i have a 97 Cherokee 4.0 6cly that will start and idle at 750 rpms but wont drive at all with out sputtering and popping and boggs down i have changed almost all the sensors and i swapped fuel tanks with a 98 parts jeep i have. the 97 stopped running about a year ago and sat until i got the 98 for parts then i found the pulse ring on the distributer was broke loose and thats why it wouldn't start i know i should of looked under the cam sensor but i just never did ..i put a new crk sensor, ecm, coil but still cant get the thing to run right i have set the distributer more then 20 times thinking maybe one tooth off but just cant get it to run right the fuel pressure seems good and no vacuum leaks that i can find all thats left is the timing chain being off ..btw when the 97 1st died it was really cold and it started and seemed like it was running on 3 cly so i shut it off and it didnt start again till i replaced the distributer anyways if anyone can think of something else to check i could sure use the help before i do a motor swap

 

How are you setting the timing? I had a problem with one I swapped a while back and at TDC the rotor is just past the number one plug not on it like most motors I've worked on.

 

I had a similar scenario last summer. I went through the same things you did to try and resolve it to no avail.

Take your valve cover off and check your valve springs. I had one that broke. If you can get it to Advance Auto they will put it one a diagnostic computer and can tell you which cylinder has the issue...that's how I discovered my broken valve.

Good luck!

 

i will check it out and see about the spring also i was thinking my maybe cat converter may be clogged there is no emissions testing here so that coming off asap i was told it may cause the same issues

 

i set it by moveing it to tdc then lining it up on #1 post when it didnt work i would try moveing 1 tooth one way or the other but it would just get worse also i have on the last few trys found that there is a hole through the pulse ring and the bottom of the distributer that lines up so i did that way and put the oil pump at the 11 o clock spot and droped it in and it seems to all line up right i think the timing is right it has all kinds of power but if you try to drive it it just sputters and hesitate but it will power brake on payment seems to run better if you just floor it so it seems like the timing is right but something else is off ..the fuel is good .. timing seems good so i am thinking maybe a clogged cat converter

 

ok i think i got it i pulled to front o2 sensor and it ran good so i am pretty sure it is the cat converter i just got it off and it was in bad shape i still havent put it all back yet i need to go get a few parts to replace it but anyways thank for the help