Silverado GM Truck FSCM Delete Fuel Control Module Bypass GMT900

[@jedgillilan1556]

I done the same thing almost 3 years ago and have driven it almost everyday since. I have taken it on a few 4 hour drives and had 0 issues. The only problem is if you totally floor it, it will cut out for a second but I dont run mine hard anyways. I have accumulated around 75k so far and still going just fine.

[@theclamhammer4447]

It’s been done many times. Especially in boosted applications. It WILL work but you need to add in a vacuum referenced mechanical fuel regulator and flash the PCM with EFILive or HPTUNER. First setting is FPCM to “Not Fitted”. As of right now you have no mechanism controlling fuel pressure at all seeing as how the FPCM handles this. You’ll then need to set desired/default pressure at around 400kpa. Last you’d need to change injector offset VS Pressure Delta VS IGNV and injector flow rates to static fuel cell.

[@kennethrohe4076]

Bypassed mine 3 years ago still going strong

[@thedriver02]

That's good to know!

[@kennethrohe4076]

@@thedriver02 i just wired it straight to a switch but it still works 👌

[@thedriver02]

@Kenneth Rohe awesome.... could be an anti theft thing, kill switch.

[@kennethrohe4076]

@@thedriver02 right 😂

[@frankcerda4021]

How does it respond on the open hwy?

[@eurowerx4267]

I bypassed the module to eliminate several parameters as the issue. It will set a check engine light for high voltage because the voltage is adjusted by the ECU.

[@jasondowney8753]

I did about the same thing on my truck. Haven't had any issues

[@thedriver02]

Good to know, how long has it lasted?

[@marcogomez8632]

Hey do you have the diagram to do it please?

[@thenewenglandgrower1313]

First off how long did doing this last you because I have the exact problem and repaired everything that led me to this now if so can u please explain better how I am to do this on my 2011 silverado please

[@thedriver02]

It is still working just fine, about a year so far. You can try jumping the terminals with some wires, just go straight across the connector on the harness and you should hear the pump running. Then it's up to you to either add a switch, or wire up a relay as I did.

[@CaswellCustoms]

What are the relay PIN numbers for each color wire?

[@sciencemansandera]

i'm just curious before this happened to you did you notice a broken ground cable anywhere my friends truck has done this in it is driving her crazy I haven't tried to examine it yet she's got a bunch of hacks working on it thinking they're going to resolve it out of a Chilton manual and it doesn't work like that anymore lol

[@thedriver02]

@sciencemansandera so afterwards I cut the harness apart at the plug and made the repair more permanent, and I found 2 small wires that had corroded together. 2 small one black and one white twisted around each other. So that might have been my problem. It's still working just fine with this method of bypass.

[@sciencemansandera]

@@thedriver02 thanks for the info I went back through my pictures of my Innova scanner and found the final error codes and called the dealership I think we found the problem it may have the same problem as yours but the connection to the fuel pump power module is apparently located underneath where the spare tire is either has a broken wire or is blown and in most cases when you replace it GM hast to reprogram it because like everything they got to get some more dollars out of you lol I'm going back to old cars these newer cars above the early 90s suck I was glad to see your video though because it at least gave me some perspective of things to start working out and now I think I got it it's still gonna cost her probably 500 bucks to fix what at least she will have a truck before winter

[@rodneylawrence3509]

Does this method keep the check engine light on? Thanks in advance.

[@thedriver02]

Yes actually you will in fact have a check engine light after doing this.

[@walk3rshyper314]

How is this running? and does your engine have a fuel return line on it? I got an 08 and I'm told it doesn't have a fuel return line and therefore bypassing the module will result in too much fuel because of the lack of the return line.

[@thedriver02]

It's been running just fine. I've read that it has a "return less" system, but it looks like a lot lines running to the tank, so I'm really not sure if it has a return of some sort or not. But no problems and others have said the same. I'm going to permanently wire it to run this way soon.

[@walk3rshyper314]

@@thedriver02That's good to know. Do you notice any difference at all in how it's running? like acceleration, or driving on the highway or freeway? What's your fuel pressure running at? how much PSI?

[@thedriver02]

@Walk3rsHyper never checked actual fuel pressure, but it has been accelerating just fine getting on the freeway, no stumbling or loss of power noticed. I suspect it might if you were accelerating at full throttle for an extended period like drag strip or something, but foot to the floor for a few seconds or so I haven't noticed anything different.

[@williehollin7577]

Did u use the green/white to or just the grey to pump

[@boostedstinger]

How are you regulating fuel pressure?

[@thedriver02]

No idea, I suppose the ecu is compensating somehow. It's still working just fine.

[@boostedstinger]

@thedriver02 I'd love to hook my scanner to it and watch live data....guarantee it has rich codes and is pulling at least 25%fuel. Probably won't show any issues unless you drive for long periods at a time. Short trips will probably be just fine.

[@boostedstinger]

@thedriver02 keep me updated please!!! I'm curious. I've never seen this work on a daily commuter.

[@dbeto789456]

Did the CELstayed on after the bypass?

[@thedriver02]

Yes it did stay on. Still running just fine.

[@justuploadit92]

Where did you buy your plug and play fscm before?

[@thedriver02]

Amazon, but they are no longer available, at least not a few months ago. It was an actual Dorman replacement part.

