need alil help guys

[whthemi12]

Guys I have started to hear a rattle like sound from the front of my express when i accelerate hard right before it shifts in to second. Sounds kinda like a u joint goin out but my truck only has 15000 miles. I also did at trouble code scan with my diablo and p1521 variable resonance induction system solenoid came up. But I change my oil myself and I use royal purple 5w20. I switched to that oil at 3000 miles and never had a code before. So what do u guys think I should do? Id appreciate any advice.

 

[Ike]

Take it back to the dealer, its under warranty.

 

[whthemi12]

Yeah I planned on it. Just figured if there was sumthin I could do at home to fix it that would be nice. I know I need to set the tune back to factory but do I need to put the factory cai and throttle body back on before I go to the dealer?

 

[quietpeen]

nope, all you should have to do it put the tune back to stock

 

[Saltillo Express]

How long has the current "earl" been in it? You switched at 3K miles to RP. But how many miles on the current oil that's in it? Please don't say 12K.

 

[BAILEY1]

Keep us updated on this issue. I'm curious to see what is causing the rattle.

 

[whthemi12]

I had just changed the oil when I did the trouble scan. But ive been hearing the noise for abweek or so. And the oil level and pressure is good.

 

[Saltillo Express]

And you clear it, it comes right back?

 

[whthemi12]

Yes sir. It did a few times but I turned my mds off and it hasnt came back on....yet

 

[Saltillo Express]

Heck maybe the MDS will fall off then you'll be done with it. I have seen in the past where on occasion they will pick up a code, you clear it, it never comes back. But that's an oil viscosity code, like if you dumped 50 weight in it. Which you didn't. And it's rattling. You turn it off with the trinity and the code doesn't come back - what about the rattle - is it still there with MDS off?

 

[whthemi12]

I haven't heard the rattle since but I have been takin it pretty easy on yhe truck last couple days. Only time I heard it was under hard acceleration right before shifts

 

[Saltillo Express]

so you are going to have to put the PCM back to stock to take it in. Post up what they say. So weird. I mean - can the MDS rattle and make noise? I'm going to go out and look at mine.