LB7: what the hell is a duramaximizer???

[770JOHNNYW]

i just did a set of injectors in an 03 lb7 that was running when it came in now no start...started checking and found a pig tail off the junction block that led back to this thing. pulled the pigtail out and tried but truck was to dead to turn over. do these things **** up or what do they even do?

 

[Dan@PPE]

It is the first product we ever made (pressure box) they work good, mild increase. We still offer them!

 

[770JOHNNYW]

the tech 2 is showing 40000mm3 on the rail psi sensor....what do they do????

 

[Dan@PPE]

reg command is showing 40,000? This is with truck cranking but not starting correct? What is the act rail pressure?

 

[770JOHNNYW]

reg command is showing 40,000? This is with truck cranking but not starting correct? What is the act rail pressure?

no...its commanding like 5000 psi or so cranking but only making around 1000 psi not enough to start i dont guess but the rail psi sensor is reading 40000mm3 and not changing. like i said ran fine when it came in just needed injectors and didnt know if this box went out or i fried it somehow

 

[madmatt]

unplug the two main bail connectors and look for bent pins. i did a set and got a no start after and thats what it was.

 

[770JOHNNYW]

unplug the two main bail connectors and look for bent pins. i did a set and got a no start after and thats what it was.

Man ive checked them over and over and the ficm connectors...
Everything looks good primed up has an airdog also so I know fuels there but the pump wont make any pressure

 

[Atouchofgrass]

Any fuel leaks? Just trying to narrow it down..

 

[770JOHNNYW]

Any fuel leaks? Just trying to narrow it down..

nothing man...just went back outside and tried to start it with charged batteries and still no start.

 

[02greysixer]

What about fuses?


Sint frum tha orijinul smert fone

 

[770JOHNNYW]

What about fuses?


Sint frum tha orijinul smert fone

yep...all the ones under the hood anyway

 

[Evan@InglewoodTrans]

I had this issue and it ended up being a bad injector that wasn't allowing the system to build enough pressure to start. It would only build 500 -800 psi I found it by cutting a spare set of feed lines I bought in half and welding them shut. I then swapped them in until the truck finally started.
On edit: I had 2 that were bad.

 

[770JOHNNYW]

I had this issue and it ended up being a bad injector that wasn't allowing the system to build enough pressure to start. It would only build 500 -800 psi I found it by cutting a spare set of feed lines I bought in half and welding them shut. I then swapped them in until the truck finally started.
On edit: I had 2 that were bad.

You know what man I think your right a friend if mine suggested that but I always only use gm shit ....that's what it is ill let you guys know tomorrow! Thanks

 

[blk smoke lb7]

Johnny disconect the ficm harness and pull the glow plugs and have someone on both sides of the truck and have someone cranck it if you have a hung injector it will mist out of the glow plug the 1 that is stuck.
http://www.youtube.com/watch?v=3LoPLqhxKBM

 

[blk smoke lb7]

In that video it sprays pretty hard but thats the dual fuelers


Also pull the fuses and inspec i bought a set of injectors because when the fuses poped the end curled up and touch the prong on the other side it checked good with a test lite but when pulled you could see it was blown.Also there is a main fuse under the black shroud that goes around the fuse block and you have to remove it to get to it its a 75 amp or 125 amp i do not remember for sure.

 

[Evan@InglewoodTrans]

Johnny disconect the ficm harness and pull the glow plugs and have someone on both sides of the truck and have someone cranck it if you have a hung injector it will mist out of the glow plug the 1 that is stuck.
http://www.youtube.com/watch?v=3LoPLqhxKBM

^ That was the first thing I did when mine had a issue and none of them showed any signs of fuel coming out. After looking for the issue else where for a day I ruled everything else out and then tried the welded off fuel lines.

 

[blk smoke lb7]

^ That was the first thing I did when mine had a issue and none of them showed any signs of fuel coming out. After looking for the issue else where for a day I ruled everything else out and then tried the welded off fuel lines.

I had 2 stuck open and it showed on my truck.ill be damed it wasnt both rear 1s on each side,could have atleast been on 1 side so i didnt have to to take both stinking covers off LOL.Im having a problem with commanded and delivered psi rite now and i would love to install a welded line on the injectors to see if they are returning but i dont think the injectors will like that taking the full pressure with no releif.

 

[blk smoke lb7]

Ya know an even easier idea would be to remove the 2 banjo bolts on the outside of the head the 1 rite behind the altenator and the drivers side next to the glow plug relay and just install regular bolts hence no returned fuel.I think im going to try my own idea saves me from pulling the dam valve covers.

 

[Evan@InglewoodTrans]

I'm talking about sealing of the feed lines it just eliminates the injectors from the equation when finding a leak, basicly just caps off the rails. If you watch fuel rail pressure and it builds after capping them you know your issue is under the valve covers. Then you can pin point which one by swapping the factory feed lines back on until it doesnt build pressure anymore.

On edit: I'm not saying not to pull the glow plugs to check I was just letting him know the problem doesn't always show face that way. What I suggested may not be his issue but atleast he knows it's a possibility.

 

[blk smoke lb7]

I'm talking about sealing of the feed lines it just eliminates the injectors from the equation when finding a leak, basicly just caps off the rails. If you watch fuel rail pressure and it builds after capping them you know your issue is under the valve covers. Then you can pin point which one by swapping the factory feed lines back on until it doesnt build pressure anymore.

On edit: I'm not saying not to pull the glow plugs to check I was just letting him know the problem doesn't always show face that way. What I suggested may not be his issue but atleast he knows it's a possibility.

Ok i see im at the wrong end of the injectors lol