Idling Problem... Help?

Hi. I'm new on here, not big on car mechanics etc. I know the basics but not that much so please bear that in mind if you have any answers for me.

I have an 86 plate K10 which has been doing fine up til now. Recently though it's started making disturbing noises while idling and now it has started cutting out whenever the engine idles. I can start it and even drive it a bit, but it's not fun cause I have to gun the engine quite heavily all the time to stop it from cutting out.

I've got a few friends with bikes and they all told me to check the idle adjusting screw but that hasn't helped. Then I took it to a mechanic who said that everything mechanical in the engine is fine so it's probably an electrical problem. He pointed me in the direction of an auto-electric place but they'll charge me £40 just to check it over plus extra to fit any new parts. I'd rather see if I can fix it myself.

I've come up with one idea of what it could be and I'm hoping that someone here can give me an idea of whether I'm on the right track.

The idea is based on the fact that a week or two before the problem started the rear window defogger button on the dash broke. I read that there's a system in old Micras which links the defogger and the headlights to an idle speed control solenoid valve so I'm wondering whether when the button broke the switch became loose it kept turning on and off at random, even when the engine was off. If this is the case then the constant switching could have broken the solenoid as well.

I've fixed the button now but does anyone know if a blown solenoid could cause the sorts of problems I described? And if so what's the best thing to do, can I replace the part or do I need to rig it somehow so that it's not required?
 
Hi.
Unfortunately there could be a number of things causing this problem and it can be difficult to diagnose remotely.

The fast idle control your describing won't cause this. It works by detecting electrical loads which could cause the engine to slow or stall when idling, and opening a solenoid valve in the carb. to allow in more air and fuel to increase the idle speed.

So the engine will run ok if you keep your foot on the throttle. How low can you let the revs go before it dies (compared to normal idle), and does it start misfiring, spluttering as the revs drop, or just stop when you take your foot off?
 
could be a really flat battery! alternator problems... the list is endless :) gotta love the k10 though (Y) WELCOME!!
 
Your micra on an 86' C/D plate will be using the points system in the distributor instead of the electronic type used from 89' onwards. First thing you should do is take off the distributor cap, check the contacts inside it and check the rotor arm. Then pull off the rotor arm and check the condition of the points, while you're doing this you may as well clean the contacts with a little bit of fine sand paper, same with the rotor arm and cap.

Then check your sparkplugs and ESPECIALLY YOUR VACCUM LINES!!!!! They all need to be sealed and leak-free or everything will be thrown out of balance, even the timing...
I can tell you for a fact that your idle-up box will not be the problem, you can unplug this box and the car will quite happily run without it as long as you don't have everything turned on.

Check your anti-dieseling selonoid by unplugging it (Those two grey electrical plugs on both sides of the air box, one it for the auto choke, if you have one, and the other for the anti-dieseling valve), If it is working correctly then the engine should NOT RUN at all with it unplugged.
The only other suspect is the fuel filter (little white plastic thing on the passenger side of the bulkhead) they can get blocked over time if they don't get changed when they should.

Other than that just check your fuses (drivers' side footwell next to bonnet release lever) Hope this helps...
 
Back
Top