johnkmcguire97

I picked up '79 to restore, but cannot get it to start. When I bought it, the previous owner told me it would need a new external fuel pump. The old pump worked but it appeared to leak. It would turn over, fire up for a second then die. He told me it was because there was not enough fuel pressure to keep it running.

I replaced the external pump with a new one. Put in a few gallons of gas and tried to start it up. Same result. Seemed to run for a split second longer although that could just be my optimism getting the best of me.

I pulled the internal pump, hardwired it to a battery and realized it was dead. After some searching on the forum it seemed like I could replace the internal pump with a fuel screen and run it just on the external pump. So I installed the fuel screen, poured in 2 gallons of gas and tried to start it. Same result. It will run for a second then die.

What is next to check. Please help.

danglerb

When a CI$ injection system sits for a long time, plan on replacing the fuel distributor and WUR or rebuilding both, as well any other parts like dampers or regulators, maybe injectors. The way to test it is with a CI$ injection pressure set of test gauges.

GlenL

OK. That's horrible advice.

My CIS car had sat for a couple of years. Took some time before it cleared out and run well. Took some time but didn't require any expensive parts.

If you replaced the pump did you replace the fuel filter? Can't hurt.

You need to work through the system. Use a timing light to establish that it's sparking consistently. Check that the air door moves smoothly. That's where the air box attaches to the lower plenum.

If sparking, then use some starter fluid to help it along. Certainly needs some fuel to flow to remove gunk. Line up some SeaFoam or Techron to use once it starts running. Use that at full to 2x strength for a half tank of driving.

Check the vacuum hoses for any that are disconnected or really cracked.

My guess it that the injectors have dried fuel varnish in them. Once it starts running and you drive it that will clear out.

johnkmcguire97

I have not replaced the fuel filter yet. That is next on my to-do list. It is definitely getting spark. It fires right up, sounds like it fires all cylinders but dies immediately.

I will check air door, vacuum hoses and get some starter fluid.

I will rebuild things if necessary.

Please keep the advice coming.

tailpipe

check and make sure there isn't another fuel pump beside the pass rear wheel it will be on the same side but opposite to the fuel filter you should change the filter regardless you might have to check and make sure the plunger in the fuel distributor isn't siezed if you have fuel coming out of the carbon canaster at the front right of the car then the fuel accumulator has ruptured inside also make sure the timing belt hasn't jumped a few teeth if you need more help pm me and i can give you my phone number i will be close to dearborn MI sunday night if your close


paul

V-Fib

Not a good idea, IMHO.

Not trying to be an ***, but do some home work and do searches on:

1. CIS
2. Bridging the fuel pump.
3. OB won't start (run)
4. Workshop Manuals
5. Take Paul up on his offer if you can

Most of the information you are seeking has been regurgitated many times. All here will help, but there is a lot you can do on your own with a little initiative.

You really will need to learn more about the CIS system to trouble shoot it correctly.

Once you've become familiar with the system, it is not that complicated.

Welcome to the Asylum......

James Bailey

Never ever believe what the prior owner tells you.....odds are they have no clue. If they did THEY would have had it running and sold it for a LOT more money. They car is starting on the cold start injector the electric one on the front of the intake. The CIS SYSTEM is not passing any fuel. The fuel filter is just fine and would NOT keep it from running except possibly at high load high rpm. You either learn a great deal about how a CIS system works and get a couple pressure gauges or you can throw parts at it trying to get lucky. As mentioned some of those parts are expensive.

Sailmed

+928
The CIS fuel system is one of the easiest systems out there - and almost bullet proof! Find a bosch CIS system book and go through it from one end to the other.
Take Paul up on his offer! That is one of the most wonderful parts to this forum!
Before you get the car running - I highly suggest 10 ft of 5/16 EFI fuel hose and rolled edge clamps. Do your car a favor and replace all of your old soft fuel lines ahead of time! It does no good to get her started only to "fire it up".

johnkmcguire97

I found the guides on rebuilding the WUR and CIS fuel distributor. Any advice on which one to rebuld first.

James Bailey

Rebuild neither one first.....get some pressure gauges and TEST ! But more often than not it will be an issue with the warm/up /control pressure regulator since that is the "brains" of a brainless system.

Lizard928

Do not disassemble the fuel distributor, many people have trouble getting it to seal.

Sailmed

A systematic approach does not involve rebuilding things that have no need for rebuilding - It takes only moments to trouble shoot and fix, while it involves the same application of knowledge and the proper tools.
Not to be harsh - But isn't tearing something apart before you can even understand how it works like throwing the cart before the horse.
um... then again - please disregard that remark if you still drive a 911.

johnkmcguire97

OK, I will get a pressure guage set and go through the system. I have no problem troubleshooting the system correctly. If anyone in Vegas wants to lend a hand I would appreciate it.

danglerb

OTC master fuel injection test set, used since I am cheap, is my first preference. Others have been happy with the JC Whitney and Harbor Freight CI$ sets, but make sure it includes Bosch CI$ test fittings.

Some of the Pelican guys have CI$ cars and gauges, pretty sure a couple are at least part time in LV. and might be willing to bring their stuff by to give you a hand. http://forums.pelicanparts.com/porsc...chnical-forum/

johnkmcguire97

I got it started, but it dies if I let the rpm drop below 2000. Its progress at least.