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My car seems to be misfiring! Help

997ant

Well-known member
Joined
17 Oct 2015
Messages
176
As the title says,when pushing on through the gears in the higher rev range I think in 3rd and 4th the acceleration drops off,nothing else happens just a very noticeable drop in power no lights no noise,I change up and get boost again,but starts missing in the high revs.
Car still gets me home no clanking or loss of power under town driving.
The first thing I thought was coilpacks and or plugs? Or I hope this is all it could be....
Anyone had the same? Or can the mighty Demort advise please?
Many thanks in anticipation.
 
997ant said:
As the title says,when pushing on through the gears in the higher rev range I think in 3rd and 4th the acceleration drops off,nothing else happens just a very noticeable drop in power no lights no noise,I change up and get boost again,but starts missing in the high revs.
Car still gets me home no clanking or loss of power under town driving.
The first thing I thought was coilpacks and or plugs? Or I hope this is all it could be....
Anyone had the same? Or can the mighty Demort advise please?
Many thanks in anticipation.

Can mods move this to the 997 forum please
 
Maybe a solenoid on one of the banks but hopefully Iain will be along shortly as you say he will be best placed to give you an idea. :thumb:
 
Ant.....you're not using it enough..... :nooo: get yourself out with the boys on the next run.... :grin:
 
Lol,if I knew what I was doing from one day to the next I'd be out John.
 
Well .. hmm ..

Ok so a misfire tends to be more noticable just above idle .. a general lumpyness .

The car will monitor for a misfire .. save the planet stuff and generate a fault code and an eml pretty quickly .

Misfires are less noticable at higher rpm and you dont have an eml so im not convinced atm ..

Higher rpm so we are into turbo boost , thats a possible factor .. maf sensors again higher rpm but not max throttle could be an issue.

What would i do though .. it would have to start with a tester and any fault codes , then onto actual values with maf readings being one i would map .. misfires can be seen on a tester as can low power on any cyl so i would be checking that .

low ish fuel pressure is another .. fine on normal driveing but at high rpm you need a good fuel flow .. pumps can be a bit flakey and ive seen this on here as well as at work with low fuel delivery at high rpm.

In short im afraid there is no one thing that springs out to me as the fault .. theres a lot i would test but its a garage or a tester and check readings to find the fault i feel .
 
Thanks for the reply Demort, so not an obvious problem, I will have to get it in for an inspection when I get chance.

Would it make a more of a difference if it happened whilst in sport mode? I will take it out and try both to see if it makes any difference and post my findings.thanks again.
 

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