I know there seem to be a ton of threads about MDS but I haven't read much about my specific issue/noise I seem to be having.

I know many turn it off because of the exhaust sound, don't think it does much, doesn't like how it feel, etc.

But I have never really noticed or had mine do enough to bother me but for some reason when im going up smaller hills where just a light throttle can be held to get the truck over, a weird sound resonance sound comes through and is really noticeable without the radio on and such.

It literally never does that sound any other time, and will only do it on the same certain smaller hills. If I click to tow/haul od off button it instantly goes away, if I get the transmission to shift down it will go away, or if I obviously push the gas pedal down a good amount to get the truck to accelerate it goes away which is why im def assuming its the mds. I have only read one thread from 4 years ago that described the same thing I was having.

Anybody else had this?


Also I have a P1521 code stored in the truck but due to the fact that I just bought the truck alittle while back I dont know how far it goes back. Everyone seems to always say its because of the wrong weight oil, but all the code books state it as P1521 Variable Intake Solenoid #1 Circuit Malfunction. Is that the same thing?

Thanks

 

If you recently changed from standard oil to synthetic it is possible it will throw that code i believe, or possibly if the sending unit is bad, i believe it is on the passenger side of the block right above & back a little from the filter...

Just my thoughts on the oil code

Cant help much on the other as i dont have the fancy MDS on my truck

 

If your talking about the noise that is best described as if your running water outside or your toilets refilling, in short 2-3 sec spurts, I have that too. Lol.
It's your EGR valve kicking on. Kinda annoying but normal.

 

hm idk mines kind of a weird buzzing rattle sound, not like flowing water.

It specifically only does it at around 35 mph on a slight hill with very light throttle. Never will do it any other time, and if I click the tow/hail button or the gas any harder it instantly goes away.

I thought maybe it was detonation from some bad gas or something and I still had half a tank of that last 89 I got this week. So I filled the rest up with 93 which atleast would get me up to 91 if it was good gas, or if it was bad it would put me where I need to be. But it was no change.

Like I said its specifically on certain hills at that speed and throttle control. Like I can almost guess and tell you when its about to do it. It was enough that my friend in the seat was like wtf is that sound.

But I have 0 codes, and truck runs fine other than that noise. If I didn't take those certain roads to get to his house (we carpool to work) or if I wasn't babying it on those certain hills id never hear it.

 

Also on a side note it seems as if my stored code has now went away?
Is it normal for it to just stay blank and then say done?

Also this is the one where you do your trip button and turn the key on to show things like bulbs are out and stuff. But according to the link on the website these numbers dont match up to anything. Can anyone tell me what they mean? Its just a S 125, . 283, and a C 447.


Video that shows stored code isn't there now.
http://s1046.photobucket.com/albums/...t=IMG_0533.mp4



Video that shows using your trip button with key.
http://s1046.photobucket.com/albums/...t=IMG_0532.mp4

 

Water rushing through a pipe is what I meant...
If it sounds like a hissing ratcheting type of sound lasting 2-4 sec. at low speeds I still say its your egr valve doing its thing...cycling unburnt exhaust gases back into the throttle body.

This thread satisfied my curiosity mainly because it doesn't affect performance...

https://dodgeforum.com/forum/3rd-gen...mpartment.html

 

I wish I could get someone to hear it but unless your in the truck there is no way. To me it just can't be a normal operation especially beens its not like I have an aftermarket intake or anything like most that complain about the noise. Im hoping its just the mds making weird noises.

Got any info for my videos I posted?

 

Thats different than any c-code readout I've seen.. The readout usually ends with "00-00" signifying it's done displaying codes. When you did this, your gauges all self tested right? From what I've read that seems to be a printout of your software version. Alot of guys have the same exact codes, or a very close variant. Kind of makes sense.

 

And they are all 06+ trucks... Canbus crap... So thats most likely true. Its def not your mds via that check anyhow, thats for cluster and electrical. The p code would be more relevant.

 

C447 - ???
S125.283 - software v 125.283?

Some guys have hr1815 too... I'm betting that's hardware revision 1815