'88 Carrera Won't Start...

[dpilotpaul]

I recently broke my 911 free from its garage prison. The car had not been driven (or started) for about 7-8 months. Pretty sad. I had to jump start it to get to run but once it started it ran fine. I then took it out for a spin around the block and it died. It probably made it about a mile before quitting. After doing a lot of reading on this and other sites (thanks for all your expertise), this is what I've done so far:

Changed the DME relay

Changed the fuel filter

Pulled a plug to check for spark (it does)

Changed the battery

I have jumpered the fuel pump fuse and can hear the pump run when the ignition is turned on. The pump doesn't run without the jumper in place. There was fuel in the old fuel filter when I changed it. I also get a little fuel seep from the upper fuel filter (the new filter) fitting when the pump has run. Perhaps a little back pressure from a blockage? The plugs looked fine when I pulled them but they were dry. I think that somehow the gas is not getting through but don't know the next step.

I'm a little confused about the pump. Since it doesn't run unless jumpered and then the car still won't start, could there be some sensor signaling the pump not to run? Any help would be greatly appreciated. I'm no expert mechanic and haven't tinkered with this engine at all. I do, however, take instruction well (married for,a few years now...).

[Synchro Joe]

Check the connections on the cylinder head temp sensor? Mine would not start, but turned over and had spark, gas, etc. During a visual, noticed the little white plug was loose of the sensor connection (also needs replacing), reconnected and that cleared that fault. Just an alternative. In the left side of engine compartment opposite the fuel filter on the right, three connectors, bottom two are for speed and TDI sensors.

[dshepp806]

We recently learned a good no start lesson as to DME relay female socket-side connection integrity. Time to go through the no-start checklist. Check every connection at first..

Best!

Doyle

[rick-l]

Originally Posted by dpilotpaul

I'm a little confused about the pump.

The pump will only run with the key in the start position or when the DME thinks the engine is running.

Did you see if it would fire on starter fluid?

[dpilotpaul]

I'll try the starter fluid again. It seemed to work during the initial troubleshooting. I'll check the CHT sensor as well.

Could clogged injectors send a signal to the DME to keep the fuel pump from running? That might explain the fuel pump not and the no light off when it's jumpered... Any experts? Thanks.

[rick-l]

Originally Posted by dpilotpaul

Could clogged injectors send a signal to the DME to keep the fuel pump from running?

No

A shorted injector will disable them all however but that is not where I'd start looking. On the other hand pulling the connectors one at a time and seeing if it starts is simple enough.

If it coughs on starter fluid, based on previous threads I'd buy a pressure gauge at Harbor Freight and a Noid light.