[@H2ODiver_Down]

I just bought a vehicle specific plug and play preprogrammed fscm from. Autozone. It was a Dorman brand. $186.00

[@RolandoMota-hh7mj]

Thank you, very good explanation

[@myyume1100]

Theres a easier way to do this. If you have a tuner. You can change a setting from varriable to fixed speed. Yes by doing this will make the fuel b pump to 50% load. I was messing around to figurge a issue im dealing. Your the only that mentions anything close to dealing with.

[@thenewenglandgrower1313]

I no my fuel pump is gone so I may also have issues with pcm or ecm as well atleast if one of those is bad I can bypass and hard wire to see if I can get it to fire 🔥 but if the fuel pump and my ecm is bad I'll need to get it replaced and programmed as well

[@heresthething....4685]

My problem is that injectors are dumping fuel. "Truck will run but it's flooding and smoking like a diesel. Could the FSCM be responsible for that? I could see if one or two injectors went bad I would need to replace some injectors but for this bad of a fuel dump problem, it seems like some kind of programming/message issue.

[@thedriver02]

I'm not sure, my instincts would make me think it's Maf or map sensor, or something on the intake side could be malfunctioning.

[@frankcerda4021]

Was the initial problem the injectors not working? Or the fuel pump?

[@thedriver02]

Fuel pump was not running

[@MrTravisAl]

Usual root issue being intermittent issues in the fuse box/ecm and the like. Because it corrodes. They’re all stacked. And moisture finds its way in and stays sandwiched in between - nice moist, damp and corroded.

[@rowdymclemore4881]

i have no power to my fuel pump fuse or my relay im showing low voltage at my fuel pump pug after running a hot wire to my fuse is the ecu the problem and the fuel module hell if i know lol im jumping over all that bullshit if nothing else as a back up for a later date lol

[@freddyg9026]

ever figure it out? was the truck cranking?

[@brianmeek5236]

This is just one more reason why the older gm are bringing big prices

[@thedriver02]

Hey Guys just FYI it has been running and driving fine for over a week now, no driveabilty problems at all! Do you think this fix will last?

[@JTM_INC]

Has it lasted?

[@thedriver02]

@Tyler Muncy yes so far it's been fine, driving it every week. Not gonna lie it does makes me a little nervous tho.

[@frankcerda4021]

​@@thedriver02what is the harness you install the relay to. Where is ut located?

[@tobysirus4996]

@@thedriver02 GM not happy with you.Want you to leave wallet before trip to poor house.

[@thedriver02]

@JTM_INC yes!

[@Watchout1010]

Variable fuel pressure for different throttle position loads-full pressure for idling,partial throttle...seems as if the milage will fall as will system longevity...

[@boostedstinger]

Its a returnless fuel system and with 12volts constant it will start to show very rich conditions. I actually just diagnosed and repaired a truck where they did the exact same thing. It will start dying and running poor.

[@thedriver02]

Good to know, I would think your right, but so far so good. Mine is basically a beater truck now anyways.

[@Juan_Limitless_Customs]

U can bypass it and add a corvette filter with built regular and mount it on your line and make it have a return

[@boostedstinger]

@juanrodriguez-nb3ic right...but at that point why not just put a fpcm on it?

[@frankcerda4021]

Im currently going thru the same thing. Ive bypassed the fuel pump relay and the pump stays on constantly but it still wont start so i thought my injectors weren't working

[@thedriver02]

Crap that sucks. Have you sprayed some fuel down the carb to see if it pops off? Make sure your wires are redW to black and BlackW to red if your splicing outside the connector.

[@frankcerda4021]

Ive watched your video several times and i wanna try to do that but i dont have the connector under the truck like you show. Where else would it be?

[@thedriver02]

​@Frank Cerda 2007 and newer should have this connector on the module which is usually by the spare tire.

[@devillettuce8406]

Once I did the bypass the truck wouldn't start. Don't bother with starting fluid lol it took to much. Once I put about 3 or 4 ounces of good gas in the throttle body it started and ran long enough to get all the junk out from rolling it over and over trying to start it. Hope this helps. Also if you do the relay bypass make sure you read your relay diagram as in this video his power to relay was green.. mine was yellow but everything "looked the same"..

[@elizondomountaindewherbert3250]

Still working out for you?

[@thedriver02]

@elizondomountaindewherbert3250 yes, still working great! It runs and drives just fine. Some people swear it will run rich, but so far on this one no way! 👍

[@chadwickdemerchant1747]

Why not just replace the fscu

[@thedriver02]

@chadwickdemerchant1747 because it requires expensive diagnosis at the dealer. The plug and play was no longer available at the time, and why replace something every 2 years that's gonna fail again.

[@Marc_Wolfe]

If it's doing 50%, you didn't wire it right.

[@cuivincent9744]

looks like the FSCM module is useless, which can save over 350 bucks.!

[@sonniearchibique852]

Wow I can hear the misfire from here,

[@Fundaykidzz]

Great video … how much is the fuel control module / and install

[@thedriver02]

$600 at the dealer but the problem is in the wiring then maybe $1200 with diagnosing. My truck is a beater work truck farm truck, so I choose this route. Also this could work for someone doing an LS swap using stock ecu.

[@PeterWilcox-f3y]

Awesome