tmathews

2000 xj i6
this machine will normally start up and run/idle ok. it seams i do not have the appropriate power that i should have driving down the road i had a 89,96,99 and they all had much more power than this 2000 its gutless. After running a wile get up to temp and shut it off it has a very rough time starting from a hot start most of the time i can rev the engine and it will clear out and run.
Ive changed
Throttle Position sensor
Camshaft position sensor
Crankshaft position sensor
New injectors
New Coil Rail
Temp sensor
O2 sensors
ive swapped PCM
ive swapped TCM
ive been up and down the wiring harness had it all ripped out, cleaned connectors, i have all the connections zip tied to prevent from coming lose.
did a head gasket kit i thought maybe head gasket wich it was leaking a little but replacing did not help.
its been a wile since i checked the fuel pressure i did when i first started seing my issue and i think it was 35psi i was told it was good.
ive taken out all electronics that are not necessary Air bag module, the radio!?!?!?!?! the air conditioner pump and what ever else thats no longer in the vehicle lol...
i thought it was a heat issue with the fuel rail i shielded the rail wired my electric fan to be on all the time even cut a hole in my hood and put a ****y *** hood scoop in.
its been periodically getting worse this is more of a trail truck for me but the past year it hasnt seen the woods at all... today when i pulled the codes off the vehicle i got some weird codes that make no sense shown in attatched picture the throttle position code has been on for the past month wich ive changed 3 times and the O2 code just come back...
Im at a loss.....


i was unable to find any information on them codes my second PCM wich i put in after seing this also thru some weird codes.... 2 bad PCM maybe....

Trey

Just a thought. Are you sure the TPS plug is making good contact or does not have a loose connection?

Turbo X_J

Fuel pressure should be 49 +/- 5 psi. Were all these parts that you replaced actually bad?
ETA:
Was the cylinder head trued up & checked for cracks while it was off? What are the results from a compression or leak down test?

"ive taken out all electronics that are not necessary"
What exactly? and why?????

tmathews

periodically i kept getting fault codes saying there was voltage issues with the O2 sensors with the crank sensor ect ive had multiple codes in the past year i change parts codes come back eventually go away i actually made my own little plug for the TPS with the same codes run new wires changed the TCM because of people having issues with the TPS shorting in the TCM and some sensors were just a throw and hope... i took a new file and in one spot on the head was able to get 3 thousands under it using feeler gauges wich i would think the gasket would make up for 3 thow...

tmathews

i will pull the gas tank off tommorow and take a look at the fuel filter and change the fuel pump my buddy has a jeep graveyard i should be able to find a good one but i really dont think thats the issue but now that im asking for help ill give anything a try...

Roler

That compression test will give you a good idea where you stand with your engine (to answer your first issue, the fact that it feels gutless).
And not sure who said 35 PSI is good enough, its not. The 49 +/- 5 PSI it what you'd like to see.
The difficulty starting when hot, still sounds a bit heat-soaky to me, despite shielding. Assuming your (new-ish) injectors are not leaking down...