99 454 Running bad

[charger66]

So I have a 99 454 k2500 sub. It has a misfire on 2 and 3. I have done the normal tune up things. Its been doing this for a while but has got worse. Already replaced injectors, FPR, Filter, Pump. Just did intake gaskets they were leaking. And yes it was like this before. Compression is good. 150 to 160 on all cyl. When doing the gaskets found 2 bad lifters. Replaced all. Replaced cap and rotor the rotor was worn. Fuel pressure is 50 KOEF and running its at 55 and if I rev it it may hit 60. Fuel pressure seems low to me that's why I put in a new pump Its an ac delco. I'm at a lose can not figure this out. I'm using hp tuners to do data logs so if anyone has that I can post a file.

 

[8T7K5]

I've been chasing a similar misfire on my 99 454 K2500 Suburban, mine are on 3 and 4. Did all of the things you did except replacing lifters. Pulled 3 and 4 injectors to test and see if they were working right and they were. Compression is good. If I had hair, I'd be pulling it out.

 

[RedBurb]

Charger66---Just today I completed changing the intake gaskets on a 97 454 K2500 Sub (w/180K miles). During my 13th acrobatic test the distributor's mounting flange decided to break (space age plastic). I folded and bought a Accel 100% recycled metal Dis and stabbed it back down the well. Amazingly the shaft and cap realigned to my prescribed marks. Things seemed to be coming together but upon fire-up it threw a P1345 code and is missing at idle. I'm hopeful it's a Cam offset issue. Will know more tomorrow.

Thought I'd mention this since you also replaced intake gaskets. Have you've already crossed-off this potential Cam offset issue?

 

[udidwht]

Possibly a cracked distributor stator ring.

 

[Schurkey]

Possibly a cracked distributor stator ring.

Huh?

Got a photo?

Are you thinking of the magnet in a TBI distributor? They're known to crack, but Vortecs don't have that, or a pickup coil.