Cranks over but wont fire it is blowing back through the intake?

ANONYMOUS

MEMBER
1999 JEEP GRAND CHEROKEE
101,000 MILES

I have a jeep with a 4.0 that I just installed a used motor in that I got from a yard. The jeep ran when the pulled the motor bot the stripped everything off the motor. So we ended up moving all the parts over. We installed the motor. She cranks over but wont fire it is blowing back through the intake. We reset the NOT distributor like 8 times still no go. Will a bad ground cause it not to fire. Or can the flywheel be installed wrong and make it fire wrong. Lost and have no clue on the problem

Wednesday, December 26th, 2012 AT 3:01 PM

1 Reply

BORIS K

MECHANIC
836 POSTS

Hello,

Please check the distributor installation again.
Ensure that cylinder 1 is on TDC, that is Top Dead Centre.
Remove the distributor and remove the rotor and camshaft position sensor
Align the hole in the plate with the hole in the distributor housing.
Lock the shaft in this position .
Ensure that the oil pump drive is lined up at 11-5 o'clock, see below image.

See below link on how to time the distributor correctly.

https://youtu.be/xRHW0i3V6qM

Once the distributor is installed correctly please ensure that the firing order on the distributor cap is correct. See image below.

Please let us know how you get along.

Cheers, Boris

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