timing chain question??????

[jusgasit]

anyone ever had a stretched timing chain on a 2.5 jeep yj engine? if so what were the symptoms? mine will run fine for a bit and then it seems like it somehow gets a lil out of time and when i try to rev past 3k it backfires like sh^%!!!and then out of nowhere it runs fine again.if i hold the throttle just under 3k for min and let it pop a couple times it will start to run fine again and i can rev all the way 5k with no issue.any help would be great!!!heres a list of parts we have replaced fuel pump,fuel filter,cps,cam sensor,coil,computer,plugs,rotor cap &button lol!!
one of you guys has bound to have had this problem before???

 

[89wrangler]

intake gasket

 

[mtmech]

Had that problem with my 4.0 a few months back... Was the tps and/or map sensors... They both were bad on mine at the sametime... Oddly enough... But anywho that's what it's sounding like to me... If it where an intake gasket there'd be a whistling sound...

 

[jusgasit]

not the map or the tps........someone mentioned a wore out dizzy and could be grounding out?

 

[mtmech]

Stupid question.... Did ya make sure the distributor was tight? Meaning it won't spin? Not insulting but maybe it's a lil loose?

 

[jusgasit]

yeah its tight.. and ive checked the timing a dozen times to c if it was jumping timming but seems ok.