Fuel system control module
January 1st, 2016, 9:25 PM
#12
if you unplug the fpcm does the fuse stop blowing? If not, the wiring may be shorting to grd intermittently.
the fpcm fuse only feeds the fpcm. the fuse blowing can only be from a bad fpcm, wiring shorted to grd from the fuse box to the fpcm or the fuse box shorted internally.
I would disconnect the battery, the fpcm and do a short to grd check from the fuse pin that feeds the fpcm.
the fpcm fuse only feeds the fpcm. the fuse blowing can only be from a bad fpcm, wiring shorted to grd from the fuse box to the fpcm or the fuse box shorted internally.
I would disconnect the battery, the fpcm and do a short to grd check from the fuse pin that feeds the fpcm.
January 18th, 2016, 9:41 AM
#15
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Sorry for the late reply, I replied from my phone but forgot to hit submit apparently.
The wires run along the side of my frame from the front, back to my box, and then transitions to the top of my frame at the box. The wires don't have the plastic cover in that transition area. The wires were rubbing on the bottom of my cab, and over time chaffed through one of the wires.
The wires run along the side of my frame from the front, back to my box, and then transitions to the top of my frame at the box. The wires don't have the plastic cover in that transition area. The wires were rubbing on the bottom of my cab, and over time chaffed through one of the wires.
January 18th, 2016, 6:03 PM
#16
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On my way to work this morning I noticed my truck was driving rough and sounded louder than usual.
When I accelerate, it starts making a bad vibration noise coming from the front end and doesn't have as much power as it should. When I let off on the gas pedal the vibration stops. Between the bad vibration and lack of power I can't go any faster than 120 km/hr.
When I took my truck to the dealer about my previous problem with the FSCM fuse blowing, they replaced my FSCM and reprogrammed it. Which didn't fix my problem, because my problem was a chaffed wire going to my FSCM (which I didn't find until after installing a new FSCM). I fixed the wire 300-500km's ago, and haven't had a problem until this morning.
Do you think my problem is related to them reprogramming after installing my new FSCM, or do I just have bad luck and something else is messing up on me?
When I accelerate, it starts making a bad vibration noise coming from the front end and doesn't have as much power as it should. When I let off on the gas pedal the vibration stops. Between the bad vibration and lack of power I can't go any faster than 120 km/hr.
When I took my truck to the dealer about my previous problem with the FSCM fuse blowing, they replaced my FSCM and reprogrammed it. Which didn't fix my problem, because my problem was a chaffed wire going to my FSCM (which I didn't find until after installing a new FSCM). I fixed the wire 300-500km's ago, and haven't had a problem until this morning.
Do you think my problem is related to them reprogramming after installing my new FSCM, or do I just have bad luck and something else is messing up on me?
January 18th, 2016, 7:47 PM
#17
imo it is something else. I mean you can never say never in this trade but the programming is pretty idiot proof and it would have been there immediately if it was wrong.
hard for me to say what it could be from the description alone.
I can tell your reluctant to return to the dealer after the first trip. I kinda amazed they charged you for fix that did not work; unless they weren't asked to diagnose it.
hard for me to say what it could be from the description alone.
I can tell your reluctant to return to the dealer after the first trip. I kinda amazed they charged you for fix that did not work; unless they weren't asked to diagnose it.
January 18th, 2016, 9:30 PM
#18
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They diagnosed it, but couldn't tell me the exact problem. They told me it could have been either my FSCM, or my fuse box is corroded. They offered to replace both parts for a pretty penny but unable to guarantee a fix. So i'm reluctant to return to the dealer, yes.
It seems as though the truck is shuddering due to lack of fuel when I accelerate? Also, when I started it this evening I noticed it turned over a few times before firing up. That makes me believe it's not getting enough fuel as well.
It seems as though the truck is shuddering due to lack of fuel when I accelerate? Also, when I started it this evening I noticed it turned over a few times before firing up. That makes me believe it's not getting enough fuel as well.
January 18th, 2016, 9:54 PM
#19
yep, don't go back to that dealer.
do you have a scan tool?
if the system is going lean at all times or during a high fuel demand acceleration event....it will show on the fuel trim data
is the exhaust manifold cracked or are there broken manifold bolts?
do you have a scan tool?
if the system is going lean at all times or during a high fuel demand acceleration event....it will show on the fuel trim data
is the exhaust manifold cracked or are there broken manifold bolts?
Last edited by tech2; January 18th, 2016 at 9:59 PM.
January 23rd, 2016, 12:51 PM
#20
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I have a 2008 GMC Sierra 1500 with a 4.8 v8 4 wheel drive I went out to start my truck one morning and it didn't start fuel pump was not kicking on just replaced it less than eight months ago I have no power to my fuel system I checked the fuel pump fuse with a test light and there's no power fuse is not blown. Every other fuse in the truck is good. Why am I not getting power to my fuel system? What could be the issue.?