Anyone here install a capacitor inline on the FICM of an LB7 to filter power and hopefully help injectors live longer? There was a thread about it some time back on DP but the fella that was gonna draw up a schemtic never got around to it. Anyone that knows what micro farad value, and perhaps knows which pins are what on the FICM chime in would ya?
LB7: Clean power cap to save injectors
- Thread starter Mike_S
- Start date
I think that no matter what mythical device you put on your truck your injectors will eventualy fail :hug:. The capacitor was rumored to possibly help them from cracking bodies but I think that failure is the least common of all your still gonna have high return rates, leaky seats, smoking or wut ever. Mite as well just wait for them to shit then try the new version with a hardend ball and seat.
not tryin to change topic....
is chevy installing thhe new version injectors you mentioned when doin the warrenty work. just curious just got mine done in september.
I cant say for sure but supposedly if they where remaned in late 08 and newer they had a hardened seat so if your dealer has older ones on his shelf guess what 
. This is only info I gained from reading these sites and have no facts.
. This is only info I gained from reading these sites and have no facts.haha ok thanks my odds are good it took them a couple days to get the injectors thank you though
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They came from the factory with hardened ball and seat...or they wouldn't have lived 15 minutes. I agree that this will not stop all failures, but it should stop the failure that the warranty is designed to cover...which is failure due to the injector recieving poor/false signal due to a dirty power source. Why do you think that all of the newer models dropped to lower control voltages (LLY=48 volts, LBZ/LMM=24 volts....LB7=96 volts, all voltages AC. Thats hard to control with an overall 12 volt DC system.) Also keep in mind, the local trucks here that I have seen with the most injector troubles are the guys that cheap out and only change one battery at a time, or never clean the connections....sounds like a bit of evidence that the theory could ring true. Seems like good insurance to me for the hour and 25 bucks it would cost.
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If thats the case what was changed on the injectors in the end of 08 or lets say Bosch's injector revision? If it was such a simple fix such as adding a cap inline wouldn't GM do this as part of a update when changing injectors? It seams like there is just alot of rumors floating around and is hard to get good facts I wish somebody would post some facts maybe some pics of the old injectors vs new torn apart. Pics of worn out seats or cracked bodies so we could get some of the myths and rumors out of the way.
i have never heard of the dirty power ruining injectors. i am certain gm is full of challenged folks designing and redesigning the parts in our trucks, but a am positive that if it were a power/ground type failure they would have addressed it a long time ago as a "campaign/tsb" to stop these issues from costing them a fortune.
There was a major electrical system re-design in '03 I believe...Ben would be able to say for sure better than me...let me see if I can find that thread on DP...there is some good reading there and a few really good facts supporting this theory. I'll post a link later.
Theres alot of reading to do here...but there is alot of good info there.
http://www.dieselplace.com/forum/showthread.php?t=279174
http://www.dieselplace.com/forum/showthread.php?t=279174
Last post by oddplanes was what, May 26 2009. I sure wish he had uploaded that schematic on the cap. Would have been nice to at least look at it.
There is nothing dirty about the signal to the injectors and adding a cap, depending on the actual resulting bandwidth can actually hurt you.
So given my knowledge of electronics, since I practice it for a living, the 'cleaniness' of the signal to the injectors is not the problem...at all.
However I am interested in knowing whether or not, with time the wires being frayed etc if the timing is off a bit. I would think you as a driver would note a change in power/mpg first.
So given my knowledge of electronics, since I practice it for a living, the 'cleaniness' of the signal to the injectors is not the problem...at all.
However I am interested in knowing whether or not, with time the wires being frayed etc if the timing is off a bit. I would think you as a driver would note a change in power/mpg first.
I have to agree. The injectors are dying due to internal cavitation at the upper rail pressures. The later LB7 designs hardened some of the areas that were affected.
If you want your injectors to live forever, make sure your fuel is well filtered and cap the rail pressure to about 10,000 psi max.
Perhaps that is what the magic device was doing?
well if the mileage some guys are still getting i dint thinks its to big an issue. i had a friend call me the other day asking about a tuner to get him more mileage. so i asked what he was getting now, he said 22 on highway trips and 20 around town. this is an 02 ext 8ft bed. thats nothing to be ashamed of
Interesting that with all of his secondary filtration systems and whatnot a friend of mine has replaced his injectors twice. Still runnin on one good battery and one bad one...and nasty dirty battery connections. Also curious why GM re-vamped the electrical system on '03-'04 LB7's.
Perhaps not, but the fact that GM spent all that money streamlining the electrical system sugests that maybe they were onto the same thing.
really? what changed? Cause the LLY FICM still works on the earlier electrical system. Injectors rails and heads are different, but the controller swaps over IIRC.