I am still having misfire issues, and they keep appearing and disappearing. Replaced all the usual Plugs, Leads, Coils. Have checked impulses etc.

What would be the chances of the MAP sensor being faulty and sending false information and then the mixture being incorrect to cause the misfire?

oscar52 said:

I am still having misfire issues, and they keep appearing and disappearing. Replaced all the usual Plugs, Leads, Coils. Have checked impulses etc.

What would be the chances of the MAP sensor being faulty and sending false information and then the mixture being incorrect to cause the misfire?

Click to expand...

sorry..,
there are still things unanswered..,

are you 100% sure it's NOT losing coolant..??

Head Gasket is VERY likely.., unless you can confirm it's perfectly sealed

YES - you may have some electrical gremlins.. but basic mechanics are the 1st things to check..,

Charlie

99% sure on the coolant, cant be 100% sure. Water and oil both clean. - I know it can go between cylinders.

Its not overheating, its not losing power(except when misfiring obviously), although it does seem to have developed a "roar" at higher speeds which I had put down to the new set of tyres, diff tread, grip, poss rating etc. Also dependent on road surface (happened roughly same time).

This weekend I had planned to drain the coolant and refill - as its too weak concentration anyway so will know more on Monday. I wouldn't have thought HG would cause an intermittent fault though? Surely it should be evident most (if not all) of the time given my journeys are not particularly short (so engine is always hot/normal temp).

If it is HG, then its S or R sale ...... its not worth the cost IMO.

varesecrazy said:

YES - you may have some electrical gremlins.. but basic mechanics are the 1st things to check..,

Click to expand...

If it was me, I would also be putting a low current test light across the supply to the coil pack which is creating that P0352 and that would show if the problem was electrical. The light could be taped onto the dash inside the car.

Intermittent problems are otherwise next to impossible to find

judderbar said:

If it was me, I would also be putting a low current test light across the supply to the coil pack which is creating that P0352 and that would show if the problem was electrical. The light could be taped onto the dash inside the car.

Intermittent problems are otherwise next to impossible to find

Click to expand...

Not electrical minded - how would I do this??

Agree regards the issue - its becoming like a needle in a haystack.

oscar52 said:

Not electrical minded - how would I do this??

Agree regards the issue - its becoming like a needle in a haystack.

Click to expand...

I made a video

It is a bit difficult to make any recommendations because if you mess things up you could kill the ECU

My test light is a LED in series with a 4750ohm resistor. If I put the light on a 12volt source it glows just sufficiently visible for me to easily see it in indoors lighting.

The other ends of the long wires have some thin rigid wires which can be pushed into the connectors on the wire side of the connector on whatever thing I am wanting to test.

I think on your car you have two coil packs each with two wires. And you already know which one is likely to stop working when the fault occurs.

At low revs you can easily see the light blinking on and off

Good video -easy to understand.


However, pretty sure have found my issue.


Pulled it apart, to make sure the was no damp issues etc. Lead that goes to plug three, was all like white/cream dust inside. Looks like faulty lead (or possibly dodgy conection on plug and has been arcing.


Not tested it yet as replaced rocker gasket as I as at it, clean plugs etc. Havent got set of new leads so will get these in the morning.