I have a 1999 4.0 Manual Transmission TJ. I can't get the the vehicle to start. The ignition side has spark and the color is red to orange. I placed a noid light on the injector side. I get one flash on the light and then it goes blank. The vehicle will not run on starter fluid. Fuel Pressure at rail is 47 PSI. ASD? Computer? I recently have been spilling fuel every where. Can't find the leak! The Code I have been getting is P0172. (EVAP system did become dislodged from tank. !_Fixed the hose.) Recent changed out injectors to ones that engine was tuned to. Was running rich and would only run well at wide open throttle.
Injector not pulsing correctly. Ignition firing correctly. No start even with starter fluid.
- Thread starter g1999TJ4.0strokedto4.7
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JKP
TJ Addict
You don't have good spark and/or properly timed spark if it won't run on starting fluid. Your spark should be blue, so I'm going to assume it's weak since it won't fire starting fluid.
Spark is timed off the crank sensor.
Injectors are timed off the cam sensor in the distributor.
Spark is timed off the crank sensor.
Injectors are timed off the cam sensor in the distributor.
Recently I've had to put a button put a button in side vehicle to have the ability to start the vehicle. Unable to jumper relay to get vehicle to start. Pulled fuel injectors off and watched them inject fuel. Watched for spark It was red. Ohmed out ignition coil and it is with in parameters. Wondering if it is the ASD circuit? Don't know what to do?
JKP
TJ Addict
Your spark is weak.
Take the wire from the coil and test the spark directly from the coil. If not blue, coil is shot.
Take the wire from the coil and test the spark directly from the coil. If not blue, coil is shot.
Did a recent tune up. Newer wires, changed plugs to champion iridiums. Cleaned up cap and rotor. Rotor turns. Put in new crank position sensor. Tachometer still doesn't move when turning over starter. It seems like I'm getting enough fuel to the rail. 47 psi. I don't know what to do. Thinking about putting in a new fuel pump assembly. Going to pull each spark plug and see true color.
That's a classic sign of a bad crank position sensor (or wiring to said sensor or another sensor shorting it to ground.)
-Mac
Pulled all the spark plugs. The color is orange on all spark plugs. All plugs were dark black. Too much fuel. I will see the color of spark coming out of coil tommorow. Ignition coil is only a month old and I ohm it out and it seems to be the same as a brand new one off the shelve. I have a bad valve train. I got a code P0172 on 11/5/24. This Youtube video seems to make sense,
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Replaced fuel pump assembly. Replaced engine harness with a used one (same results.No start, Injectors injecting fuel 49 psi. Spark 40000 at coil. Orange color. Still can not get the tachometer to move even though I have replaced the crank sensor. Starter still does not work without hot wiring it. Lights in the dash do not completly work. Put a new exhaust / intake manifold gasket. Do you think i should put a new used wiring harness in the dash? I am lost. Q
Some gauges like battery and fuel works. Engine did start working last week but only from 3000 - 5000 rpm. Now I can not replicate it. Computer !....
Yes new crank position sensor. The engine seems to sound really good last week when it turned on. All the sudden blue spark. Had to keep it above 3000 rpm.
Might need an ocilliscope or a scanner with one built in.
Verify 5v bus to the sensors and off the PCM.
-Mac
Verify 5v bus to the sensors and off the PCM.
-Mac
SO I SHOULD TEST FOR 5 VOLTS. BLACK power control module C1 has A22 PIN A14 14RD/WT FUSED B(+) . GREY POWER CONTROL MODULE P
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