930 won't start HELP

[ChrisBennet]

I'm helping my buddy get ready for a DE tomorrow and his 930 won't start. Here's what we know...

We have spark
We have fuel ( to the point of flooding probably).
Was running before but rough, so we changed out the plug /distributor wires and now nothing.. but all plugs do have spark..
Ideas????

[rsrfan]

Check for vacuum leaks. Intercooler seals are often suspect.

JP

[Rob 930]

Chris,

I know you said you had fuel, but...

Make sure you have the overboost safety switch (which cuts the fuel pump power above 1.2 bar), properly connected. It's located on the IC, right next to the boost pressure gauge sender. If there's any question, just ground the wire to temporarily bypass the switch. It can fail (or people can fail to reconnect it) and it will prevent the engine from running.

Other than that, the only ominous statement is that you changed the plug wires, which raises the ever-present possibility of scewing up the old 1-6-2-4-3-5. But you've already triple checked that, haven't you?

Rob

[ChrisBennet]

Rob, thanks yes we have.
I"m taking off the innercooler and re-installing it now..
Already checked the fuel cut off switch.

[ChrisBennet]

No joy, neither worked, confirmed AGAIN that the fuel pumps and injectors are working, all connections to the innercooler are good

[Garen]

I had a similar experience. Since you say the ignition is ok, then it's probably not the CDI unit. My car had a faulty connection to the "speed sensor", a little box located under the driver's seat. Check the wires at the connector, and also the unit for good measure. The car behaved the same way as when the CDI would intermittently quit. Good luck.

[9dreizig]

More info. I have an MSD and has been working fine. Looked at all the sparks on the scope ( look good).
Oh I was using Chris's log in as he's helping me.
T

[hobieboy]

Not sure if it would affect things but is the BOV assembly doing the right thing? Its supposed to bypass air back to the intake only when throttle plate is closed (i.e. vacuum).

[9dreizig]

Ok putting in new plug wires and plugs .. we'll see what that does.

[Jim2]

Had mine flood pretty bad a couple times, and you mention that it's got fuel "to the point of flooding" They seem fussy if they flood a bit.

Pull the fuel pump fuse(s) then start it and see if it cleans out then dies of starvation.

Jim

[POVI]

Hey guys .. dont forget
I'll have my 930 at work tommorrow, in case you want to drive by and borrow it to swap parts .. to narrow problem down
think of my 930 as a rolling and registerd parts bin

Also make sure you have the air bypass lines connected to the bypass valve (goes to right side of intercooler ) ..that burnt me once

give me a call at work tommorrow, I'll be there @8am

Thanks.. do worry we can figure it out !

Joe

[9dreizig]

Think we've got it licked. I discovered that the green distributor wire was chafed through the outer insulation. That shouldn't matter (one cares if the outer grounded shield touches ground?) but just in case I put a piece of clear tubing over it to keep it from touching anything.
I also replaced the spark plug wires with new ones. I didn't test the green wire "fix" before installing the plug wires (pressed for time) so who knows what part was at fault.
-Chris (the real one)

EDIT: Ooops, Todd was still logged on to Pelican with my laptop.

[ruf-porsche]

SO what happen?

Was it the green wire?

[9dreizig]

Sorry guys, here's the update.. It wasn't the green wire. It appears to be a stuck cold start valve. We disconnected it, and it started right up ( apparently had been flooding). However it is still running really ragged under boost ( that's another thread... Indications are it's still an electrical problem or perhaps wastegate ?? I'll keep you posted. I've been really busy with travel the last few weeks that time has been limited. Hope to jump in again this weekend.