88 xj Bucking and hesitation

I have an 88 xj, manual. I just got it back after have a second hand stroker installed. The first couple times I drove it, it acted fine but the timing was off, so I tried to adjust it, and it hesitation seemed to get better, there was pretty much nothing at all. I went a drove it yesterday, and it was fine until it warmed up, then it would stall and buck, but only in second gear and up, the more throttle you give it, the worse it gets, but when you push in the clutch, the motor stills has a hesitation when revving. When acceleration down the road you can feel the power start to kick in then give out, so on and so on, and it backfires through the TB. Do you think its the timing or could it be overheating ( i have idiot lights, cant tell). Any ideas?

Any Help?

Could be a fuel problem, too little fuel or not enough fuel pressure, or an ignition problem.

Sounds like a fuel delivery problem. Check the fuel pressure with a pressure gauge and check the fuel pressure regulator operation by removing the vacuum line on the fuel pressure gauge for a few seconds. If pressure is dropping during acceleration or when you press the throttle I would replace the fuel filter, then the fuel pump if its not the fuel filter, but don't do either if the fuel pressure is steady with and with out the vacuum attached. Should read 39 lbs with out the vacuum line attached and about 31 lbs with it attached.

If you elliminate the fuel as a problem get a $10 multimeter and a Renix FSM and start testing the ignition sensors and wiring for bad parts before you buy or replace anything. Too many potential bad parts to replace them with a hit and miss trial and error method. A $10 Multimeter can save you $800 in parts costs trying the old guess and replace a part "multiple choice" game.

I went and got a distributor at the local u-pick and installed it today. Still had the same problem, a few days earlier the battery lost charge, soo I went to go jump it off soo that i could sea-foam it. I put the sea foam in throught the vac line and let it sit, when i restarted it i was giving it small revs to blow all the junk out, at first I could put it down to about half throttle without it hesitating and bogging out, but it kept getting worse for the next ten minutes, if i even touched the gas it would almost die out, it eventually did. Soo i jumped it off again and left the jumper cables connected and it was perfect, good throttle response no bogging or hesitation. The battery in the xj is about a week old, soo i assumed it was the alternator, pulled it out and took it to advanced auto. They tested it said it was fine. Whats my next move? wiring? fuses? I looked throught the hanes, it was like jiberish to me.

AD-8 said:

I went and got a distributor at the local u-pick and installed it today. Still had the same problem, a few days earlier the battery lost charge, soo I went to go jump it off soo that i could sea-foam it. I put the sea foam in throught the vac line and let it sit, when i restarted it i was giving it small revs to blow all the junk out, at first I could put it down to about half throttle without it hesitating and bogging out, but it kept getting worse for the next ten minutes, if i even touched the gas it would almost die out, it eventually did. Soo i jumped it off again and left the jumper cables connected and it was perfect, good throttle response no bogging or hesitation. The battery in the xj is about a week old, soo i assumed it was the alternator, pulled it out and took it to advanced auto. They tested it said it was fine. Whats my next move? wiring? fuses? I looked throught the hanes, it was like jiberish to me.

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Well on an 88 the voltage regulator is in the alternator, so yes it is time to check those battery cables, alternator cables, ground wires and connectors, fuses, fusable links and possibly even the ignition switch for a bad connection. Some bad wiring or connectors/terminals is not unusual for a 19 year old XJ. I should know I have three of them now, but I love doing wiring, LOL.

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