Porsche Enthusiasts Club Forum

Evening all,

today my lady told me the car was a bit weak, now i admit i haven't paid much attention until today as i drive it so slowly its very hard to notice, but on motorway i noticed i no longer have that mid range pull i used too, it has a very short burst of power from standstill but then takes an age to build up speed whereas just a week ago it would pull right through it.

Whats more confusing is the cars in the best health its ever been since i bought him, and i can't see anything obviously wrong, any pointers on where to look? The only thing I can think off is my speedo cable broke during the week, and im waiting for the new one, but unless the speedo is sending messages to the ECU then i can't see how this can effect it?

Other than beaing as weak as a puppy with a cold, its running fine, where to start?

Thanks in advance guys

Spark plugs. They don't last five minutes. The cars still starts & runs but very gradually loses power. until it won't pull the skin off a rice pud. Fit a new set every 3K miles now. State of ignition components. Plug leads, coil & distributor is critical to these engines. Are the injectors clean? Do a compression test & check you don't have water in oil or oil in water! What mileage is on it & have you ever had the head over hauled? Whats the oil consumption like? When I got mine it was terrible. Got beaten up by anyone in a turbo diesel. Much dyno time has added 40hp. You can't beat putting it on the dyno then you know were you are & if your going in the right direction.

Plugs is a good start, i'll have a nose tonight, its got a new distributor and rotor, the coil is the original but i thought these either worked or didn't, or do they also become less efficient over time? Oil is religiously changed and theres no water in the oil or vice-versa, that was my first worry, exhaust fumes have no white of blue smoke either, and dosn't eat any oil. Milage is high, about 150k now, never had an overhaul, admitadly i have a new 70k engine as a spare which i would like to switch over oneday as i did have very noisy tappets, however this stoped the second i won the bid on the new engine, and has been silent since, isn't that always the way?

dyno is deffinitly a good idea, i need to find one near me

Missed something. On reading another post by Jim I noticed I forgot the fuel filter. Might explain why it goes ok until under full load.

Thanks JJ thats a good idea, i have been meaning to replace it but kept on forgetting when ordering bits, i have set asid saturday to have a look, so will pick up some bits and give it a try, i also have the new speedo cable now so will fit that too

Fixed the speedo and feels a lot better, the only thing i can think off is that the ecu uses data from the speedo in its calculations which seems unusual but its all dandy now, also changed the fuel filter which i htin kadded the the power loss as it was relaly bunged up, with the new one one it flys , thanks for advice guys