Dont worry about it , with the problem you are describing.Pull the vacuum hose of the Vacc resovoir to check you have a vacc source or get some one to watch and listen when you turn the ignition on.The flap closes and then goes open . You will hear the click.On racers you tiewrap the flap open permanently !
It makes a difference over 6000 rpm - not what you are describing!
Keep hunting and try not to get diverted by small detail stuff!What you describe is a big , fundemental fault.
All the best
Geoff

 

just came back from vertex with afuel filter, but for some reason the part number is 928 110 253 06
iam assming that 928s use the same. anyway, i found it hard to take the filter off the car since its hard to get hold of it from both sides. also, the filter in the car seems a little smaller than the new one, and biy it looks old!!!!
so, any advice on taking it off?
thanks in advance

 

Make sure you are using two wrenches to counter-hold the fittings. Put them on and then grasp both handles and squeeze together to break it apart first. (make sure you are turning the right way before honking down on them :-)).

Do the rear one first, too....

When you are done, compare part numbers of the old and new.. post the old #, and search for it on Vertex or Pelican and see what it really is... might have been the wrong one.

Mike Green
1990 911 C4 Targa

 

well i just replaced the fuel fliter, piece of cake, took me about 20 min. i tested it by blowing air in it, but it was flowing good compared to the new one. now, the old filter had only this labermahle KL 21 made in germany . the new one has 928 110 253 0 but made in italy. the new one looks a little fatter.
anyway, since i already took it out , i just went and put the new eventhough i think they flow the same, unless my method is not good.
i will take the car for a drive later cause my wife has been calling to come have lunch for the last 30 min. later

 

Have you compared your 964 to another to make sure it might just be your butt-dyno failing?

Goto the dealer and ask someone to race.

Cheers,

Mike Green
1990 911 C4 Targa

 

thats funny, as a matter if fact, i never driven another 964, and i would love to do so. i will buy lunch or dinner or drinks to any locals if they want to get together and swap cars for few minutes

 

come on up to Orlando

 

well took the car for a hard drive, and it pretty much feel the same, may a little better
can anyone post their speed at 6.5k rpm in 2nd and third gears, that will tell all.
thanks

 

Why do you want to know that? The speed at RPM wont tell you anything performance-wise...If your RPM is climbing faster than speed then speed catches up, you're clutch is probably slipping (do you have a dual mass or single flywheel?).

Cheers,

Mike Green
1990 911 C4 Targa

 

hello Mike, i think i remember reading a similar post and it was the wot switch not working. before you go spending money on wires and ect. you might want to see if your is engaging and working. i think the cam that activates this switch fell off and the car did not run right. take the car and have someone put the hammer to it . also see if you can find someone that knows what they are doing. remember its easy to speculate but no sense in throwing a bunch of parts at it as the $$$$$ can add up quick and you will still be in the same boat.

from what you said the car idles fine runs good but is missing something toward the top end. could likely be WOT switch. it is something very minor and i hope you can figure it out.

 

thanks dutchcrunch, that actually makes a lot of sense. noe, how does the wot switch look like, any pictures??

 

could be low fuel pressure. i have a bimmer that behaved the same....wouldn't pull

 

well i replaced the wires and plugs that were arcing and coil, and the car is running a whole lot better.
top end is still not strong, i noticed that my wot doesnt engage fully at full throttle, so i adjusted it from the pedal as much as possible, but still not enough. now where else can i adjust the cable??
also, in case my switch is bad, where do you buy one them??
thanks in advance

 

Wow Mike you sure are going through some bits to get the power back on, I am sorry to hear you are having this trouble. I had a similar experience with my C4, I just could not put my finger on the problem. One day I went to have my rear engine blower looked at and the mechanic offered to check fault codes. Turns out there was a dizzy hall sensor fault, the wrench talked about a new dizzy...I thanksed him and went on my way. Took the car home and removed the rubber boot that leads into the dizzy sure enough one little wire was broken. About 2.00 USD in solder, 10 mins later the car was reving like old times again. It also fixed a small hesitation when you first took the gas pedal off the ISV.

Hope it helps.