Help Please...'85 911 seems to pulse or surge...

[97*Sunshine]

I have a 1985 Targa and, when driving, the car seems to surge. I'm starting to feel like I'm in a rocking chair and hoping that it's just something simple like a relay. (and it's not my foot on the gas) It doesn't seem to happen at any given temp, rmp, or speed - but you can pretty much feel it all the time unless you're on the gas. Any advice? Also, could someone tell me if there is a valve cover torque spec, and what it might be? Thanks!!

Kim

pic attached - it's in great shape otherwise....

[Rick Lee]

Valve cover torque ain't causing this problem. Could be a fuel delivery issue, intemittent miss, DME. Need more details.

[kqw]

More specifics on surging....please:

Torque for Valve covers is 6 ft/lbs.

[97*Sunshine]

Originally posted by Richard LeSchander
Valve cover torque ain't causing this problem.

No, but I'm leaking oil around the bolts. I was wondering the torque spec so my gorilla doesn't strip them.
Perhaps I'll just buy a new gasket anyways.

[97*Sunshine]

Originally posted by kqw
More specifics on surging....please:

Partial throttle, seems to stop above 4000rpm, doesn't matter if the car is cold or hot...

[bigrubberjeep]

Don't mean to highjack the thread here, but what is the cause for intermitent back fire "pop" sounds?

[kqw]

Check the WOT switch and it's connections first. Then, cap and rotor, plugs, IC switch, hoses and lines to the throttle housing for secure fitting. This before getting into parts replacement.

How long have you had the car?

[bigrubberjeep]

Originally posted by kqw
Check the WOT switch and it's connections first. Then, cap and rotor, plugs, IC switch, hoses and lines to the throttle housing for secure fitting. This before getting into parts replacement.

How long have you had the car?

Who you talking too?

[kqw]

Sorry....referring to Kim

[97*Sunshine]

Originally posted by kqw
How long have you had the car?

Thanks for the tips.

I've had the car for one week as of today!

[kqw]

You've had the car for 1 week......

Oh Boy......

Once you get past the ribbing, get to know the folks on this board immediately......

[nostatic]

isn't dme relay a "first choice" swap for almost any problem on a 3.2?

[97*Sunshine]

Originally posted by nostatic
isn't dme relay a "first choice" swap for almost any problem on a 3.2?

DME relay??

[david914]

It's two relays in one housing that control power to the fuel pump and engine managment computer. If you look under your driver's seat, you'll see a small black rectangular box held in place by a single bolt. That's the DME relay. Over time, some of the solder joints on the circuit board inside can develop stress cracks that cause intermittent operation, and eventually a non-running condition.

[David Borden]

Our 1988 does the same thing, but it is very subtle. When accerating (using part throttle) below approx 4000 rpm's the car pulses, or hesitates. It is very subtle, but there for sure. When going to full throttle above 4K it seems to be OK. However, I dont know how hard the car should pull, the power seems fine. Is this normal?

Any input?

David

[97*Sunshine]

Ok, so the DME relay looks to be about the same size and seems to have the same function as the fuel pump relay in my VW - except for that one's only one piece and it's not under the seat. It doesn't look too hard to get at, but would probably be easier if I removed the seat. I didn't look to hard at it last night, to see the best way to get at it - any advice?

[Rick Lee]

You don't need to remove the seat. Just pull the plug and slap in a new one. If that fixes your problem, then unbolt the old one and bolt the new one down in its place. Then buy another new one and keep it in the glove box.

[126coupe]

Make sure to "true" up the Valve covers on a large (machine shop") belt sander, they tend to warp. use new gaskets ,sealing rings, and nylox......Pelican carries this stuff. Torque on those are low i believe only 9 foot pounds

[Emission]

My '86 does the same thing (a slight pulsing while driving).

I assume turbo's also have the identical DME relays as well? Are there two identical relays on each car?

[David Borden]

Could a relay cause a light surge or hesitation? I could see it causing a car to to stall or cut out, but I dont see how it would affect part throttle. I am confused on why it wouldnt affect full thottle above 4K rpms. New to the Porsche stuff, so could be missing something.

David