Running rough

Joel godard · October 26, 2021

Had dreaded lifter tick. Replaced all lifters. New head gaskets, intake gaskets , coils, wires, plugs. Adjusted rockers to 22 ft. Lbs. By the manual. Torqued heads by the book. Using torque angle gauge. Got it together. Runs rough. Any ideas?

Sharpz · October 26, 2021

are you throwing any codes? Have you drove it at all? A few suggestions is check your plugs for fouling. Doing the front easy to get to ones will be good enough to check. Also make sure all of your injectors are seated straight and plugged in.

CamGTP · October 27, 2021

Check for vacuum leaks as well.

sspeedguy · October 27, 2021

Does it idle ok then run rough under throttle? Cuz that what mine has started doing after a very similar rebuild, except mine was driving for around 1000 miles before it started this and also i fitted a new stg 1 cam at the rebuild.

Joel godard · November 1, 2021

Have pulled valve covers since.It runs good for a second at start up then starts running bad. With valve covers off. #1, 4, and 6 rockers aren't moving. They move when I'm turning over by hand. It's a new vlom.?????

Joel godard · November 1, 2021

#7 is working

Joel godard · November 1, 2021

It ran good before. Just had the lifter noise. It was only one lifter on #1 cylinder that failed. I've done mechanic work for 25 years until my health failed. But haven't worked on this particular problem. Have worked mostly on 60's-90's cars and trucks.

Joel godard · November 1, 2021

Oh yeah. Getting po300 code only.

CamGTP · November 1, 2021

If it's only the AFM cylinders then it's likely the lifters again. If the rockers don't move at all then the lifters are stuck.

Joel godard · December 19, 2021

Update! Fixed that problem! The lifters on 1,4,and 6 were sticking in the guide trays. Runs good now. I bought new felpro head gaskets. And bought the metal felpro intake gaskets. Runs good but after driving around for a hour or so I got a p219a code. I did smoke test on the intake. No leaks. I pulled fuel rail and checked fuel injectors. They are working great. Bought new o-rings and installed the injectors back in. Still getting p219a code. Help!

Supreme Pizza · December 19, 2021

I wonder if your 02 sensors on that bank are bad. I did a similar repair on a 5.3, because the intake lifter on #7 was collapsed. The engine was creating excessive vacuum in #7 cylinder, on the intake stroke. This was causing the engine to draw oil into that cylinder, and then push it into the exhaust system. I'm wondering if you had one or more cylinders doing the same thing. The oil may contaminate the O2 sensors, and then the computer would not be able to fine tune the fuel ratios properly. On your lifters that were sticking, was the problem caused by improperly aligned lifter guides?