[sawtooth1]

OK so i had the dpf delete only and loved the sound from my truck. Now i just went to a dpf / cat delete and have a huge hair dryer sound. When i first crank my truck it sounds great then i guess the egr cycles either on or off while ideling and the soft hairdryer sound goes to a loud very loud hairdryer instantly. This happens about 30 seconds after the truck is frist cranked. Its so loud is drowns out the great tone sound of the engine. Is this normal? If so i may put the cat back in place but it just blows my mind that you cant hear the great tone anymore. I also think i have a small exhaust leak where the straight pipe connects to the short piece just before my factory muffler. The reason I think i have a leak is that when i'm driving and start off and give 50-70% throttle i hear the hairdryer sound from inside the cab. Its very noticable and sounds aweful. Is this normal?

 

[sawtooth1]

I've heard so many say by removing the dpf and cat and leaving everything else factory that the sound is great. However, what i hear is the sound of rushing air in the cab and a big hairdryer outside with no engine tone at idle. Just curious if this sounds correct or not. If this doesnt sound right then i need to figure out the problem.

 

[sawtooth1]

Ok now i'm going to blow everyones mind. So today i go to the muffler place and they inspect for leaks underneith the truck. They lift the truck with me in it and tell me to run the engine at 2000 rpms. All sounds good to me inside and they don't find anything and no signs of black around any connects to signal a leak. So i'm leaving thinking thats just how the sound is suppose to be. As i'm pulling out the truck sounds so quiet and i give her 50% throttle go 1/2 mile and everything sounds great inside. Then i stop at the light to trun right and give the same throttle again but this time the roar inside the cab starts again. What the hell is going on? What ever it is its coming from the passager side rear of the truck and sounds just like a exhaust leak. This is driving me crazy and is very noticeable in the cab. Do you guys with all stock except for dpf/cat delete expereince this same thing? I don't understand why the truck sounds good for a couple minutes then the very noticable roar of air sound starts in the cab. I'm stuck now and not sure what to do....

thanks,

 

[sawtooth1]

Is this the problem?

Well i discovered something today that maybe the problem but its seems strange this could actually be the culprit. Anyway, i discovered how to monitor the EGR valve (at least i think i did) so i took it for a spin last Thursday. Low and behold the noise was gone (magically) and the EGR seemed to be working fine. Today i get in the truck and crank it up only to notice the EGR is no longer opening. Percentage open shows 0%. So i'm wondering if the noise would return and it did. I drove it 15 miles and the EGR never opened and the noise never left. So is it possible the EGR is the culprit? Also, what are the side effects of a closed EGR valve other than the noise i'm hearing through the exhaust?

 

[sawtooth1]

What tunee are you running? The EGR does not cycle while driving running the 210, 250, 275, or 310 tunes. It doesn't cycle at with the 275 or 310 tunes. You would also be getting the code P0401 if your EGR is stuck closed. I also highly doubt this is the cluprit of the noise....

I'm currently running the 40hp dpf delete but have also tried the stock dpf delete and 75hp. I was using the signal for Command EGR on the Spartan DashDaq and noticed when the EGR was working the sound was not there but when the EGR signal showed 0% the sound returned. Very strange.

 

[sawtooth1]

You need to scan for codes when its doing this. If your getting the P0401 code, your EGR is sticking closed.

Ok thanks I'll check it out. I thought a warning light or something would come on the dash of the truck if a code was thrown.

 

[sawtooth1]

I checked for codes and nothing came up. It did say Mil was off or turned off? Is that something i need to turn on?