Is My Cti Havin A Larf, Or What?!

[lagonda 42]

How about this for weird.

 

Months ago I was plagued with the car cutting out on left hand bends, gradually progressing to straight ahead, & even more so when raining. After checking/replacing just about everything I could think of, replacing this cable with a good second hand one cured it.

 

Well, it did for 4 months, & until we got to Italy....then it started cutting out/misfiring occasionally, but this time not direction dependent. Checked a few things out....but surprise surprise, swapping back to the original lead cured it. Another couple of months , south of France by now....misfiring again. Change lead over, & it's OK...but for how long?! Answer is presumably that these are breaking down under heat & through age....but why? Buying a new lead will hopefully sort the issue for the next 15 years or so....or is changing the lead somehow temporarily reviving something else that I should concentrate on? I know that's a stupid question....but with this car, there are never any easy/obvious fixes!

 

The weird bit? Each time I replace the cable, it misfires just as before, for the first journey. But the journey after, it runs fine & smooth. So does this car have some sort of memory, or does it just hate the idea of someone actually getting it to run OK, so tries to fool you into thinking you haven't fixed it?! How can a cable that has no breaks, high resistance, poor contacts give trouble like this? How does "resting" the cable cure it....even if only temporarily?

[MrG 3]

maybe the ingintion amp is breaking down under load and it gets a temp reprieve when you swap the lead over? Wierd.

[Anthony 1,003]

If you haven't already done so, pop a cable tie around the 3-pin yellow connector and something like a coolant pipe - that will take alot of the strain off the cable and it won't move around when cornering and going over bumps.

[lagonda 42]

Have a spare ignition amp I try each time... and coil...& it's neither of those. Will try cable tie & see if it helps.

 

Anthony.....the left hand bend issue was with the original cable, position/movement doesn't seem to be a factor when this recurs now...even when I use the original lead!

 

It's doing it again now....only this time, it's fine at start up, then misfires, but after 5-10 minutes, it seems to run fine...so could now be a temoperature related issue? Could it be the plugs? Still suspicious of the distributor lead..do these tend to break down over the years? Guess only way is to buy a new one.

 

Laurence

[lagonda 42]

Might be getting somewhere?! Have a spare but used coolant temp. sender....the blue sender above the SAD. Connecting that SEPARATELY, ie just lying it on one of the hoses, seems to improve things dramatically. This spare is the car's original, which I swapped last year in the hunt to stop misfiring then. I know these senders have a reputation for unreliability....so is my misfiring likely to be that?

 

I've tried swapping the senders & connecting, (ie screwing original into housing properly) but that makes no difference, so likely both are faulty?

 

If it helps, the car starts fine, but after a couple of minutes, it starts cutting out/jerking. Accelerating seems to clear it, & it's more prevalent when backing off. Mainly occurs between 2000/3000rpm, idle is fine.

 

Any thoughts?!

[lagonda 42]

Affected rev range more like 3000 to 4000...& it's suddenly got a lot worse...this car just hates running well for any length of time. Grrr!

[lagonda 42]

Seems to be getting worse....happy (doubtless reluctantly!) between 40 & 50 in top, otherwise it's jerk jerk jerk. GRR grrr grrr! Have noticed now that idle speed has gone up to 1200-1400 rpm....was a fairly steady 1000. I know this usually indicates an air leak...but haven't found one yet....can increased idle be indicative of any other problem?!