Crank But No Start, 95 Classic

D Chapman

D Chapman

1
Jan 3, 2005
11,746
73
On Kennith's private island
1995 Classic, 3.9L

I've traced this back to the fuel injectors not spraying, I think.

I've got spark.

I have plenty of fuel pressure at the rail.

The truck will start on starting fluid, but will not continue to run.

Trucks has beening sitting about 9 years, so I pumped all the fuel out and refilled with fresh gas.

I understand the ECU controls the injectors, but are there any common fixes on the Classic with these type issues?
 
D Chapman

D Chapman

1
Jan 3, 2005
11,746
73
On Kennith's private island
Any idea as to which negative wire you're referring to? I have two, and both are white wires with a black stripe. The two wires disappear into two different wiring harnesses. Is one for one bank and one if for the other bank of injectors?

At the injector, on the right bank (pass side) I'm getting 11.xx volts with the ignition switched on on both pins.

On the left bank, I'm getting 5.xx volts on both pins.

I'm here alone right now and I'm not fast enough to see if that voltage changes when the engine turns over.
 
R

robertf

Well-known member
Jan 22, 2006
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360
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That's it. I think the other one goes to the cruise control for over rev protection. Or maybe it's that brown relay timer. Either way it's not important. Wrap some extension line around it and your multimeter. Then see if it's got continuity at the 14cux plug. While you have the kick panel off give all the relays a once over for corrosion.

You said you have fuel pressure that's why I think it's that wire. Do you have the actual # with the car off? If you loosen the distributor and rotate it back and forth with the key on can you feel the injectors clicking?
 
D Chapman

D Chapman

1
Jan 3, 2005
11,746
73
On Kennith's private island
Well, the fueling issue is another problem I'm sorting. Not sure if these issues are related. Currently I have the fuel pump relay jumped out. In other words, I have the blue wiring harness connector in the passenger side kick panel wired jumped with a wire. With the relay in place, the pump is not getting power. Relay tested good, but I'm not sure of the issue, yet.

I'll have to download RAVE and find out which pin at the 14CUX plug is the right one.....
 
R

robertf

Well-known member
Jan 22, 2006
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360
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yeah they are related. if you have to jump the fuel pump relay and the relay isn't bad then the ecu is not controlling it. It turns on for a few seconds when powered up, then goes off until there is a distributor magnetic pickup event.

Does your check engine light do a bulb test when you turn on the car? Are the fuses in the underhood box all good?
 
R

robertf

Well-known member
Jan 22, 2006
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360
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sounds like the ecu isn't functioning. you could check for 5v on one of the tps pins to see if its at least doing something. I forget which pin, won't hurt anything if you pick the wrong one.

recheck all the fuses. 14cux is stout, its got a gasketed case and lives indoors. bad ecu is rare
 
D

discostew

Well-known member
Sep 14, 2010
7,733
1,023
Northern Illinois
robertf said:
Sounds like the signal wire from the coil - post to the Ecu is open
Click to expand...

I would look into this a little. That wire should have a pulsing ground when the engine is cranking. As far as a common fix for that wire not being pulsed is the distributor itself.

If that's the case I've had good luck with TRW brand distributors. I've put them in about 3 Defenders.
 
D

discostew

Well-known member
Sep 14, 2010
7,733
1,023
Northern Illinois
here is the schematic. The wire I think you need to look at is the one Robert mentioned. If you have spark but no injector pulses I would check to see the ecm is getting the pulsing ground signal.

The schematic I meant to attach is the second one.
 
J

jims95

Well-known member
Apr 20, 2004
203
1
Upland, California
On your picture, it shows the two (2) inline resistors. Disconnect each one and test for continuity. If there is no continuity, there will be no spark signal to the ECU. I was able to find replacement resistors from Rovers North. Do not run without these resistors, as these are protection for the ECU.
 
J

jims95

Well-known member
Apr 20, 2004
203
1
Upland, California
Also, behind the battery is a rectangular covered fuse panel. There is a fuse in there for the fuel injection. If this fuse is gone, the fuel injection will not work.
 
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