Ever find the issue here? My truck will idle but when I go to drive it. It has an intermittent problem like this where it runs rough and sounds like it cut one bank of cylinders and won't hardly accelerate
LB7: Ficm problems???
- Thread starter MAXX IT OUT
- Start date
Yes I did, I had the stud on top of the injector snap off. Every time it has been a hard parts problem and under the valve covers.
Not cool my truck will start and idle maybe just. Little hiccup every now and then but when I try to drive it it cuts a whole bank it seems like tore into it tonight we'll see what I find tomorrowbjust did injectors Maybe 4 months ago hopefully I don't need a ficm
On the last go round it would idle fine for ever and rev to about 3500 before it would cut out and run like crap then die or after a short time of driving it would kill the truck. I hope yours fix will be as simple as mine.
I hope so I've had nothing but troubles since moving to TX and needtogether this thong going and then a spare car
well turns out that since I was in a hurry to get my truck going I didn't tighten the injector wires down all the way so I got that taken care of now the truck wont start its giving me the issue that I had before the fuel gauge will read empty and the truck just cranks
no it had about 3/4 of a take the truck did this for a while right after I changed the injectors where It would randomly read empty if it sat there for a min sometimes it would go back to the actual fuel level. then it just started working fine now its wont start at all just cranks
So I swapped in a different ecm and the fuel gauge goes to the correct level and will still crank but no start? I'm lost and when I try to hook up Definitely live it will say pcm not connected
Went out this morning with having the batteries disconnected all night. And pulled the ecm fuse. And put it back in and it started right up ill see if it gives me any more problems
Now the fuel gauge reads that its empty again and just cranks any ideas? It started and ran this morning
This is with the original ecm I don't know what to do I'm about to take it somewhere but don't know any shops in Houston may have to bringit to the dealer but that will get expensive
Hate to raise this thread from the dead but I'm having a similar issue. Anyone find the root cause? I recently did head gaskets and added ARP studs to my 2001 Duramax. Got everything back together and she fired right up. Shut it down because had a coolant leak on the front of the engine (broke an o-ring). Fixed it and fired it back up and ran WAY better than it had with a bad head gasket. Warmed her up, flushed water, added coolant, and changed oil/filter. Still ran great. I also had bought a FASS 150, So went to install that last. After install of FASS 150 I found that the fuel gauge would read empty and the oil gauge would jump from 40-~120psi when cranking. Found these issues to be associated with a ground I forgot to reconnect. After reconnecting ground to cab they worked great but truck will no longer start. Will crank and has great fuel pressure, it is like the injectors aren't firing... Any thoughts?
Stumbled upon this thread also and am interested. Did headgaskets and ARP studs on my 05 lly a while back, truck ran great for quite a while. Out of the blue it started running on what seemed like half the cylinders and fuel gauge went to empty. Injectors were bench tested when i had it apart and all checked out good. Now it cranks but will not even try to fire. Buddy had a Snap On scan tool on it and showed no codes at all, and everything looked good on that. It's got about 137,00 miles on it, did the 2 and 7 injector harness fix on it already. Can crack injector lines and theres fuel to them when cranking. Like previously posted, seems like the injectors aren't firing. I'm open for thoughts or ideas also. Thanks
it's quite common for the pins in the large bale connectors on the driver side top of engine to have the pins get pushed back or bend when putting them together. pull them apart and push each pin to make sure it's seated all the way out and none are bent.
check FICM fuse and power at the connector if the fuse is good. verify all related grounds are good and have low resistance
check for no security light on dash
verify clean cam and crank sensor signal
make sure fuel pressure is at 1500 psi or more while cranking
make sure both batteries are good with voltage above 10 volts while cranking
check if white smoke / unburnt fuel from exhaust during cranking, if yes check compression
Not sure it helps but when I was having intermittent errors on the class 2 data bus, I would find my fuel gauge would go to empty. I think I've narrowed the data bus issue down to an aftermarket radio module (chime and steering wheel control replacement), but not 100% sure until I drive for a few more months. Truck would remain running, just the fuel gauge sitting at E and the security light would also turn on.
Maybe there is a possible comms issue on the class 2 data bus, but it seems like the scanner should have been showing some Uxxx codes.
Maybe there is a possible comms issue on the class 2 data bus, but it seems like the scanner should have been showing some Uxxx codes.