Lack of power when pressing gas pedal

[htbetz]

My 2.7 911 has suddenly lost all it's pep. When pressing the gas pedal the car accelerates like a Pinto. I changed the fuel filter that was a bit clogged, that helped a little. The weather has been super damp here in the northeast, my garage is like a rain forest. I cleaned the distributer as well as all plugs with no luck.
What else can I do?
Thanks
Harry

[stormmaster]

have you tried it without the air filter?.....maybe its clogged.

[Grady Clay]

Harry,

Stop driving until you confirm both cams are in time. One cam out of time or stopped can make the engine feel even less than a 4-cylinder Pinto - in fact it is running on three cylinders. There can be many other less complicated reasons for the lack of power but driving a 911 with a cam out of time can lead to a destroyed engine.

The easy test is to measure the cranking compression. This test is worthwhile in its own right to establish proper engine condition.

Other simple reasons can be ignition out of time or points closing up. Is the tach operating normally?

Have you measured the fuel pressure while driving?

Did the throttle cushion brake? It is a little, round device above the transmission mount. Check for full throttle.

EDIT:
Take a hair dryer to the cap and ignition wires. (Do not do this if ANY fuel vapors are present.) The moisture may be the culprit. If in doubt, replace the cap, wires and plug connectors - good annual service in any case.

Are you sure that the performance changed when you changed the filter? I'll again want to know the fuel pressure while driving. Measure the fuel flow, open circuit with a hose back to the fuel gas cap.

Best,
Grady

[ChkbookMechanic]

Another item I'd check would be the throttle linkages and cable since they should be easy to check. When I bought my 911 these were out-of-wack and the car had no acceleration and was very lethargic.

[dshepp806]

Good points Grady (we are fortunate to have a real P-wrench chiming [and I didn't get an "information" invoice],...all of us are grateful for your time here....)

Aside,..

I'd make sure ALL is dry FIRST...replace as you feel necc......how old are the dist, wires, etc.,?

Air Filter good (Stormmaster's recco...)?

Best,

Doyle

[T77911S]

does the car idle fine ? how is it at steady speeds? does it run rough? is it better cold or hot?

i would look for the easy stuff first.
check for air leaks. do you have a pop off valve? is it closed properly? check timing, make sure you are getting full advance. check the vacuum line to the warm up regulator (WUR). pull the vacuum line off, you should feel vac on the line and the engine should change. pull the vac off the dizzy, RPM's should go up. is the fuel pump providing enough fuel. any chance you got some bad gas? not from eating beans either.

[Christien]

Originally Posted by ChkbookMechanic

Another item I'd check would be the throttle linkages and cable since they should be easy to check. When I bought my 911 these were out-of-wack and the car had no acceleration and was very lethargic.

I agree. A couple years ago I was doing some minor work at the track and suddenly was way down on power. Went for a quick test drive outside the compound to see if I could figure out what was wrong. One of those "d'oh" moments...I had forgotten to reconnect the linkage on the bottom of the gas pedal when I removed the floor mat, so I was just mashing down on the loose rod, probably only getting 1/2 WOT....

Always check the easy stuff first

[tobluforu]

Give it more cow bell.

[htbetz]

I have checked everything that you kind folks have suggested with no luck.
I did discover a fairly loud valve tapping noise so that's gonna be my next project this weekend.
Can mis-adjusted valves cause this lack of power?

Thanks
Harry