CarreraX

Hello all,
I just bought a 1995 993 with 79k miles yesterday. The PPI was perfect with the note that the clutch pedal is a bit low and it may need a clutch sometine soon. That isnt a problem since I plan on pitting in a LW flywheel. Anyway, Since I flew to New Jersey to pick it up and I had to drive back about 600 miles I didnt beat on the car at the test drive. I did driive it but didnt go over 5k. And it runs great. So basically, Im driving back yesterday and had to go around a semi and I had to run it up to get around him (Plus I just wanted to have a little fun) and it wouldnt pull over 5k or so. The car just felt lke bad gas or something. The car has been a garage queen for the last 3 years. Anyway, I ran the car down to 1/2 tank and filled it up and it felt like it was getting better (I mean it would rev a bit higher) but not to redline. Sometimes it would get almost to 5800 but thats it. So I ran that tank out until the light was on and filled it up again for the last 100 miles of the trip (Right at Mid Ohio actually
and it still wont go to redline. I got home at midnight and I love the car but I just need to figure this out!!! Help! PS, I did do a search. THanks!!! Mark

Guy

Just curious, What gear were you in?

CarreraX

I went down to 3rd, I stopped for gas and started out in first to second to 3rd ect. It pulls fairly strong but not like it should. ..

TroyN

Very nice-looking car! No specific ideas on a solution except to check and replace ignition components (caps, rotors, plugs, check wires, check your dual distributor drive) and call the shop that did the PPI and ask them WTF.

CarreraX

Troy, That is exactly what I was thinking. I just hate to throw money at it this soon!! I will pull the dist caps ths afternoon.

TwinDaddy

can you rev it to redline when in neutral?

Red rooster

It may be the DME has been re-chipped . If that software is not done properly the DME will back off to 6000 rev limit to save the motor .
Might be worth checking that situation out ?

Geoff
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KS400200,the oldest 964 on Rennlist,unless you know differently !

CarreraX

I just went out and it will rev to redline in neutral!

TwinDaddy

So it is not a rev limiter problem. It sounds more like the engine simply does not develop sufficient power. Wow, that could be lots of things.

Gweedo

Check the airbox and filter. Then replace the fuel filter.

Steve Weiner-Rennsport Systems

Make sure the resonance flap vacuum actuator is working,..........you may need to find a shop with the Hammer to perform the diagnostics.

95 C4 993

I had this problem with the 1st 2 chips I put in. After 9 minutes of starting, the rev. limiter would kick in about 6000rpms. Turn car off, turn back on, 9 minutes later to the second the rev limiter out kick in again. Got a Rennsport chip, no problems since.

I believe its called a check sum error?

CarreraX

THanks, but where is the resonance flap vacuume actuator? I looked through the records and cant find where the plugs or fuel filter were changed. I also took off the Dist cap (The one on the top) and it doesnt look new. I just ordered new caps, rotors, fuel filter and plugs. Hopefully one of these will do it. The car actually runs good it just missed when you get into the revs. My wife drove it and said it runs good. Is the resonance flap something that I can look at?

JasonAndreas

The engine needs to be running for at least 6-9 minutes before the artificial 6000rpm rev-limiter kicks in. You can check the ECU for fault codes using the accelerator pedal, what you're looking for is code #41.

Red rooster

Sorry , I forgot to mention the few minutes delay after start up before 6000rpm limit .
Yes it is checksum error in the DME software . It all became known in 95 !

The resonance flap will not limit the rpm , though it has an effect on measured bhp !


Geoff
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KS400200,the oldest 964 on Rennlist,unless you know differently !