jimbeaux911

Hi, I am a new 911 owner! I bought a 84 roller, then an 82 with an engine and trans as a parts car., as it was the only way I could afford to own one of my lifelong dream cars. While I was acquiring these two to make one, I came across another one I couldnt pass up. It was stolen, so has no original VINs but has a reissued STATE ID number, so its legal to register. The car starts right up, and runs for a few seconds and then dies. I am replacing the gastank, and cleaning the injectors and lines out now, as the car most likely sat for a long time.

The fuel pump comes right on and stays running even when the engine dies, it seems to me that I read that it should not run unless the engine is running, is this true? any suggestions?

I would really appreciate any and all suggestions on how to proceed to troubleshoot the issue(s) and hopefully get to drive a 911 for the first time in my life!

Thanks in advance!
Jim

Mark Salvetti

Welcome Jim! Sounds like the start of an interesting collection.

Your 1982 should be 911SC with a 3.0 liter engine with CIS fuel injection. The 1984 would have been a Carrera with a 3.2 liter engine with electronic fuel injection.

The car that won't stay running - what year is that? It makes a difference.

The fuel pump definitely should not be running if the engine is not, at least that's true of a 911SC. It's a safety feature.

Mark

jimbeaux911

Mark,

Since it has no original VINs I am unsure of the year. The only thing I can do is investigate the engine numbers. I have not done that yet. Ill post that info as soon as I get off work today.

Thanks!

theiceman

what colour is the engine shroud ? or does it look like your 84 engine ( which is completely different from earlier models )

jimbeaux911

OK I looked up the engine numbers and the engine that starts but does not run is 1980 3.0 code 930/07. and it looks just like the engine in the 82.

so the issue is, since it starts just fine, but will not idle, what approach should I take to curing it?

Jim

Steve Weiner-Rennsport Systems

Jim,

The very first thing I would do is install the CIS Fuel Pressure gauges on it to see what your system & control pressures are. This is critical for troubleshooting CIS FI systems!

After confirming all that, I would look for a vacuum leak in the airbox.

theiceman

ok its a 3.0

if you dont have the guages Steve is mentioning there are a few obiosus things you can do while you hunt for them

if its an 80 means the fuel lines from the fd to the injectors is steel i think , thats a pain . But if im wrong and they are ny lon pop out your fuel injectors and place all 6 in containers. then take out the air filter and lift the air plate . you should hear the pump run and all 6 injectors should spry into the contaimers.

tells you if you are getting fuel. If you are not change your fuel filter , chek your pump and there is also a screen in the warm up regulator you will see if yu take the fittings off.

because it fies up im pretty sure you have spark , i think you have fuel stavation. Steves recomendations is where you want to head but i do realize those guges arent exactly lying around everywhere.

theiceman

Many people do a "mod" to keep the fuel pump running as soon as you start the ignition . Not the end of the world but as Mark says its a safety feature .

Also dont confuse the whine of the CDI with the fuel pump .

jimbeaux911

Thanks for all of the advice, I really do appreciate it! I bought a book on trouble shooting the CIS, so I will read up on the fuel pressure and guages. I am installing a new gas tank, and will try to get the pump wired correctly. I already removed the injectors, but will try to test for fuel flow as soon as the tank is in the car.

So if fuel starvation is the issue, replace the filter, and if still an issue, that would mean I will need to dismantle the fuel distribution system? is that something an old VW shadetree mechanic should tackle? or is it best left to the pros?

Vacuum leak is also a high possibility, as all of the hoses are old and dry. I will be replacing all if possible.

Thanks again!

Jim