Really need some good advice on this one PLEASE.
2004 16v multipla with a misfire.
OK. I change the fuel pump for a new one
New map sensor
New crank sensor
New plugs
Recon throttle body
New exhaust
New lambda sensor
Still I have a bad lumpy misfire on tick over,if I rev the engine to 1400 the engine runs better but is still missing.
The coil pack was new last year.
Done a obd reading and got a new code for multiple random misfire.
Took out the plugs and they have a slight burn mark on the porcelain and it has only been running for 30 mins also the tip on the plug nearest the belts is just starting to turn a slight white.
Before I changed all this I was getting the lambda sensor code and fuel trim bank one code which have not returned.
If I start the engine I have to rev and hold for 10 secs or it stalls
Any advise would be very grateful

darkar26 said:

Really need some good advice on this one PLEASE.
2004 16v multipla with a misfire.

Done a obd reading and got a new code for multiple random misfire.
Took out the plugs and they have a slight burn mark on the porcelain and it has only been running for 30 mins also the tip on the plug nearest the belts is just starting to turn a slight white.

If I start the engine I have to rev and hold for 10 secs or it stalls
Any advise would be very grateful

Click to expand...

Sounds like it could be an intake air leak causing the engine to run lean.
Have you checked all the ductwork and connections?

Robert G8RPI.

Hi no I have not done this but will try tomorrow and post results.

OK update,cannot find any intake air leaks,but have found that the coil pack is sparking on the outer case,Started the car in the dark and noticed this.The coil pack is only a year old and obviously shouldn't be doing this.I have ordered a new pack with leads and will update my findings.

Check the coil pack, my friend replaced it on her car weeks later same problem because its new dont mean it works

Long shot : Get a garage to do a head gasket test on the coolant....Symptoms sound like a failed gasket, hope its not.

Done a compression test with 185_180_185_185 across the board so excellent there.
No problems with head gasket at all.
Will post findings when new coil pack arrives.Thank you for all your replies.

As mentioned above, could be an intake leak, this would cause lumpy idling especially, with symptoms minimised with revving.
I always used to use a "Gunsons colortune" device that fits in the spark plug hole, brilliant for seeing if the mixture is lean or rich in each cylinder, ie a lean mixture in 1 or more cylinders would make for a lumpy idle.
But not sure if your spark plug holes are accessible on the 16V.
This test can be done at night for best results, you actually see the mixture igniting through a glass window in the device!, blue mixture good, yellow is rich...light blue ...weak...

darkar26 said:

Will post findings when new coil pack arrives.Thank you for all your replies.

Click to expand...

Check the plugs and gaps before fitting the new pack, or fit new plugs that are correctly gapped. If the gap is too large or the plug is faulty the voltage can rise high enough to cause breakdown of the coil pack. Make sure the pack output insulators are clean and dry too. Don't assume new plugs are gapped correctly or a coil pack is clean. I've also had brand new, known brand, plugs that were faulty out of the packet. The root cause could still be lean running overheating the plugs.

Robert G8RPI.

OK here is my update to this bloody multipla.
It turns out that I had a leaking intake manifold gasket and exhaust manifold gasket which was giving me the irratic tick over and misfire.
He wgaskets fitted and everything is spot on.Thanks for the replies.

MultiplaAbarth said:

I always used to use a "Gunsons colortune".

Click to expand...

a really good bit of kit i use them to set my bikes up along with vaccuum gauges , you can pick them up for about 15squid , the colour of a plug can tell you alot of things if you know how to read them properly

Totally agree.