Vennessa

Recently my 1997 Jeep Grand Cherokee started running rough. The check engine light came on. We had the codes checked and it was an 02 sensor at fault. I had expected this due to a cracked exhaust manifold that would confuse the 02 sensors into mixing the fuel on the rich side to compensate. My fiancee tried JB Weld on the crack but it was too large so I ordered a new exhaust manifold. We put the new manifold on yesterday and after reassembling the engine, she (the car) won't start.( We had to remove the intake manifold, part of the serpintine belt, power steering pump, air box, and many assorted sensors were disconnected. These were all put back in place and reassembled before we started it. Replaced the air filter also) We checked for spark and all 6 cylinders are getting it. We are getting fuel to the fuel rail also. Really stumped as to why it wont start. (also the check engine light turned off) It will crank but not turn over. Any Ideas??

ol"blue

Try disconnecting the cables from the battery then holding them together (away from the battery) for twenty seconds to drain any residual charge from the PCM and erase any stored memory in it. Then reconnect the cables and try to start it. When it starts hold it at about 1500 RPMs for about 30 seconds then take it for a good 30 minute drive (if it's running fairly good) so it can relearn the system parameters. Of course you'll have to reset the clock and your radio presets. Post back with your results.
And Welcome to CF.
Dan

huntingman2706217

Also double check and make sure the crank position sensor wasn't broken, unplugged, or wires yanked out... its the sensor on the transmission bellhousing right below the intake... its also possible it fell down between the firewall and block when u unplugged it up on top the intake manifold... so you may not even have it plugged up... gotta feed it back up to the top of the intake on the back side...

ol"blue

Here's a pic showing where the CPS is located.

Vennessa

unhooked the cables and reconnected them. still wont turn over. will try to find the CPS and check it. Thanks!

huntingman2706217

Wont turn over now?

Vennessa

no still not turning over, I found an older post about the same issue. I think it is the CPS. I'm not great at this so it may take me awhile to find it and fix it.

huntingman2706217

Confused... in your first post you said it does turn over?

Vennessa

no it cranks but wont turn over. trying to get a picture up for ya.

Vennessa

so here's the view from the top of my intake. I circled in red the item in question. Is this where the CPS attaches on top?

huntingman2706217

Shoot I'm on my phone and outside working... I can't see it well lol

huntingman2706217

See it now and no... but you should have something plugged in there... IAT sensor if I remember right... it'll be a wire plug female end sitting around the top of the intake coming from the harness... the cps has another wire tail coming from it with a male end... basically plugging to wite into each other... blue showed you where it was...

Vennessa

Can the IAT keep it from turning over?

Vennessa

previous owner wrapped the engine in crap! the manifold was wrapped yesterday, today noticed some kind of foam on the bell housing.trying to find the CPS is not easy. Is it easier to find from underneath or through the engine bay?

huntingman2706217

From under it... almost can't see it... have to feel for it just about lol