This is my 4th jeep and the 2nd with a 4.0L High Output i just bought it for 800 dollars not running i was told it was a matter of not having it put back together all the way after having the transmission out and serviced. it has many vacuum lines missing which i am working on, but after getting it back together to the best of my ability and 2 trips to pick a part and a few to O'riely i still can't get it to fire.

It has good spark, compression rates 120-150 psi, fuel pressure is hitting 40 psi off kicking the starter, has a new cap and tdc on #1 pistion lines up with the #1 prong on the cap, it doesn't sound like it is breathing as much as it should though this may be the dual exhaust with split headers i just think it would be audible air flow. The spark plugs are covered in fuel and some oil after i cleaned them and reinstalled. Am i missing something crucial Air check fuel check spark check ..... no fire

the closest i have come was a massive backfire while trying to run the compression test. Any ideas ??

 

sounds like ignition timing is off.

 

if the top dead center is at peak on the compression stroke when the rotor connects the cap it should be delivering the spark at the proper time shouldn't it?

 

89 is not a 'HO', it's the earlier Renix and there is an enormous difference in the engine control systems. Which engine do you have? Stock '89 engine?

 

Sounds like timing to me as well, make sure the #1 is on tdc of the compression stroke when lining up timing. Not the Exhaust stroke.

Easiest way to tell is use your finger to plug the hole and have someone turn the crank clockwise slowly until you can feel the air pushing. Then get it to tdc and index the dist.

unhook the battery when u do this, lol

 

Doing a compression test with the fuel relay attached isnt a good idea. Just so you know=D

If it is in fact a HO block someone put in there, it is possible they forgot to put the flexplate on from the renix motor. It also means they had to swap the distributor as the ho and renix are different ignition systems. Could have messed up timing there.

 

Upon some further research it appears i was lied to this jeep does have the renix motor and i am still working on putting it all back together. looking for some help posting pictures as i go.

in the picture below my question is simple. What is this and what does it connect to.

the issue is not in the timing. I am currently pursuing an electrical problem for the starting.

 

That looks like the cruise control cable. Follow it back over to the passenger side and at the rear just up and off the block. It should be hooked to a big vacuum actuator. It'll pop into a square hole in a bracket off the rear of the Throttle Body. I'd take a pic for ya' but I removed the Cruise off my 89' because I don't use it.

Black89

 

Make sure the CPS is plugged in.

Also make sure the ground wires are attached at teh engine dipstick tube stud.