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ello all

Car has had an idling/misfire issue, kept on cuttin out and misfiring. Replaced the spark plug leads and thats improved on the general running. However it does still cut out (only when engine is idling or approaching junctions/lights) occasionally, but what i find most worrying is the fact that if i've got the engine running at an idle and i switch on any other electrical accessory in the car (rear heated windscreen, fan blower etc..) that will kill the engine instantly. My thought is the alternator/voltage regulator might be stuffed, i need to check the output voltage but i'm pretty sure thats the issue. Any suggestions as to what might be up with it?

Cheers

Paul

start the car and then test the voltage at the battery poloes which should be arround 14v regardless of engine speed or load
if its low all the time check alternator wireing and maybe the alternator if it raises like mad with revs then its the regulator
other than thet get the battery checked and possibly check the ign switch is making good contact

Thanks for that.
Voltage was 14V and stays constant throughout engine speed. Will get and have a look at the ign. switch and battery, unless anyone else has any suggestions.....

Cheers

Paul

idle control valve? would this be affected by electric current?

If the alternator is charging, it sounds more like an ignition problem.

Have you checked the dizzy cap and rotor arm ? The blue temp sensor can cause similar symtoms to yours, if it's faulty.

hardhitter wrote:If the alternator is charging, it sounds more like an ignition problem.

Have you checked the dizzy cap and rotor arm ? The blue temp sensor can cause similar symtoms to yours, if it's faulty.

yeah these have been replaced. Will check temp sensor as i've noticed that the temp on the dash hardly ever gets above 70 degrees unless the ambient temp is warm then it will head up to 90 or so. Had initially thought thermostat was knackered but will instead investigate the temp sensors...

cheers

Paul

That might just because you're running a 1-litre mate, they simply dont get warm... You might get the fan come on once or twice in summer in a traffic jam, but in winter there'll be days when the needle just doesnt move (and it becomes a bugger to restart). Dizzy cap, rotor, sparks all sound like good ideas... did you change =all= the spark plug wires for decent types (inc from coil to distro)?? Made one hell of a difference to my engine personally..
Or maybe somethings shorting out somewhere..

Ah well still no further forward
Have so far replaced plug leads, dizzy cap, rotor arm and blue temp sensor. Have used way too much carb cleaner i reckon! and given it all a good cleaning. The engine still doesn't seem to want to consistently rev at idle. Sometimes it dips low (500rpm) and cuts and sometime it will recover from this and stay idling (albeit a bit rough). Strangely enough it works fine for 40 miles or so if i disconnect the battery and then reconnect it. Only things left to try are taking off the idle control switch and stripping it down to see if the contacts are stuffed (thats presuming it has contacts!), looks like i'll need to remove the carb to get to the mounting bolts for that though. Failing that i was going to adjust the throttle limits to stop the switch from being actuated (reckon this is a bit risky as i'm not entirely sure what effect it could have, so its pretty much a last ditch effort). Any more thoughts (apart from get rid of the car )

Paul

engine to chassis earth