1989 18 gl 4 + e 156k cold start stays on constantly revving to 3k and wont shut down back to norm till temp needle is showing 3/4 to high? is there a way of disableing the coldstart unit from the carb til i can get my valver back on the road in a month or so?? any help would be great 20 = 65 miles now!!!!!
Hi davey, Sounds like a few poss. explanations 1. Electrical choke heater (or connection to) has failed. This combined with the almost inevitable restriction of coolant flow if your o-ring is original will cause the choke to stay on until everything's really hot (heat soak up from the 'zorst manifold will be the main source of this, if your coolant flow is really restricted; + manifold pre-heater if that's working, which it probably isn't). 2. A failed/failing waxstat will cause the revs to stay higher, for longer, than they should. This part can be fairly easily checked without disconnecting the water pipes. Undo the two screws holding it on and push with a Haynes-specified "30 Newtons "(imagine a 3kg weight sitting on it, with it pointing at the sky) on the pin, it should still protrude 2mm above the flange face if it's OK. 3. A cracked vacuum pipe to one of the many parts involved in the cold start system (really common). 4. Other things that I can't think of just now Not too sure how you could 'disable' the cold start stuff TBH Best of luck, Pete Edit: My No. 4 above would certainly have included Drew21's info below if I was as bright as him. Sounds like a fine explanation of the observed behaviour. I did think of the TTV, but concluded it couldn't be that as the revs were dropping to normal eventually; forgetting about the very heat soak I'd mentioned in my No.1
my best guess is the thermotime valve TTV, a black circular part towards teh back of the carb on the driver's side. Sounds like it's not getting the voltage it needs for the thermo bit of it to work (there's an electical heater inside). I predict a blown fuse or a snapped wire!!! Hence the TTV is only shutting the vac to the 3/4 point unit when it gets hot through heat soak in the engine bay. Check for 12v at the TTV plug. If this is the problem then its a quick fix for the wiring or simply block off both vac pipes that go to the TTV to disable the fast idle position delay. If this is OK then the waxstat is often guilty
I'd go with the TTV, probably a wire fallen off - used to happen to mine before I butchered it. I used to find after a long "cruise" the high revs would return as the valve had cooled down again. There has been a few posts on this recently. Oh, and a restriction of your 'o' ring is not pleasant either.....
cables to ttv was broke and some numpty had put scotch lochs on to join em back up???? got rid of them and soldered them back up and seems to work fine nowhopefully!! cheers chaps!!
