missfiring

Helen · Post by **Helen** » Tue Nov 28, 2006 9:14 am

my 914 seems to have decided to missbe having only seems to be working on one side. and is backfireing.

not sure where to take it to, as Zentrum dosn't seem to know/understand this car

any suggestions?

i'm out of dosh (for cars) at the moment so car might have to go into storage...sob!

hot66 · Post by **hot66** » Tue Nov 28, 2006 9:16 am

if you can bring it north, Darren @ aircolled performance would sort it out.

Has it got wet / damp? Have you taken off the dizzy cap etc to check for moisture?

Nige · Post by **Nige** » Tue Nov 28, 2006 9:27 am

check all the usual suspects as suggested. Its a big fat carb'd motor so could've sooted the plugs up too, you could remove the plugs and inspect, clean them up and try again.

Although as you mention its on one side, the carb could be suspect for being blocked.

You could try here
http://www.peter-burgess.com/

although not a Porsche specialist he is wise in the ways of sporty carb'd motors. Set mine and Jonathans motors up (same as yours) for less £100, also included dyno setup and printout. He knew exactly what mine needed just by blipping the throttle a couple of times and listening to it, knew which choke was running weak!

Nice guy and had time to chat about cars and stuff.

impmad2000 · Post by **impmad2000** » Tue Nov 28, 2006 9:27 am

Does it need a bit of use ? or just a good Italian tune-up ?
I can take a look if you'd like.
Tim

Helen · Post by **Helen** » Tue Nov 28, 2006 9:35 am

its had a fair amount of use lately.. im a bit addicted to driving it..love the noise

its definatly not got damp (unless its condensation in the garage)

Nige · Post by **Nige** » Tue Nov 28, 2006 9:36 am

most likely, revvy and big carbs need a good thrashing daily

Helen · Post by **Helen** » Tue Nov 28, 2006 9:37 am

any advise/help most gratefully received

Nige · Post by **Nige** » Tue Nov 28, 2006 9:40 am

what's the ignition setup on that? I can't remember, is a fancy Mallory thing?

Helen · Post by **Helen** » Tue Nov 28, 2006 10:00 am

light blue touch paper and withdraw to a safe distance

roger · Post by **roger** » Tue Nov 28, 2006 7:47 pm

The distributor is a CAN SVDA with Petronix electronic ignition, but I doubt very much if that is the culprit.

If it is a complete mis-fire on one bank, check the throttle linkage is still OK. However, the most likely culprit is dirt in the carb as I suffered a similar problem last year - the 48 DRLAs do seem to be a bit susceptible to that. I didn't really get a misfire as such, it was a bit fluffy at low revs but cleared when floored. It did however pop and bang a lot.

The solution was to take the carb apart and give it a good clean - any more classic car orientated garage should be able to resolve it.

I kept meaning to put an in-line filter before the carbs but never got round to it. This would certainly be beneficial in the future.

Nige · Post by **Nige** » Tue Nov 28, 2006 8:12 pm

sounds like the problem, surpised you didn't fit an inline filter Roger

roger · Post by **roger** » Tue Nov 28, 2006 8:25 pm

Yes, I guess under normal circumstances I would have done but due to some rather unexpected events at the beginning of the year, it just got forgotten

Nige · Post by **Nige** » Tue Nov 28, 2006 8:33 pm

when is the garage getting filled Roger?

roger · Post by **roger** » Tue Nov 28, 2006 8:40 pm

Its filled now but not with cars!

Barry · Post by **Barry** » Tue Nov 28, 2006 8:57 pm

Roger: you need to change your profile: Garage filled with 'stuff', but no car

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Hope you're well

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