1969 280SEL runs erratically when hot
Hi guys. It's been awhile and I'm stuck with the same problem but I think I've narrowed things down a bit. THe car runs like a champ when cold but when it warms up it won't idle and it wants to stall and usually does. Funny thing is, it runs OK when the water temperature gets hot, let's say for twenty minutes then it starts to act up when the underhood temp gets hot. It seems to me that if it was something involving the mixture it would act up as soon as the water temp reached it's operating temperature. But it doesn't. It waits a little longer when the underhood temp goes up. Could it be that supplementary air valve? Or something else I haven't hit on just yet? Something temperature related is going on here. Otherwise the work goes well. Many thanks in advance.
1967 Jaguar E-type Series I, 2+2