Fuel pressure issues (Page 1/1) weaselbeak JAN 23, 05:12 PM First a small preface. I have an 86 GT which I put a N/A 3800 in, series 3 from 2005. Darth topped it off for me with a series 2 intake & such. It has ran wonderfully for a great number of years. Recently I started getting misfires & stumbling, getting progressively worse. Tune-up is good. I suspected fuel issues. I had another 3800 laying around so I swapped out the injectors and it got better, but not right. So i rebuilt them & it got better yet, but still puked a bit under load. Then I bought a new set of injectors, which were not returnable, and were series 3 stuff, 2000 & up. I had to change the wiring ends to use them. Now it's bad, crap under load. I would like to stay with these injectors, they weren't cheap. My question is do the newer injectors require more pressure? I have not yet verified my fuel pressure from the pump . I know It could have been the regulator to begin with. Before I start chasing those issues I would like to know if I'm chasing my tail because of the injector switch? Is the series 3 regulator different than the series 2? Lord I hope this made sense. Darth provided me with a manila envelope with everything he did and used recorded inside, and I can't find it anywhere. It's been over 10 years & I don't know what year wiring harness & ECU stuff he used. weaselbeak JAN 28, 09:25 AM Nobody? I really just wonder what the difference might be between injectors from series 2 to series 3. Gall757 JAN 28, 05:40 PM Send a PM to Darth at Sinister performance. Nobody knows more about the differences in the 3800s.