Strange 944 Running/ No Start Issues....
 

Hi everyone, starting a new thread to make it easier for everyone trying to help me out with my 944 problem. I've made some headway on solving the problem but keep running into road blocks. Id like to thank everyone for their time and their suggestions both on this thread and on my previous one. Let's dive in.

'83 944 is showing severe signs of over fueling. Smokes horribly (black carbon soot), CO levels off the charts, Fumes eye watering with heavy raw fuel smell. Oil being diluted with gas. Car will sometimes run and drive perfectly or will stall at any given moment without warning. My plugs are carbon fouling left and right. Most of the time my car refuses to start. It will just crank and crank and crank. to avoid flooding I do not step on the gas when trying to start. However if I do the car starts and runs terribly on perhaps 2 or 3 cylinders. Other times the car starts and runs normally until it either develops a misfire or dies completely.

Here is what's strange. During a no start if I remove the fuel pump fuse and kill the pump, the car starts and runs. As soon as I replace the fuse the car dies.
If the car manages to start under normal conditions but runs bad and idles rough, it smoothes out once I disconnect the AFM. If I try connecting the AFM the car stalls and dies.

Here is a complete list of everything I have tested and replaced.

Replaced:
Battery
Battery ground cables
Starter
spark plugs (5 sets in the last 10 months)
Oil (3 changes in the last 10 months)
Fuel Pressure Regulator
Fuel Pump
Fuel Filter
Added in car fuel pressure gauge
Ignition coil
Intake manifold gaskets
Fuel Injectors 3/4 are replacements for my originals. All have been sonically cleaned and flow tested.
AFM replaced with a tested good unit.
Coolant temperature sensor (for DME not gauge)
AOS Seals (car was leaking oil back up through the intake. leak has stopped since replacement.

Test results:
Fuel pressure within spec, 29 psi running, 32 psi car off pump jumpered.
12 volts at the pump when cranking. Zero volts when fuse is removed.
Speed/ Ref Sensors. (ohm output within spec)
Wiring harnesses for injectors, AFM, TPS, Coolant TMP, Speed/ REF sensors, Checked for continuity/ shorts.
TPS tested via clarks procedure.
Timing, all timing marks line up perfectly, belt is in good condition.
Oil Pressure builds when cranking. Normal when running.
Spark, Each plug was removed and grounded to verify spark
Cap and Rotor were inspected, both in good condition.
Grounds checked/ cleaned.

Im not really sure where to go from here, the car is still showing these symptoms. car was my daily driver for 2 years. symptoms showed up in January. All parts replaced one at a time systematically after troubleshooting. others were just preventative maintenance.

Hi Jacob! Sorry to see you're still after this one :(

I'm wondering if your motor is worn out to the point of not sufficient compression? Maybe your "over-fueling" is simply mixture not burning thoroughly. I know.. it's the last thing we'd like to admit possible

How do you know the DME is good? A bad temp sensor in the AFM can cause all sorts of grief, even if it works fine in other respects. How about the DME? If you loop checked each circuit, did you also check to insure there are no shorts to grounds, or other circuits? Make NO assumptions.