93 ranger no fire/fuel

[Jwar2]

Hi I'm new to the group I've been searching the forums and have come to a dead end. I have a 93 ranger 2.3 manual trans I am not getting any fire to the intake side plugs, also the fuel pump only runs for a couple seconds when key is turned on and that's it. If I jump the fp relay the truck will start but only run on the exhaust side plugs. I am getting injector pulse. I have replaced the crank sensor with a new one and swaped the icm with one from the junkyard I have removed the pcm and checked for any burnt spots but wasn't any. Also the cel comes on with key and stays on while cranking which from what I have read means it's not getting crank signal. I'm stumped at this point any help is much appreciated

 

[tomw]

The intake plugs do not fire all the time. They are used only in certain circumstances which I have successfully not stored in my brain. The fuel pump running depends on the relay being functional, and, I think, the ECM getting a signal that the engine is running.
The pump is run for ~4-5 seconds to insure pressure in the rail which would allow the engine to start, and once started, it must have oil pressure to have the ECM engage the pump. At least that was what I understood.
tom

 

[Jwar2]

Thanks for the response, the fp relay is good I can get the relay to activate by jumper wire at the test port, also when I tried to retrieve codes nothing happens the check engine light just stays on all the time.

 

[tomw]

If the ECM won't communicate, I would suspect that some one of the sensors or relays is hanging it and, off the top of my head, keeping it too busy to 'answer the phone'...
I would start disconnecting things and see if it changes the results. Things that pop to mind are EGR relay/solenoid, vent control, TPS, EGR, DPFE, O2, ECT, ACT, MAP, MAF, ...
If it will run, then it can control injectors & plugs, and must have the cam &/or crank sensors functional. YMMV. This may not lead to anything, but is worth a try.
tom

 

[97LowRanger]

Vref

it sounds like your reference voltage circuit could be shorting? key on check the mass air flow for a 5v reference im not sure but its likely to be 5 not 12 volts all cars that i know of are 5v ref it should be a red wire also go to your throttle pos sensor and check there for reference voltage