I think it's misfiring, can anyone help?

[CMF_Janine]

Hello and Happy New Year to all

I own a 1985 Micra DX and i seems to be misfiring occasionally, usually when driving above 60mph. A few months back we had alot of rain and my car was sitting in water for a few hours (you could just about see the tires). After this i was experiencing alot of misfire and stuttering when driving at any speed. It's only done 33500 miles and has now recently had new spark plugs, distributor cap,leads and oil change, also when i broke down on the highway the RAC replaced the points and the car has now been to an auto electrician for the timing and cambelt. This seemed to cure the problem for about a month, but now seems to be starting again. Is there something else that could be causing the problem? Oh, i also use a lead replacement for my feul, could i possibly be using too much or too little?

Any help will be much appreciated as i don't know much more than your oil change and spark plugs.

 

[CMF_frank2]

hi janine

your k10 does,nt really need a lead replacement ( its an alloy head ) but i doubt it would cause a missfire
did the water fill the car floor ?
occasional missfires can be very hard to trace, is it worse in damp weather, high revs, up a hill or light/heavy throttle ?

frank

 

[CMF_Janine]

Hello Frank

The water did fill the car floor and took about a week to dry out.

The problem is more noticable when driving up steep or long hills and yes it is a heavy throttle. I'm hoping that it has more to do with me trying to get up a hill at 60mph in 4th gear and not as my husband thinks the feul pump.

Your help is much appreciated!

 

[CMF_frank2]

janine

if it was happening going up a hill and cleared after a few seconds if you lifted a bit, i would say fuel supply ( blocked filter, lazy pump )
there should be a little electronic box under the passenger seat but that only controls the tickover when the lights are on etc and i think there are some connector blocks for the main loom under the carpets that could well corrode after being under water

frank

 

[CMF_Janine]

Hi Frank

Thanks for the advice there. I will take the car in soon and have the fuel pump looked at and ask them to see about any corrosion that may be the cause.

Janine