starting issues after clutch replacement (engine drop)

[supercarrera82]

I have a 1982 Porsche 911, I recently pulled the motor out of it 2 to 3 months ago to change the clutch and a couple other things like spark plugs filters etc... I just put the engine back reconnected everything and put all the wires back to original setup. Now I'm going to start and the car is turning over but not firing up, it did a couple backfires but hasnt started up. Anybody have any ideas on where I should start? Any set procedures i should follow? Play with the Adjustment screw? Thanks a lot.

[blucille]

I wouldn't touch any adjustment screws....if it ran when it came out, you didn't hook something back up the way it was, maybe you knocked the distributor cap off, or didn't plug the CDI box connector all the way in, or something along those lines. Cold start to the starter motor?

[schumicat]

first thing to check is that you have some gas in tank. I would next check spark with a spark tester (even though backfire suggests it has spark it may not be strong/consistent) and fuel pressures (system and control), you need a CIS fuel pressure test kit (sold by pelican and others). google jim CIS primer for directions.

[kodioneill]

If you changed the distributor cap did you install the wires in correct order.

[supercarrera82]

there is gas :-) wires are all In the right order and the distributor cap was never touched. Right when I start it ,it starts of with a back fire immediately then turns over and doesn't start. Compression was fine when I took the motor out. Today when I started it up it backfired and broke my damn pop off valve....ne ideas when I can start? Thanks everyone

[Scott R]

Originally Posted by supercarrera82

there is gas :-) wires are all In the right order and the distributor cap was never touched. Right when I start it ,it starts of with a back fire immediately then turns over and doesn't start. Compression was fine when I took the motor out. Today when I started it up it backfired and broke my damn pop off valve....ne ideas when I can start? Thanks everyone

Ignition event is not happening. Green wire, CD box as mentioned above.

[boyt911sc]

These are the three (3) things I do before a CIS engine start-up:

1. Check the fuel pressures.
2. Check ignition spark.
3. Check for significant source of vacuum leak.

Knock on wood, I have been very successful (lucky) in all my engine start-ups and never been disappointed. Well, there was one time when the ignition timing was 180° off and corrected it.

Tony

[schumicat]

check fuel pressures, system and control. mine acted like that when return line was blocked causing pressure to be way too high.

[vince_aust]

Logical test would be to check crank reference sensors - these can easily get swapped on a engine drop. If they are connected/swapped car will not start. These are easily miss connected.

In saying this I assume the 82 is the same as the later models (84 onwards)

[Scott R]

Originally Posted by vince_aust

Logical test would be to check crank reference sensors - these can easily get swapped on a engine drop. If they are connected/swapped car will not start. These are easily miss connected.

In saying this I assume the 82 is the same as the later models (84 onwards)

Prior to 84 we didn't have reference sensors, nor did we have a DME in fact. Everything is "mechanical" The SC gets it's spark reference from the distributor.

[supercarrera82]

Thanks for all you help i will check those one by one and keep you guys posted, also i noticed a lime green wire near the fuel line, looks like it was played with because it was connected to a black line that i noticed has been cut. Anyone know what the green wire is below? Thanks

[Scott R]

That's the shielded wire for the O2 sensor. Originally there was a barrel plug on the end of the green wire, but most of them crack and get replaced by the shrink tape you see now.

[T77911S]

you have spark plug wires crossed. you are making the same mistake checking them as you did when you connected them.

i tend to get 4 and 5 mixed up. like when doing valves, i go to #5 instead of #4. dont know why, i just do it some times.

[supercarrera82]

so I changed the distributor cap and rotor and checked the wires, good news is there is no more backfire and the engine sounds a lot closer to starting. I can see the smoke coming out of the cylinders since the headers are off but its still not starting. Any ideas? Also my Bosch distributor doesn't have a mark it to show me where cylinder one is before it goes counterclockwise so I can check it when its tdc. Let me know, thanks again

[porsche0nut]

Would headers off have anything to do with it? Lack of back pressure?