No start after injector swap

thuglike · May 30, 2020

So after all these years of owning a 6.4 I finally swapped out all 8 injectors. Install went smooth and I checked and triple checked every connection. After I loaded the new tune and cranked it, it cranked and sounded as if it wanted to start but no dice. I figured the fuel system was air bound like on a 7.3. Only code that came up was code 2291 which is low fuel pressure while engine cranking. On my gauge it never went above a 1000 PSI. I'm sure it's an air issue but I don't know. Do I still keep cranking it until it turns over? Or is there a way to bleed the air out?I've never done it before. I get black smoke from my crank vents. Appreciate any help in advance.

DEEZUZ · May 30, 2020

thuglike said:
So after all these years of owning a 6.4 I finally swapped out all 8 injectors. Install went smooth and I checked and triple checked every connection. After I loaded the new tune and cranked it, it cranked and sounded as if it wanted to start but no dice. I figured the fuel system was air bound like on a 7.3. Only code that came up was code 2291 which is low fuel pressure while engine cranking. On my gauge it never went above a 1000 PSI. I'm sure it's an air issue but I don't know. Do I still keep cranking it until it turns over? Or is there a way to bleed the air out?I've never done it before. I get black smoke from my crank vents. Appreciate any help in advance.

Remove the rear banjo bolt on cooler and install a bleeder tool. Cycle key half a dozen times, you should see good clean fuel. You can even crank it with a bleeder in place until it starts....

The bleeder can be an old banjo bolt that drilled on top with a barbed fitting that had a length of hose that goes into a bucket.

thuglike · May 30, 2020

Thank you for the reply I did bleed the system through the banjo bolt on top of the fuel cooler. Ton of air. Im seeing 5000 or so psi of rail pressure on my dashdaq. Getting black smoke during crank. She sounds like its about to fire but just won't. Also my fuel gauge doesn't work..its not going up to level with key on. Also have low fuel idiot lite on. Not sure if related.

DEEZUZ · May 30, 2020

Jesus, wtf did you do.

DEEZUZ · May 30, 2020

Did you disconnect the main engine connector harness at pcm? If so, take it back back off and reseat it.

DEEZUZ · May 30, 2020

Did you replace FRP sensor/UVCH?

thuglike · May 30, 2020

Lol....I know!!!!!

Hood goes up ....**** goes sideways.

Yes I did disconnect the harness....I'll reseat that. FRP and UVCH are 6 months old..I didn't touch those

DEEZUZ · May 30, 2020

Since you played with the tune, retune it

Sixfoh · May 31, 2020

Curious on the injector install. Did you put the metal crush washers on the bottom of them? What was your final torque on the injector hold down? My guess is youre getting fuel if you read 5000 frp and have black smoke. But not compressing enough for ignition. Keep us informed

thuglike · Jul 3, 2020

Update......

Bit the bullet and bought brand new 60 overs from RCD.

Swapped the injrctors and bled the high pressure side with a home made banjo bolt bleeder. Cycled the key and dumped the fuel into a milk carton. Did that about 8 times. She fired right up and is running better than ever. It's crucial to bleed the air out. Anyone that has never swapped injectors before..make sure to bleed the system.

thuglike · Jul 3, 2020

My guess is the first set of injectors I bought were bad. I wasn't gonna open the valve covers again with any uncertainty...so I bought new. I should of done that to begin with but the 100 overs I got were cheap...and I paid..twice!!!...Don't do cheap...lesson learned

lincolnlocker · Jul 3, 2020

Dam thuggy! Live and learn.. but glad you got her running good!

live life full throttle

Connor M · Jul 4, 2020

Out of curiosity did you replace all the o rings with new on the first set and lube them up? I swapped an injector and was getting a ton of air through the return o ring because I was lazy and just threw it in without swapping the o rings. Took me way longer than I want to admit to diagnose the issue. No amount of bleeding could solve it because that o ring kept introducing tons of new air into the system, and more than it could handle.

thuglike · Jul 4, 2020

I did not change o-rings..
They looked good...and I was told they only 500 or so miles on them.....I guess I got lazy too...lol

Sixfoh · Jul 4, 2020

O rings and the crush washer at the bottom/tip are both equally important to do new every time an injector is taken out. Glad you got it all settled though. Are running dual hpfps for those 60% overs?

Also thought I'd mention I did the same custom banjo bolt bleeder tool on mt build! So crucial to get the air out. I think I cycled through 10 gallons of diesel into cans before realizing the tools hose was in fact long enough to reach the filler neck.