getting my engine started after a rebuild

[osidak]

I finally got my starter issues worked out and now the engine turns over just fine. A little forword though. The engine rebuild took me a bit longer than I liked so it sat for for some time. With that in mind and a nearly empty tank I dumped 3 bottles of techron and 4.5 gallons of gas into the tank.

When I try to start the car it will run for 2 seconds or so. I believe all cylinders fire at least once maybe twice then the car dies. I have tried bleeding the system by turning the ignition on and lifting the air flow sensor plate. Should I hear the fuel pump running? Should I hear the injectors doing their thing? I haven't disconnected the fuel lines from the injectors yet should I?

What steps should I take next? The Car is a 78 911sc.

Thanks

osidak

[zuffenhausen]

Unfortunately, I don't have your magic answer, but a couple of things to consider:

The ratio of Techron to gasoline seems a bit high, but I guess that stuff burns about as well as gasoline. You might want to try diluting your fuel down with a few more gallons of gasoline.

As for the CIS, try pulling one of the lines off an injector and then holding up the throttle plate while you turn the engine over. You should see significant fuel coming from the line.

Most fuel pumps do make some noise, so generally, yes, you should hear the fuel pump running. I don't think you'll hear anything from CIS injectors like you do from pulsed injectors.

Hope that helps. Best of luck. If you're ever heading to Raleigh, drop me a line and stop by.

-zuff

[Doug Zielke]

Omar,
I remember Leland mentioning his freshly rebuilt motor was very hard to start for the first time. He reckoned it needed a lot of cranking to bleed out the air from all the plumbing. When it finally started, all was well.

[Superman]

My procedure: first run the fuel pump for a half-minute or so to get the air out of the system, or most of it. The gasoline cycles through the system, so you will hear the air being discharged into the fuel tank. I jump the fuel pump to do this. Next, put the fuel pump back in and turn on the key. Go back to the engine and lift the air flow sensor plate. This should make the fuel pump come on and it should also make the injectors spray. Yes, you can definitely hear them. They sing, kind of. Perhaps you should remove one for visual verification they are spraying.

If you car starts and runs very briefly like you say, then most likely the cold start valve is working but the injectors are not. This is too low fuel pressure (fixed by running the fuel pump for a bit) or perhaps something like a bad switch at the sensor plate (if lifting the sensor plate with the key on does not make injectors spray).

[Early_S_Man]

osidak,

What Super is talking about ... reading between the lines, is pulling the red fuel pump relay and putting a jumper from terminal 30 to 87a. The relay terminals are labeled next to the pins on the underside. Jumpering those terminals turns the fuel pump on as long as the ignition switch is on.

[Wayne 962]

Yes, try 'meowing' the injectors, as I like to call it.



Also check to make sure that your plug wires are hooked up properly. I have been known to make this easy mistake at least once in my life in a very similar situation.

I also like to pull the harness on the CD box and crank the motor for at least a minute or so to build up oil pressure, and make sure that nothing is about to go wrong...

I'm not sure if the SC pump runs when the key is on, or only when it's cranking. I think it's on all the time. The fuel runs in a circle - to the pump, to the injectors, and then back to the tank.

Fill up the rest of your tank, and then let the fuel pump run for about an hour to mix your fuel. I think it's one bottle Techron per tank, right?!?

-Wayne

[osidak]

The heavy dose of techron was to get rid of any fuel varnish that may have formed while the car sat (It sat for a long time).

I do not hear the fuel pump running (I don't remember if I ever heard mine like I have heard others) I will try jumping the fuel pump as Superman said (thanks for the clarification Warren) and I will also pull an injector line.

I am pretty sure I have all the plug wires hooked up right but I could be wrong. Before attempting ignition I pulled the fuel pump relay and coil wire and turned it over to build oil pressure. I then found an oil leak (loose chain tensioner fitting) and then I found a fuel leak when I put the fuel pump relay back in (cold start injector)

Are there any electrical connections to the fuel distrubutor or injectors? Is it possible to have gotten something like that hooked up wrong?

Again Thanks for the help

[osidak]

SHE LIVES Happy Happy Joy Joy

Ok I am happy please excuse me.

I pulled the number 4 injector line and switched on the ignition and lifted the air flow sensor plate...... A little squirt of fuel then nothing. Refering back to the Superman/Warren advise to jump the relay I tried again and this time I saw a wonderful flow of fuel. I hooked every thing back up and bled the system by lifting the sensor plate and she fired right up. She didn't like me giving it any throttle for a moment or so and the intial idle was hunting but then she smoothed out.

I don't have the muffler on it (but I do have the heat exchangers and crossover pipe). For those who have wondered she is lound and sounds like a really pissed off VW on steroids Tomorrow I will get the gear linkage sorted out and get the muffler on and back it out of the garage and let her run a bit. Must have po'ed the neighbors though cause it is 9:30 pm as I type this

Thanks for all the help guys.