GBitterling

jeep will crank but not start.
noticed when key is turned to run or start there is no reading on the voltage gage or the fuel gage. Put a fuel pressure gage on and no reading. Put a jumper in the fuel pump relay port and get a 49 psi reading.Feel i have an electrical problem but not sure where to look. I keep going thru my service manual but it's not helping too much.

SBpunk

First check your grounds. Sounds dumb but you'd be surprised. Next check your fuel pump relays and fuses. If those all check out then detach the fuel line closest to the front of the fuel rail and crank it with a buddy. If fuel comes out then move on to the ignition system.

This is going to involve a screwdriver and a little bit of a shock. Take the number one plug off and put a flat head screwdriver in the spark plug cable and have a buddy crank it. Its going to shock a little but pay attention to the color of the spark. Orangeish is bad. White is good.

Knock those out and get back to us

GBitterling

I,m am goingto check the grounds. It looks like I have a open circuit someplace as I have no movement on my voltage or fuel gage when I turn the key to the run position. Thank you for your imput. Gary

bamasteeler

automatic shut down relay good??if its not you wont get power to anything in the start sequence

tjwalker

What you describe are "classic" symptoms of a failed crankshaft position sensor. Oftentimes, those two gauges will not work when the crank sensor fails in a certain way.

Here is how to further troubleshoot this. Disconnect the connector for the crank sensor and if your fuel and voltage gauges start working with the crank sensor disconnected, there is smoking gun proof that your crank sensor is shorted.

The connector is on the right side of the engine as you are facing the engine and should be near or slightly below the firewall. If you have to buy a crank sensor, do yourself a big favor and buy a Mopar unit directly from Jeep. Crank sensors are not all created equal.

Keep us updated!

GBitterling

Thanks a lot. I found out I hada bad cam sensor and a broken wire inthe harness next to the injectors. Starts and runs good now. Now my cruise control doesnt work. Now for my next project. Thanks again. Gary