Porsche Repair: restarting 944, fuel pressure gauge, plastic filters

Question
Hi Dave, hope that you can help me out here.
I have a 1989 944, even though I have not been driving the car since last year, the summer to be exact.  I have not been able to get it started.  It set for a while with very little gas in it.  After charging the battery the car turns over but barely starts.  I am recharging my battery tonight so that I may try it again this weekend.

Answer
Hi David,

It seems odd that after only one season you'd get Crud, but maybe it's actually true.  Crud forms in the gas tank's bottom when gasoline dries out.  Unfortunately, it also forms in low spots in fuel lines, or worst of all, in your tiny, but very expensive fuel injectors.

I'm going to assume the gunk, or crud, is limiting the required fuel pressure because a line is clogged...and if junk or gunk got into the tiny, tiny orifices of the injectors, the car would barely run.

I'd start by replacing the fuel filter, but not till you "prep" the lines.  If you replace the filter with one your local auto parts store will $sell$ you, you might as well buy two.  The first filter installed will be contaminated and ruined too quickly...so, replace it with two much cheaper clear plastic filters, also available at the local store.  You won't feel any pain throwing them away when this is all over.  Buy extra fuel line and run the line so both clear filters can be easily viewed while the engine is cranking and running.

You'll either see the filters catch debris and the car will begin to run better...or, the fuel will be clear and the car will begin to run better...or, the car still won't run and the injectors are suspect.  You'll want to avoid taking the injectors apart, so try to get them clean and free-running by using fuel injector cleaning fluid...at a pretty good ratio in the fuel tank.

Re-charge the battery while you add a temporary fuel pressure gauge to the fuel line just before the fuel gets to the injectors.  Test the pressure while you keep starting or trying to start the car...moving the cleaner through the system.

Write back to me with your progress.  We'll want to really ponder the next steps if you can't get the injectors clean this way.

Dave