has on each.

[priesh]

(27 Sep 2018, 08:33)Rissy Wrote: Disconnecting the thermotime switch will have the same effect as disconnecting the CSV itself. It's just a different way of preventing the CSV from firing. Pulling the plug on the CSV disconnects its firing mechanism entirely, and disconnecting the thermotime switch disconnects its ground path, which also prevents it from firing, save for a potential short of course, but i've never heard of that ever being experienced by anyone before.


However, from what Tris expanded with yesterday with his little bit of a poke around, i'm now not suspecting that at all to be the problem.

I'm suspecting ECU again, or a sticky vacuum membrane in the distributor (or the vacuum solenoid circuit which drives it) (if all the throttle body gubbins checks out ok, which as i've said already, requires a proper strip down to assess from the butterflies right through, and includes the spool etc as discussed before, above.)

Ah I assumed it controlled more than the CSV. Guess it won't help much then! I'd try it anyway just for kicks