Tinker951

Ok, had to tow a '87 951 to my mechanic who does not normally work on german cars. the problem it had was the fuel line busted and timing was two teeth retarded. i didnt know about the fuel line till after i got it to the mechanic....i just stalled at an intersection and had to push it.

This is whats done/working:
fuel line replaced
timing fixed
compression test OK
injectors are pulsing OK
spark is working OK

car turns over but will not combust and run. sounds like no fire. i would imagine they put the distributer cap on right side up, but that's all that i can think of. if its getting spark, the only problem would be order of the spark. He doesnt have a computer to plug into german stuff and doesnt want to buy a $1k adapter.

Do any of you have any ideas before i get it towed to another mechanic?

thanks

Andy1212

Are the spark plug wires correct in the correct order?

M758

The cam is not 180 deg out of phase is it?

Tinker951

I think it is more likely that the plug wires are in the wrong order than 180 deg phase shift. i say this because the cam was only 2 teeth out of time when it was running, i would hope he didnt turn it a full 180 to line it back up. but then again, i would hope that the plugs were in the right order, too. btw, i'm thinking its the plugs, too and i'm going by the shop first thing in the morning to look at the car myself.

jstand22

get a new mechanic....if he doesn't normally work on German cars why is he starting now? Take it to a Porsche wrench.

CPR

951?

Go straight to the sensors...do not pass go. GO STRAIGHT TO THE S & R SENSORS>

944Ross

I can't believe the car was running OK, with timing two teeth retarded? I'd be suspicious of how this was determined to be the case. So did he loosen the timing belt and move everything two teeth, or what? Likewise, what is "good compression"?

Tinker951

S and R? If there were a porsche shop around my town, i would definately take it to them. the best i can do is take it to someone that doesn't work on tractors all day.

Whisper

Well, speaking from experience, a 944 will run with the timing two teeth retarded.

It will not, however, run anything like "okay". It will feel weak and sluggish, especially in first gear.

CPR

T,
Is it a 944 or a 951?

944Ross

S & R = Speed and Reference sensors

Tinker951

i had just replaced the cam tower gasket, and i had a hunch the timing was retarded when i put it together. the red line on the cam gear didnt look the same spot as when i took it off, but it was still in the hole. the crank never moved so i felt it ok for the time being. there was a definate loss of power with retarded timing, but not so bad that the wheels wouldnt slip out from behind in second gear on full boost. i dont know the exact measurements of his compression test. he was mainly looking to see that a valve wasn't beat up from interference of the timing.

Tinker951

951

CPR

Nevermind, I just re-read your entry. A 951.

At the rear of the motor, near the center of the firewall you will find the wiring harnesses for your speed and reference sensors. If these are not reading you will not get a spark. They are notorious "gremlins" in the turbos...not so much in the NA's from what i understand. Make sure they are plugged in completely. Move them around slightly and chances are it will fire.

Ask me many times how I know....and many other turbo owners as well. If this remedies the issue, drive it to a Porsche mech. and have them replace the sensors AND the wiring harnesses.

knfeparty

^^ The connectors for the speed and reference sensors also love to break and come undone.

I am also very suspicious of the timing deal...changing even one tooth on these cars is a huge adjustment and will cause them to run way out of tune. I think being a few (4?) teeth off will cause valve/piston collision...

I hope you are aware that these are interference engines and if the timing is messed up (by your mechanic) then you will destroy all your valves and essentially total your car.