2000 jeep grand cherokee motor not starting

[jeep00xj]

So my friend has a 2000 grand cherokee 4.7l v8 and a few days ago the timing chain guides decided to explode and the timing jumped. He replaced all the guides and such and set the timing and now its not starting at all. Hes got spark and is getting fuel. We have hit a brick wall on ideas. If there is anyone out there that has an idea on what the problem may be please let me know.

[CSaddict]

Check compression. Is the cam or push rods all bent to shit?

[LittleD]

diff car, but when my vw skipped, it bent all the valves to shit and would crank, but not hold compresson.

[1cleantj]

yep sounds like somethings bent. its pretty common to see things get bent up when timing jumps while engine is spinning a couple thousand times a minute... hopefully the motor is repairable. its hard to find 4.7L in junkyards, the ones they have are high money

[jeep00xj]

Compression is between 80 and 120 on all 8cylinders. Could the cam and crank sensors be out of sync?

[EvilWJ]

I am the onwer of said vehicle. my research and thoughts lead me to believe an issue with my spark timing/ cam+ crank sensors. motor turns spins but does not turn over. Plugs are wet so getting plenty of fuel. After the first try of putting all new timing gear on, it was determined i was 180 off so i turned the cams. before doing so my compression was anywhere from 75 to 120 on all 8 cyl. I believe its supposed to be around 150? so i will do another set of tests with all the plugs out tomorrow and see if my numbers are better now that i turned my cams. but regardless, the motor still wont start. dots on chains line up with sprockets, v8's on cam sprockets are at 12, idler at 12 and crank at 6. I could do a leak down test to check for bent valves, but I'm getting no knocking or tapping of any kind when the motor spins, and i am getting some compression. I am at a brick wall and lookin for any help.

[EvilWJ]

Just ran more compression tests. 145-155 for the front 5 cylinders. Didnt have enough light left to get the back 3. plugs still soaked. ASD sensor looks clean. After researching this issue for hours ive found others having this same issue of a no start after a teardown on this motor. Someone has to have some advice!

[LittleD]

have you checked the cps at all?

[EvilWJ]

Ive pulled it and looked it over, it looks ok. but I'm not left with to many options other than the cam+crank sensors and the notched wheels or my ecu. Someone told me that since my motor ran (just really horribly) when i pulled it apart and it was off timing then, that my cam and crank sensors were obviously getting off sync readings and it threw off the programming on my ecu. If i have compression on even one cylinder, and im getting the fuel+air mixture, I should at least be getting a pop. All the motor does is turn. the only explaination could be that the spark isnt happening at the correct time?

[clean4drxj]

are you sure your timing is correct

[EvilWJ]

I am 99.999999 precent sure. It doesnt even backfire, make a puff, nothing. motor just spins over. even with a spray of starter fluid. same when it was 180 off. Which must mean a spark issue right? I tried a new cam sensor, changed nothing. pulled the ecu out and it changed nothing. So I am to assume my ecu is not doing anything 'ie' not giving me spark+fuel timing?

[DrThunder]

Have you checked for spark? Simplest test ever

[EvilWJ]

yes i have, i did have spark a couple days ago, but i just tested it again and now i dont... doesnt mean the spark timing is correct anyway. plugs are brand new, all coils and grounds plugged in. From all the research ive been doing and the symptoms im having, I'm leaning towards my computer needing replacing/reflash. ive found multiple people having the same issues after a rebiuld on this motor...

[doubleuj17]

If the chains jumped more than 3 teeth it will bend the intake valves,its an interferance motor,you can pull the head and valves,check the guides for any damage and if ok,you can just lap in the new intake valves and it will be ok,i've done a few this way and never had any problems as long as the guides had no damage.

[jeep00xj]

he already replaced the guides.