Loss of injector pulse

giltgy · 05-20-2018, 08:33 AM

I am battling a no start with my 85.5 944. No fuel, failed noid light test(valid???) good spark fuel pressure tried some 14.6 ohm injectors wondering if I damaged the dme doing that?? Am going to put a scope on the sensors next check if they are “really” good since they passed voltmeter tests. If sensors pass with the scope the dme will be next for service or replacement. Best place to send for service on the dme??? Anyone know if the Rogue Ecu is sequential type ????

Jimmytnap · 06-17-2018, 03:57 AM

Following. I hav no fuel delivery or spark with car cranking. Fuel pump delivers fuel jumps directly to battery. DME replplaed no help. Followed Clark’s garage tests. Could get fuel pump started by jumping DME but now that’s gone Help appreciated

djnolan · djnolan's Garage

Are you getting spark when it is cranking?

Bradical · 06-18-2018, 08:38 AM

If you have no spark/fuel during cranking but you get fuel pressure when you jump out the relay then I would look at the ignition switch.

DannoXYZ · 06-18-2018, 09:05 AM

Quote:

Originally Posted by giltgy

I am battling a no start with my 85.5 944. No fuel, failed noid light test(valid???) good spark fuel pressure tried some 14.6 ohm injectors wondering if I damaged the dme doing that?? Am going to put a scope on the sensors next check if they are “really” good since they passed voltmeter tests. If sensors pass with the scope the dme will be next for service or replacement. Best place to send for service on the dme??? Anyone know if the Rogue Ecu is sequential type ????

Using hi-impedance injectors won't hurt DME.

When scoping the sensor-signals, verify they have required peak-to-peak voltages. Verify sensor-spacing of BOTH sensors, figure-8 washer makes difference.

If both sensors within 0.8-1.5mm and peak-to-peak voltages out-of-spec, then yea, replace sensors.

giltgy · 07-03-2018, 06:37 PM

I have just found a dead short on one injector lead. In my haste I forgot to tape solder joints, and shrunk wrapped two wires together. I checked harnes with DME unplugged, checked okay. I checked for injector pulse, and believe that having attempted to start with a short, I have damaged the injector driver. Is this a likely effect of a dead short on one injector lead???