My 1988 jeep cherokee I6 takes little bit to start. Also, once it cranks the rpms go almost up to 2000 then eventually go back down. I was thinking spark plugs would lag the starting so i changed them and the rodar and cap but that didn't improve the starting. But, whenever u changed the o rings on the fuel injectors it started right up the first couple times it cranked then went back to normal, does this mean i need new injectors?

 

Sounds like a fuel delivery issue to me... Have you tried changing the fuel filter?

 

Assuming you have an electric fuel pump in the gas tank, then try a "Poor Mans Prime."

Turn the ignition switch on several times w/o cranking. This will fill and pressurize the fuel system. Should start after the prime. If it does, then the "cure" is a new fuel pump.

 

Yours is a Renix XJ, just like mine...

Our system is known to have ground issues. Clean and freshen all ground wires, particularly the one the neg batt cable goes to on the block.

The Renix won't start injecting fuel until it sees 300 rpm, and if the grounds are bad the starter will be weak adding to the already notoriously long Renix crank time.

Also check and adjust the TPS. Renix XJs are known to have tps issues, they need adjustment every so often...