Okay I really need help here because neither my brother nor I know what the freaking issue is here..I'll try to include everything that has happened here and to answer any questions in advance.

Recently in the last week my brother and I rebuilt my 383ci LT1 up in Ohio, to start the engine and listen to it run is like when heaven ( NO ISSUES!) no skipping,chugging,vibrating nothing! getting it on the road heading back to Albuquerque it would roll through 1st and 2nd gear no problem but when going through 3-6th gear at around 1450rpm it would chug twice and then I would loose acceleration until the rpms would go back down to 1100 and then the throttle would come back.

To break this down a little bit more while on the highway in 6th gear at 1450rpm's I am going 65mph at 66+mph I loose throttle until I go down to 59mph or 1100rpms IF I push in on the clutch I get throttle back for a second and then it chugs twice and then no throttle again, if I pop it out of gear once again I get throttle back. Now this is a hit and miss thing the whole way down to Albuquerque I can pull it over turn her off and wait a few minutes and then she will run fine then maybe the next time I turn it off it will do it again maybe/maybe not.

Me and my brother have debated for the last two days as to what it is and we think it may be one of several things (But please if you know something else plz chime in):

1) Fuel pump has 180,000 miles on it and has not been changed yet [I]/(we)think the screen may be getting clogged from debri or it just may be going.

2) Brother thinks the Opti is bad but I disagree it is a NEW Delphi from thepartslady and my XP on Opti is when the go they GO.

3) Tranny has 180k also but I cannot see anything that would cause the tranny to stop rpm shut off at 1450rpm.


NOW I talked to Ed over at Fast-Chips and he thinks it might also be #1 but isn't sure because he has never heard of this before and to tell the truth neither have I .....so I hope one of you guys can help thanks in advance.

JT

 

Come on.......Anybody?

 

I changed my fuel pump 3 times chasing fuel delivery problems, mine studdered and chugged ALOT while it was dying, and did weird **** similar to your issue. I checked my computer just like you talked about, my opti was dead so I'm in the middle of changing that now, I ended up changing everything possible in the fuel delivery system, pump, filter, relay, fuse, fuel pressure regulator, and injectors. When I get it running this weekend I'll let you know if it fixed the problem, and if it does it again I'm going to a full Walboro setup. But, to get back to your chugging problem, I chased my gremlins for about three months and it's been my fuel pump/regulator causing all this assache. I hope that helped a little.

 

Okay guys...I'm not sure it really is the fuel pump because I noticed that in my 1st and 2nd gear I can crank it up to 5k with no problems but in 3rd through 6th gear is when it starts cutting out.

 

Can anybody give me some ideas here.

 

bad 02s possibly fouling spark plugs. sounds similar to my LT1. I replaced the 02s/plugs and it was like new