LB7: Problems after injector replacement

Jay33089

New member
Feb 2, 2019
9
0
0
North Carolina
I ran and got a stock filter. It cranked an ran smooth as could be. This time it ran good for about two minutes. The lope came back gradually this time and didn’t seem as rough. I’m gonna try to find a fpr tomorrow. It’s doesn’t appear to have ever been changed. Strange how things are fine til you change something. Hopefully this will fix it. My scan tool won’t display balance rates. But I have a buddy whose will.
 

Jay33089

New member
Feb 2, 2019
9
0
0
North Carolina
So I fixed the lopey idle. One of the pins was pushed out of the fuel rail pressure sensor connector. It idles like a dream. I can rev it up and it’s smooth. But when I try to drive it I can go maybe half a mile and it’s like something comes loose. Starts pouring dark gray smoke and knocking. I can shut it off and crank it right back, no smoke and runs fine. I can recreate this at will. If I baby it it goes longer, driving normal not so far.
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,743
5,911
113
Phoenix Az
So I fixed the lopey idle. One of the pins was pushed out of the fuel rail pressure sensor connector. It idles like a dream. I can rev it up and it’s smooth. But when I try to drive it I can go maybe half a mile and it’s like something comes loose. Starts pouring dark gray smoke and knocking. I can shut it off and crank it right back, no smoke and runs fine. I can recreate this at will. If I baby it it goes longer, driving normal not so far.

take it back as is, point out the fails and use that as fuel to get your money back. DONT have them work on it. if they wont refund you, video all the issues to file to the CC company. cover your ass here before you go throwing money at this trying to fix their f**k up.

as for the smoke, hard to say unless you have a way to monitor pulse width, commanded rail/desired rail, timing, map sensor, boost, etc. its most likely the junk injectors they put in there. i wouldnt throw a dime at anything else on that truck till i put known good injectors in.
 

Jay33089

New member
Feb 2, 2019
9
0
0
North Carolina
I can’t take it back to anyone. I did the install. I don’t let people work on my vehicles. I’m new to the diesel world, but I’m learning quickly. I got ahold of a good scan tool today. Balance rates were bang on. They all hovered around +/- 1. So I was officially confused. So I did it old school. I figured an injector was hanging open under load. I disabled them one at a time. I got to #7 and bam no more smoke or knocking. I drove it 3 or 4 miles. I reenabled it and pushed the throttle and the problem started again. Turned it back off and drove home with no issues. Now I know what’s up, just gotta fix it.
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,743
5,911
113
Phoenix Az
You need to see what main injection rate is along with balance rates. Balance rates are half the story.

You will be replacing more than just that one sooner than later.
 

bigmackmiller

Active member
Nov 30, 2008
1,046
2
38
Kokomo, IN
Customer of mine bought some from those asshats and was in the engine about 5 times before he finally returned them and got a quality set, I would do what I could to get my money back and get a good set