No spark

[dcgoff]

My 95 Grand Cherokee has had a problem for the past few weeks starting and getting poor mileage. Most of the time it starts on the first try, but a few times a week it will take a couple attempts to start it. When you go to start it, the starter engages fine and turns the motor over fine, the engine just doesn?t start. Now it will not start at all.
I?ve checked the fuel pump, it comes on when I turn the key on plus I get fuel out of the test port with a hose hooked up to it. What I don?t have is spark to any spark plug or out of the coil. I also don?t have 12v going to the coil when I try to crank it. I have also changed the ?auto shut off? relay. What else can I check????

[mdwatkins]

My 95 Grand Cherokee has had a problem for the past few weeks starting and getting poor mileage. Most of the time it starts on the first try, but a few times a week it will take a couple attempts to start it. When you go to start it, the starter engages fine and turns the motor over fine, the engine just doesn?t start. Now it will not start at all.
I?ve checked the fuel pump, it comes on when I turn the key on plus I get fuel out of the test port with a hose hooked up to it. What I don?t have is spark to any spark plug or out of the coil. I also don?t have 12v going to the coil when I try to crank it. I have also changed the ?auto shut off? relay. What else can I check????

Sounds like a classic Crank Position Sensor...A bad one would give you these symptoms. Try unplugging it...letting it sit for a little and then plug it back in...doesn't always work but it sometimes does...

[Olt Man]

I would have to agree initally with Mdwatkins on this subject. I've had to go to the darn car wash for a couple of my friends doing a spick and span job on there motors. They were completely not aware of the location of the Crank Position Sensor and coated it; and therefore no spark. To actually get at it; you'll need a 2ft extension to get it out and "gently" clean off the optical face.

[dcgoff]

Thanks for all the help. It was a crankshaft positon sensor.