HarleyHauler

Howdy folks!

After replacing all injectors, CP3, and adding a new 'add-on' fuel filter (between stock and CP3), now I crank the engine and it won't start.

I bumped the ignition about 8 times and made sure I could feel fuel flowing through the lines in and out of the new 'add-on' fuel filter. Because the truck had been sitting for about 6 months, I am charging the battery, but I would have thought it would have cranked over.

Any ideas on what I should check next? Is there a fuel line bleeding procedure I am missing?

Thanks in advance....

railroaderone

I hate to say if you have one injector not firing or stuck open it can cause this also if you are not building 3k in fuel rail pressure it will not start. Hope this helps

Spooler

Did you adjust the valves when you replaced the injectors? If not, you will need to do that since the exhaust rockers have to come off to replace the injectors.

madhat

No fuel line bleeding procedure, the CR system is self bleeding.

You are saying that you have good fuel pressure on the low side?

I would pull all of the connectors on the injector harnesses, the MAP sensor and RP sensor and clean them with alcohol and a small brush, let them dry and reconnect.

Like mentioned above, if you don't have enough RP, the truck won't start. Smell your oil, does it smell like diesel?

Did you follow all of the torque specs when re-installing the injector tubes and lines? too much/incorrect torque will cause a leak between the injectors and delivery tubes. Was the valve lash correctly set?

HarleyHauler

I adjusted all the valves after replacing the injectors, and all injectors are brand new.
Hard to get a torque wrench on the injector tube collars, but did not over tighten.
As far as I know I have sufficient low end fuel pressure. Won't register anything on the gauge until it turns over (running a GDP mechanical LP).
Should I pop the valve cover back off and clean all injector wires with brake cleaner, along with all the injector harness connectors and MAP / RP sensor connectors? I did not clean the injector wires prior to reattaching.

madhat

I wouldn't use brake cleaner. Use regular isporal alcohol. It's enough of a solvent to clean, but it evaporates well and does not leave residue.

The torque on the connector nut is 37 ft lbs, the lines are 22 ft lbs. They are easy to over tighten. I had to use a crow's foot with a torque wrench, there is a formula for that, but I think I ended up using 20.8 ft lbs (it was only one inch of extension). Taking the injector plugs off/ loose helped me get in there with a torque wrench.

Clean the connections on the outside of the valve cover. The wires to the injectors should not be a problem unless you have trash in your oil.

HarleyHauler

Will do -- any reason to use dielectric grease once they are cleaned?

I will need to get a crow's foot for each of those then. I will loosen them all and re-torque as you suggest.

No trash in the oil -- I was REALLY careful about being clean throughout the process, and the oil was pretty fresh (less than 3K miles) before starting.

madhat

I would not use dielectric grease. It is a mild conductor, but when you're using weather proof connectors it's not needed. Also, I believe it does more harm than good with voltages less than 12v... I think the injectors are 5v. If you want to be thorough, lightly put it around the seals.

pw58

is your fca plugged in? I forgot to plug mine back in, just about blew my gasket when it didn't start rite away

HarleyHauler

Yes, checked all connections.

HarleyHauler

Found out last night that the fuel 'bowl' wasn't filling. Think that I need to prime the fuel system -- will try that and see what happens. With the mechanical LP (there is an inline check valve) it may not be pulling fuel through the system.

HarleyHauler

Update (for anyone who cares to know):

I found out that the fuel pressure gauge I had was defunct by installing a second mechanical gauge at the CP3 (the original one was at the stock fuel filter housing). Found out that the stock Lift Pump was putting out 8 psi but nothing registered on the original gauge.

So now with the new gauge in place, went about starting the engine again only to have it knocking like crazy (still). Did a manual injector test (using one of the CR block-off tools) and found that when I blocked off cylinder #6 it actually ran smoother!

When I went to remove the injector at #6, I found that one of the bolts used to hold down the injector was only finger tight. I removed and inspected the injector and found some fouling (remember less than 5 MINUTES of run time on these brand new injectors) so cleaned and reinstalled. Restarted, same issue.

So I did the following:
- Removed and inspected ALL injectors
- Moved the injector that was at cylinder #6 to cylinder #4
- Reinstalled all injectors, torquing everything precisely
- Rechecked the valve clearances

Started the engine, still knocked like crazy. Blocked off injector at cylinder #4 and ran smoother! So, it appears that one of my BRAND NEW injectors is faulty!

Now off to get a replacement and get this problem behind me...

ssteve58

It's good that you found your problem. I had the same thing happen to me, with new injectors, but I was lucky and it was number 1.

Dr.Dizzle

What vendor did you get the injectors from?

ssteve58

I got my injectors from Injectors Direct, but I think i caused the problem with mine. I don't remember letting the torque off of the injector before I installed the tube, so it didn't center itself. I sent it back to them and they tested it and had it back to me in the same week. no charge. They are very nice to deal with. My truck is running great now.