Ben Allison

Have you tried jumpering the FI and fuel pump circuits (instead of replacing the relays)? Might be worth giving a try. Remove the relays and jumper 30 to 87

86'928S MeteorGrey

Are the plugs wet with fuel? If not, maybe the injectors are clogged. You need to know you are getting pressure at the fuel rail. If you are getting spark at the plugs, and pressure at the fuel rails, pull the injectors and clean them, or send them off to be cleaned. Maybe when you did the fuel pump/system parts replace, debris in the lines went to the injectors. Try unplugging and blowing out computer connector, and reconnect. I've had very light corrosion there give me ignition headaches. If all this fails, maybe a local member will alow you to try their computer for a quick test...

Good Luck! Dont give up! You'll be driving in no time!

fomanchu

J.Kenzie(Dave),
Im ordering a fuel rail gauge from 928 Rus tomorrow.

Ben,
I bought new FI relay, but will try to jumper both fuel and FI. I have lights on noid from injector, so I didnt think jumpering FI would help...

MeteorGray,
I have cleaned the Jetronic computer connector too...
Thanks!

j.kenzie@sbcglobal.net

Look closely at the FI relay, it has a diagram of its pin layout. While it is very unlikely that a new relay is bad, you need a Y-shaped jumper for that relay. I think it is 30 to 87 and 87A, but check the diagram.

fomanchu

Yeah..I think ur right on the FI relay jumper..just need to make one and test! Thanks!

Ben Allison

If the jumper gets it going but the relay does not, then you'll need to trace out where 85 and 86 go to and make sure there's not a break somewhere.

fomanchu

Installed the fuel pressure gauge and turned the switch to the on position (primed pump). Pressure was at 40 PSI .. but dropped like a rock in less than one minute. I tried starting it (cranking) and I got the same results. While reading the Bosch FI Mgmt book, Im kinda confused as to what to test next..cold start injector or fuel pressure regulator?

Ben Allison

Pinch the regulator return lines (there are two) and see if the pressure stays up. Vice grips with a rag (to keep the teeth from chewing up the line) work well as a clamp. If the pressure stays up, you can remove them one at a time to determine which regulator is bad.

If that doesn't help the situation, then it's on to the cold start injector. You can pull the plug on the cold start injector to see if it's perhaps shorted to the on position. Unfortunately it's a metal line so you can't clamp it, and since it's integral to an important fuel artery, you can't disconnect it easily, either

Ben Allison

Also, try jumpering the fuel pump relay if you havn't already ...

j.kenzie@sbcglobal.net

Great idea on clamping the fuel return lines. I hope this helps or other experts can chime in. I think you are getting close.
Good luck

fomanchu

Great and thanks! I will try both methods today. I really appreciate everyone's help and input!!

fomanchu

Update...Well I diagnosed a bad fuel pressure regulator, order two and installed along w/new fuel hose w/clamps. Fuel pressure now takes about 30-40 min before it drops to 14psi as per WSM. But the cars still cranks sputters and dies! I pulled plugs and i can smell gas, noid light flashes, my battery is fully charged (new and on maintainer), I have spark (spark plug tester) and fuel pressure (as per Roger fuel gauge).. so now off to check timing. Any additional thoughts...??

Ben Allison

if you start the car with the throttle pedal partially depressed, does it rev up and then die? or does it continue to sputter near idle?

fomanchu

Ben,

If I step on the peddle it continues to sputter and then die. Also, I just check the air flow meter and its within specs.

Update..I just re-read ur post. I havent tried to start with the peddle partially depressed. I will try now and update.

fomanchu

Ben,

THe cars still sputters and dies w/a partially depressed gas peddle.