Strange Engine Performance!

[Vincent Hill]

I do not even know how to Search for this?

I just finished installing a new Air Box and new Rubber Boots between the box & Runners. It took a while to find out how to set the A/F Screw.

Now the adjustments have been made and the engine starts on the second try and is a little Cold Blooded (Takes about 2 or 3 minutes before you can leave the Curb.

Now to the problem, when I step on the gas Pedal the car accelerates smoothly. The "Problem" is sometimes it is making "SERIOUS" Power where I almost cannot control it and MOST of the time it just revs up with a moderate amount of Power?

It "Sounds" like a 4 Barrel Carb with the Rear 2 Barrels kicking in vs a 2 Barrel Carb!

It is very hard to duplicate this. I am looking at the Micro Switch and have bent the arm down to keep it active longer and I have tried to check the frequency valve but could not feel it pulsing.

All I know is I WANT the Performance of this "Sometime" running engine. I did not know it could run this hard!

(I have re-gaped the plugs from 0.050 down to 0.035) Have the Permatune adjustable Ignition box and have relocated the coil. I also just re-set the timing. I also took a 10 MM wrench and 1 at a time I loosen and tightened the Lines on the Fuel Distributor to see if anything was not running. As soon as I cracked the lines the engine dropped RPMS so I know all cylinders are running.

I seem to be able to make this happen only when I carefully give it the gas from a dead stop, it may happen. When I mash the Pedal to the floor, it does not usually happen? I have never played with the Dip Switches on the Ignition Module. I feel it is more of a fuel issue than Ignition but who knows?

[Vincent Hill]

Fixed! Thanks to a person that never posted on this thread "John Walker"!

I started reading a lot of threads that were having all kind of problems that were like mine and saw where he stated that if the O2 Relay was bad, these kind of things would happen.

I just came back from seeing my friend at the Porsche Dealer where he sold me a Relay for $6.77 and the car is Flying!

All I need to do now is a little more adjusting to the Idle screw and the A/F screw to make to get the best compromise between starting perfectly and a smooth Idle.

[Bob Kontak]

One step at a time. Focus your search on CIS throttle response / CIS problems.

Not clear if you don't know how to search or just can't figure out a search term. Use the advanced search option.

Try to describe the problem a little better. When you mash the pedal does the car rev smoothly but in a "whimpy" fashion? Is there a hesitation like the engine is trying to catch up with itself?

Did you use a dwell meter to adjust the a/f mixture?

There are several things you need to labor on to nail down the issue(s) and the searches will get you started.

[Bob Kontak]

Sweet!

[Vincent Hill]

Bob, I "Still" have my old analog Dewll / Volt meter. I may need to put a new battery in it I plan to look this weekend and see what it is reading.

Thanks!

[Vincent Hill]

Latest Update. I went to hook up my Fuel Pressure Guage only to find that nothing Fit! I had everything set for the 1976 911s that used Plastic lines and Banjo Fittings. So now I need to set everything up for the metal lines.

Thinking about the Warm up problem, I took the 16 MM Bolt out and measured the Shims on the Spring that controls the Fuel Distributor pressure. There were 2 shims that were about 0.018 thick. SO I removed one and started the engine. It started a LOT easier and warmed up fast compared to what was going on previously. So now when I can read control pressure, I will then know if I need to remove another Shim!

Thanks everyone!