Hello all

I have a problem after an engine change. I swap the engine from my 98 xj to my 99 xj.

Bolt are sport edition 4 doors with auto.

Everything went well exept that now it does not want to start.

At first the engine turn but did not start. Now it turn for one or 2 turn and does a loud sound in my exhaust and the starter disanguage from the fly wheel and turn freely.
It sounds like the explosion happens when the exhaust valve is open.

It seems the timing is way off but when I swap the engines, I did not touch the distributor, the cap and plug wire.

What could it be?

There is fuel (checked the fuel rail).

I'm loosing patience.

 

Swap all the computers, PCMs, and ECMs and associated wiring.

It is my understanding that 99-01 are the same, but different from 1998 and earlier.

 

Even if I swapped all the accessories from the 99 to my 98 bloc.

The only things from the 98 that I swapped is the engine (long bloc, head, valve cover, the water pump and the fly wheel).

All the rest is from the 99. The intake and injector are 99, TB is 99, starter, alt. and trans (with torque converter) are from the 99.

 

From what I have read '98s are different than all the others. It got improvements over the '97s. I didn't get the down grades that the '99s got. It still has a distributor, and not the weak coil pack head. That alone means use need to swap everything.

 

My 98 and 99 both have the distributors, the coil pack came in 2000.

Both block are the same, that is why I dont understand what the problem is.
Everything work fine in the truck, gages, lights, radio, etc.

 

You might have stabbed the engine wrong. It may not be square with the transmission/engine, causing the starter to disengage from the flywheel ring gear. But that's a long shot.

But it may not be a hardware problem.

As I said earlier, it may be differences in the computers/electronics.

Good luck.

 

Did you mess with the flywheel? The CPS reads 3 sets of teeth on the outer rim of the flywheel, to know when to trigger spark. If you had the flywheel off, did it go on right?
Check the timing with a timing light. (You need to remove the electric fan to be able to see the timing marks). Not concerned about being a few degrees one way or the other, but verify it's reasonably close to TDC.
Double-check the sparkplug wiring from the distributor. Then triple-check it. I know you said you didn't mess with it - did your helper? Firing order is cast into intake manifold.

 

The fly wheel in the truck is the one from my 98 and I checked the parts # for the 98 and 99 and they are the same.

I did not removed the fly wheel from the engine and it was running fine in my 98. Could it be the CPS that is dead???

I think that I will try to swap the distributor and will install the one from my 99.