First mechanical(?) problem in 17 years.......

[megsy]

Hi Guys,
I've owned my GQ Y60 manual 4.2 EFI Petrol (203,000km) from new and for the first time, I have a problem.
It has been misfiring (idling rough) and was advised by the mechanic to run it on premium with Nulon injector cleaner which I did on a trip I have just completed (2,000km).......no change.
I was then advised to have the tappets adjusted which I had done today.....it's now idling worse than before!
I am going to have a compression test done next (subject to the feedback I get from here on the forum).
I recently had a new dist. cap, rotor,leads and plugs fitted.......it was running fine before this ( could it be a faulty plug ?)........I'm a bit doubtful about the latter because it would idle normally and then the next time I started it up it was rough and so on.
I had a major service done at 200,000.......when the trouble seemed to start.
HELP AND / OR ADVICE TRULY APPRECIATED.

[boots]

leads and plugs , thats what I would be checking . Are they a reputible brand these parts ?

[TimE]

leads and plugs , thats what I would be checking . Are they a reputible brand these parts ?

.......yeah, the simple things first, also check the fuel and air filters

[MudRunnerTD]

Take it back to who did the work and ask them for an explanation. Their parts have caused a problem with your car

[Parksy]

I basically changed everything on my 4.2 efi, even got new injectors, but still had running issues. New fuel pump helped alot, but wasn't the cause. Turned out it was the inlet to head gasket. Just dried up and leaked like a sieve. Replaced it(despite being an awful job) and the difference was night and day.

[pearcey]

Get the compression check done and if possible have the ignition system checked on an oscilloscope this will find most electrical faults with out guessing or changing parts unnecessarily

[macca]

Can you still do it the old way?
Disconnect a plug lead one at a time. If one makes no difference its the one giving trouble.
Run the engine at night with no lighting around to see if any leads are showing sparks where they are tracking to the metal parts of the engine.

[megsy]

A couple of things..........1).two mechanics suggested I just drive it as it is !!!!!!!!!!!!!!!!!!!!!! I was "gobsmacked" to hear such inane comments.
2). On my 2000km trip I was towing my 5 metre caravan(1.2 tonnes) and the fuel consumption was the same as it's always been, (4.3km/litre).

[Bloodyaussie]

I basically changed everything on my 4.2 efi, even got new injectors, but still had running issues. New fuel pump helped alot, but wasn't the cause. Turned out it was the inlet to head gasket. Just dried up and leaked like a sieve. Replaced it(despite being an awful job) and the difference was night and day.

I find that interesting as I have been having trouble for a little while now and it might be worth looking into??

[93patrol]

Yeah but BA you drowned yours in mud that why its running rough.

I would say leads and spark plug would be your issue IMO


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