Balazs 911

Hi there.

I have now spent the last 5 hours searching and reading of problems with high mileage 993s. I am a complete tool when it comes to technical questions and my abilities doesnt go much further then changing battery.....

So my problem is this: Car is not fast enough. It does 0-60 in just under 7 seconds. I had a few Porsches and the last one I had (964) was considerably faster in acceleration. Today I drove a friends 993 and it is like night and day. My car is simply missing the "kick". Well up in speed it does 170mph without problems but as I said, it has very bad acceleration and its not very responsive at all.

This far from what I have gained from my search it can be the varioram system that doesnt work properly or the dual distributor belt (these 2 seems to be affordable to fix but I might be wrong) . I checked in the engine and saw some sparks in one of the distributors (cant be right I guess).

Have anyone here had similar problems or do you have any ideas what else the problem could be? If you post old threads that can be useful I appreciate that to.

Best regards,

Balazs

PS The car is a 993 C2 from 1996 with 104K miles.

FisterD

Distributors sparking is not good.
Maybe this will help pcarworkshop distributor

Steve Weiner-Rennsport Systems

Hi,

There are several things that can affect power output and these should all be thoroughly checked out. The VERY first thing to do is a leakdown to ensure that the engine is healthy.

After that, I would:

1) Make sure the resonance flap is working

2) Make sure the Varioram stacks are functioning

3) Make sure the distributor drive belt has not slipped or is broken

4) Check cam timing since Porsche didn't always do a precise job at the factory and the chains do stretch over time.

Marlon

High milage - could also be a bad cat and/or dirty valves and intake system. Either one side or both sides of the cat could be partially clogged. A good mechanic with an IR handheld thermometer should be able to help. Also a good engine top end flush with SeaFoam thru the vacum system will help too. I had a similar problem that a replacement cat and SeaFoam fixed totally.

Balazs 911

Hi again,

I changed the distrbutors, the belt (was broken) and the airfilter (was complitly blocked) but still I dont have the power.... Also the varioram was tested for vakum leaks but everything is at it should be....Will go and dyno the car its no way I have the full 286hp. I am also thinking to replace the cats with bypass pipes but not sure if it is worth it. Regarding the valves and the intake system I guess the engine has to come out, sounds like a big project but if I dont find the problem I will have it done. Any further input or ideas are very welcome.

All the best,

Balazs

Steve Weiner-Rennsport Systems

Is the resonance flap working properly?

Did you have a shop actuate everything with the PST-2 to make certain its all working correctly?????

NP993

This sounds like a HORRIBLY maintained 993. I suggest, as Steve does above, that you get the codes checked; and then, do full maintenance on the car -- especially the plugs, wires, caps, rotors, etc.

But before that, I'd verify the health of the engine. Depending on how long you drove the car with a broken distributor belt (and where the distributor rotor came to rest) you could have seriously damaged your engine. Twin-plug motors don't like running in single plug mode for long.

Balazs 911

I will take the car to the local Porsche dealer but I am worried its going to be very expensive (they charge over 4000 usd just to change a clutch....) Updates will follow....

Balazs 911

I am changing all the ignition cables, rotors and plugs this weekend. Have not had time to drive or fix it but I went to a local Porsche center and I have very bad ignition on cylinder 4 5 and 6. I had the car HP measured today and it was worse then I thought.... I have 204 hp instead of 280plus... The torque wasnt impressive either 265nm..... So much for route 66 motors.... :-(

Terry Adams

Tell us where you are and I am sure someone will chime in with local independent mechanic recommendations. Dealers are more focused on newer models. And expensive.

Balazs 911

Hi how can I insert a picture without an URL adress? I have a graph saved under my pics but I do not have an adress to link from.

Thanks in advance,

Balazs

Howdy993

A membership could be the best money you spend this year. Users may not be allowed to post photos.

Best of luck with the car.

sleddog

When you take it in, have a leak down test performed. The results could give you some insight into your power loss.

Balazs 911

Thanks for the answers, I am now changing cats, lamdas and cleaning the injectors.... After the change of all cables, sparkplugs, distributors my hp went to 247 hp and the torque also went up. I though it would have been a good idea to post the graph from the latest "testrun".

Have a nice day all,

/B

TMc993

247 HP at the wheels...Wouldn't that be about right for 285 at the flywheel (14-15% loss)?