[flatsixcrazy]

Hi all,
I have finally gotten the "project" up and coming alive two weeks ago. New plugs, cap, and rotor, belt, air filter, valve adjusted and new used HEs. The 78SC cold starts and idles great, but quickly dies when I press on the accelerator pedal. Actually, this is how it happens everytime. It idles and I press on the gas pedal, it would initially hesitate when I put my foot on the pedal to give it some gas, it would gives me a couples of pops in the air box, revs up to 4-5 Krpm, and dies when it came back down to idling rpm when I take my foot off. After that, it would not restart until a few hours later and I smell a lot of gas. I have check the sparks at the plugs when it would not restart and the sparks looks fine. Has anyone have this problem before and can you help. Thanks in advance. Andy

[matt de maria]

I would check the fuel pressures especially the warmup regulator pressure circuit. It sounds as if the cold start valve is working ok (starts normally) ; but that the mixture gets too lean off idle (maybe warmup regulator clogged or sticking -common if the car has been sitting for a long period of time). At this anbient temperature I would expect the warmup regulator to have a value of about 2 bar (check specs) and to increase to about 3.5 bar (again check specs) when engine is warm. This is assuming that everything else looks "normal".

[OldTee]

Mat gives good advice. I had the same problem. The car sat for 3 years. I found the accumulator diaphram was rotted. I also replaced the fuel filter because of the sitting. The presssure test will tell you if the accumulator is a possible trouble spot. Hope this is not your daily driver, at least not yet!

[flatsixcrazy]

Matt and Oldtee,
Thanks for the tip. I will check the WUR pressures. I have sometimes before I need to finish this project. I'll head down to sears to pick up the pressure gauge tonight. Thanks again. Andy

[flatsixcrazy]

Hey guys,
I stopped by Sears to pick up a feul pressure testing gauge but what they have is not the same as the one showing in the bentley manual. Does anyone know of a place they sell a feul system pressure testing gauge for 911s?. Also, I tested the feul pump on my 78SC lastnight and here is what I found. With the original relay, I got no feul pump when the ignition is on, but cranks and starts anyway. I swap the red relay with the black relay in the trunk and the same thing goes. I then jumped the 30 and 87a terminals of the socket and the feul pumps kicks in with ignition on. Does this mean that my relay is bad or is it something that supposed to be?. Andy

[matt de maria]

I bought mine from Snap-on 20-25 years ago. They possibly might still carry them. Mack or Matco also carries them now. I think KD still makes them.
1976 and later cars-the fuel pump is triggered (through relay) by the sensor plate microswitch behind sensor plate air horn. When you crank, sensor plate lifts up, switch turns on energizing relay.
Black and red relays are basically the same. Red relays are dioded and internally fuzed at 30 amps. (Diodes are used to suppress voltage spikes from inductive loads like motors) Black relays have no diodes and (I believe) are internally fuzed at 25 amps. For testing purposes they are interchangeable.

[Jase007]

Andy:

I picked my FP tester kit up from Pelican or Performance Products several years ago. I had to contac the MFG b/c I needed (or it wasn't included) an extra adapter to connect to the fuel system on my '76.

Jase

[CrewChief]

For us home guys try BMP (specialize in BMW stuff). They have a couple different fuel pressure testers with appropriate adapters for CIS. About $50.

Otherwise for CIS you will, as Matt says, need to go to SnapOn, Mac, or MATCO. Good stuff, and lord knows the SnapOn kit has EVERY adapter in the known universe. But, the cheap kit is $175.

Found it:

http://www.bmpd.com/index.shtml

[Jase007]

John:

My mistake ... that is where I got my CIS kit as well. It is also where I drop more $ on my other german car

Jase