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dmjarosz
06-03-2015, 02:34 PM
I just noticed it this morning. My stealth p/n 11142 makes a different noise than when I first installed it about a month ago. Its hard to explain but it went from a high pitched wine to more of an electric motor sound. The sound is even different when I turn the key to run without starting it. Do these things have a break in period? Computer finally adjusting? Something loose I should investigate further? The car runs just fine, no changes.

BigM460
06-03-2015, 03:45 PM
I just noticed it this morning. My stealth p/n 11142 makes a different noise than when I first installed it about a month ago. Its hard to explain but it went from a high pitched wine to more of an electric motor sound. The sound is even different when I turn the key to run without starting it. Do these things have a break in period? Computer finally adjusting? Something loose I should investigate further? The car runs just fine, no changes.

Only way to really tell would be to look at fuel pressure and fuel pump demand. Don't know if you knew what it was doing to know the difference? Other than that, guess you would have to take it out to check.
I have 2 340's and I can't hear them over the exhaust.

justbob
06-03-2015, 05:21 PM
My new one sounds like its bearings fell out. My two year old one is smooth as could be.


Builder Of Badassery

dmjarosz
06-03-2015, 08:45 PM
My new one just like its bearings fell out. My two year old one is smooth as could be.


Builder Of Badassery

I dont have a way to monitor fuel pressure and pump load right now. One of the last things I need to get for my eaton swap is a tuner.

Bearings fell out?? What the?? Maybe I have a bad pump?

JBeezy
06-03-2015, 09:20 PM
I can hear mine when I turn the key on, barely. Nothing after that. I've put about 7000 miles on it.

justbob
06-03-2015, 10:18 PM
Bearings fell out?? What the?? Maybe I have a bad pump?


I edited.

I plan on replacing the newer one soon as I don't trust it.


Builder Of Badassery

BigM460
06-04-2015, 01:35 AM
I dont have a way to monitor fuel pressure and pump load right now. One of the last things I need to get for my eaton swap is a tuner.


I monitor mine with the Torque app. Just have to get the bluetooth adapter.

dmjarosz
06-04-2015, 04:25 AM
The torque app and Bluetooth adapter seems like the way to go.

So to update, I start the car this morning and the pump is very audible. I opened the trunk and it's the first sound you notice, very easy to hear over the exhaust . Almost sounds like something hissing underwater. Definitely not what it used to be.

Zack
06-04-2015, 07:12 AM
The AEM pumps are far superior IMHO

Blackened300a
06-04-2015, 08:03 AM
Mine sounded a little loud at first, but its almost as quiet as the stock pump now. I have about 1000 miles on it.

dmjarosz
06-04-2015, 01:52 PM
Only way to really tell would be to look at fuel pressure and fuel pump demand. Don't know if you knew what it was doing to know the difference? Other than that, guess you would have to take it out to check.
I have 2 340's and I can't hear them over the exhaust.

I got the torque app and an OBD2 reader today. Fuel rail is 37.6 - 38.3 psi. I dont know how look at fuel pump demand with this app but I see something called load and thats at 26%.

BigM460
06-04-2015, 04:32 PM
I got the torque app and an OBD2 reader today. Fuel rail is 37.6 - 38.3 psi. I dont know how look at fuel pump demand with this app but I see something called load and thats at 26%.

Can't remember how it's listed when scrolling through things, but it shows FPDC (fuel pump duty cycle)on the gauge. Should be in the same area as the fuel pressure.

dmjarosz
06-05-2015, 06:11 AM
Thanks. I found it. That torque app takes some getting use to.

So my fuel pump duty cycle appears to be 48.4% at idle. That seems way too high. Also, the power wire from the distribution box to the inertia switch is very warm, though I haven't upgraded it to 12 ga yet.

BigM460
06-05-2015, 07:44 AM
Thanks. I found it. That torque app takes some getting use to.

So my fuel pump duty cycle appears to be 48.4% at idle. That seems way too high. Also, the power wire from the distribution box to the inertia switch is very warm, though I haven't upgraded it to 12 ga yet.

That is maxed out!! Sounds like you may have a leak or very poor pump output. Going to need to pull it out and look.

justbob
06-05-2015, 07:48 AM
It's been awhile since I data logged, but isn't 49.9% value considered 100%?


Builder Of Badassery

BigM460
06-05-2015, 08:12 AM
It's been awhile since I data logged, but isn't 49.9% value considered 100%?


Builder Of Badassery

Yes! Mine wide open with the hose off, only went to 48.6 if I remember correctly.

dmjarosz
06-05-2015, 08:58 AM
Am I getting a bad reading somehow or is there some major problem? I only ask because I see throttle is at 19% at idle and that cant be right

BigM460
06-05-2015, 09:59 AM
Am I getting a bad reading somehow or is there some major problem? I only ask because I see throttle is at 19% at idle and that cant be right

I don't believe that has anything to do with the fuel pump. PCM probably uses that for timing maybe.
When driven and accelerating what does your fuel pressure do? If pump demand is maxed at idle, your fuel pressure will most likely drop. Should maintain around 39psi.

dmjarosz
06-05-2015, 01:33 PM
Fuel rail pressure drops to around 25 psi under moderate acceleration. I don't want to push it any harder just to see how low it will go. FPDC fluctuates a little bit always but stays around 48.

Looks like im wrenching this weekend!

BigM460
06-05-2015, 02:07 PM
Fuel rail pressure drops to around 25 psi under moderate acceleration. I don't want to push it any harder just to see how low it will go. FPDC fluctuates a little bit always but stays around 48.

Looks like im wrenching this weekend!

Looks that way! Hope it's something obvious and easy to take care of!

dmjarosz
06-05-2015, 02:41 PM
Any chance of it being a bad FPDM or do those just stop working altogether when they fail?

dmjarosz
06-07-2015, 08:49 AM
I pumped most of the fuel out of the tank yesterday by running a jumper wire from the battery and connecting it to the harness coming out of the FPDM. Wow does that pump move fuel! Also, I'm pretty sure its bad because it sounds like its trying to pump sand. Lots of vibrating and grinding noises.

justbob
06-07-2015, 10:04 AM
Next time disconnect the filter and attach a hose to a bucket and have a friend simply hit the key.

I attached a long hose from a fuel pressure gauge to my regulator gauge port and filled two five gallon buckets in seconds with my twin pumps LOL


Builder Of Badassery

dmjarosz
06-07-2015, 10:15 AM
I removed the Schrader valve core and slipped a piece of fuel line over it. Except when I turned the key, no fuel pumped so I jumped it.