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Engine misfire at 5000rpm

PanozGTR

Well-known member
Joined
5 Jul 2017
Messages
126
Out enjoying the C2s on Saturday, just stretching it's legs a little at about 5000rpm when the engine started to misfire and the engine management light started to flash. Luckily l was close by to Parr Motorsport so dropped in to see if they could help. After checking the fault codes they found the misfire on cylinder 4. So l assume that it's probably a spark plug or coil pack. I limped back home and just had time to book the car in to Precision Porsche before they closed on Saturday afternoon. Fingers crossed it's that simple.
 
Coil packs are a pretty common consumable on these. I had low speed misfire and could hear it at tick over.
 
I expect it's just a coil .. i'll probably get the job so you will know soon enough :)

High rpm and its normally a spark related issue .

I do know we are pretty busy on Monday though .. 10 jobs were listed when i left on friday .
 
Hi Ian. I luckily managed to get booked in for 2pm. We spoke at the cars and coffee a few weeks ago, l have the Macadamia C2s you may remember. Look forward to seeing you tomorrow.
Cheers Denis
 
Denis i remember you well :)

your wife is as passionate about these cars as you are :thumb:

I tend to get the jobs like this .. no guarantee but i expect i will and it sounds like a simple coil or plug fault .. i'll know more when i look at it though .
 
Dropped the car off at Precision Porsche today to check out the reason for the misfire. Very pleased to say that Ian (deMort) is sorting things out for me. He walked me through the job at hand which was great. Bloody hell there's a lot of stuff to remove to gain access to the spark plugs and coils, rather him than me. So hopefully will pick the car up tomorrow. I'm expecting at least another 200bhp at the wheels when Ian has finished with it. That just leaves the painful bit. Now where did l put my wallet :dont know:
 
Duplicate
 
Hopefully you don't have a problem with me sharing here what i found and did .. if you do then please pm me and i'll delete it ..

Non present fault code for a misfire on Cyl . 4

Values of sensors found to all be in spec .. some adaptations to the fueling which is pretty normal and nothing that stood out as a problem .

Fault code cleared and adaptations reset .. it will take a while for the car to re adapt and settle down .. again normal .

The fault is a high rpm fault only so non present at time of checking , this is consistent with a weak spark , it could be other items but with something that's not at fault at time of test then we have to go for the obvious faults .

Ive replaced the coil and spark plug on that cyl but due to the work involved i felt it best to change all the plugs whilst i had the car apart which we spoke about .

i would suggest we put a tick in your service book on the minor service to say plugs changed .. you will now have the plugs done on a minor service and not the major service going forwards .

In other words your next service will be cheaper .

I road tested the car at 5k rpm in 1 , 2 and 3 gears and had no further fault codes or misfires .

I'm not comfortable trying the same in any higher gear but i did the above several times and had no recurrence of the fault.

On the VDC there were a few fault codes but all other than one were what i would call battery related .. not a flat battery as such but a low charge one which often happens on a startup so of no concern .

The active code seems to refer to the side lights .. the headlight switch does not illuminate when the side lights are turned on but does when dip beam is on .. it would need investigating but i suspect a headlight switch would be needed and its really of no concern i feel so not worth the cost .

i'm afraid as i often say .. i have no control over pricing at my garage , but it's not a lot more than a plug change imho.

Car needs to be cleaned which will be done tomorrow morning as i didn't finish the car till 5pm .

EDIT ..

I'm afraid i didn't quite get 200 bhp :)
 
Car now sorted thanks to lan at Precision Porsche. Just can't recommend them enough. They fitted me in quickly even though they are obviously very busy. Great work by lan who completed the work in super quick time considering the strip down required. Spot on with the diagnosis and all buttoned up in no time. Excellent service, money well spent.
:thumb:
It's quite surprising how sharp the throttle response feels with a new set of plug's.
The car was also washed and polished to perfection. Happy day's
 
Please make a note in your service book that the plugs have been changed so that they are not done on the next service in 2 years .

i've since confirmed by looking at another car that the light fault code is indeed the headlight switch should illuminate with side lights on .. yours only comes on with dip beam selected .. hence the fault code .

Not really an issue i feel :)
 
Your fella has already logged it in the service book. As for the lights, as long as they work it is not a problem to me. Thanks anyway.
 

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