Happy Summer! I own a 2000 2.5L Chrysler Sebring Convertible, 95,000 miles. Ongoing issue for 18 months: Car hesitates (misfire) after 15 minutes of driving, when accelerating. Can Cruise just fine at or below 50 mph. with minor hesitation.
New timing Belt, distributor (OEM), Timing belt rechecked (3 teeth off), sensors etc. Since those were done and checked, perfect power, acceleration, smooth...Till the "misfires/hesiataion occurs".
Found a Mechanic who was willing to spend time with it if the timing belt and distributor did not cure. He has been true to his word and just spent 5 days checking it over and over for any solution. Codes were coming up as MISFIRES on all 6 cyl after reaching a warm temperature and/or over 2200rpm while just accelerating without the actual "LOAD" of being on the road. He checked all possibilities and came up with this diag:
"I'm 90% sure its the computer". UGH.
I have spent over 2 months researching this issue and have found the "PROBLEM" to be real in several of this model, but that's where the discussion ends (bad catalytic/clogged/egr/distributor/timing/crankshaft positon/throttle position,new plugs/new wires/fuel filters/fuel pumps..
Several folks have replaced EVERYTHING but no fix. If there was a fix, unfortunately, no one has ever posted what did work....NOT ONE POST OF A CURE. Could MY plea for the ANSWER be here on this forum?? Will Trump be our next President? I kid, I Kid....Should I try the computer with a flash, or just be happy I can put the top down and travel the beaches but never going over 50mph again in my convertible, thanks again everybody!!

 

I would try the fuel filter next. Many years ago, my dad's 1960 Dodge 361 V-8 exhibited symptoms like that: Would run fine for short trips (he drove it to work every day but only about 5 miles on surface streets) but when I borrowed it to drive 20+ miles on the highway, it would stall out while going 55 mph. Replacing the fuel filter cured the problem. It could easily handle slow speed driving but got fuel-starved at high speeds.

Your convertible is now 15 years old and since the fuel filter is built into the fuel pump in the tank, it's not something that will get routinely changed and could be as old as the car. It's a pita to change since you have to drop the fuel tank to to it but I would do that before replacing the computer. What ever you wind up doing, come back and share the results here so maybe somebody else can have the benefit of both your successes and failures.

 

Should I replace the fuel pump while the tank is dropped too? I really appreciate your feedback and YES, I will let you know what happens!

 

Price out the job with and without the fuel pump replacement and make up your mind based on available cash and the amount of confidence you have in the old pump.

 

UPDATE: Nothing new. I wanted to let whomever maybe having this issue know, I have not moved any further than my original post. The car has moved just fine, over 300 miles at 24 MPG and it's cool, just haven't been over 55 mph and/or the hesitation is just there from time to time. I don't have anymore $$$ to feed this beast. Please post if anyone has a new idea that may have worked. Thanks!