Engine clatter increases with higher settings on Quad box

[srichard]

I noticed this weekend something that worries me:

with the Quad box OFF, at around 2200 rpm in 6th, under partial throttle acceleration, there is a slight engine clatter that can be heard, soon hidden by the turbo whine.



When I turn the quad box to the 60 hp, the clatter is louder, and at 100hp it is quite loud. It seems that under full throttle acceleration it is not nearly as noticeable (turbo noise covers it?) but just cruising in the lower gears, especially with the box on the 100hp, if you try to lightly accelerate with partial throttle, the engine is NOISY. at lower RPMs, it is not an issue, but beyond the vicinity of 2200 I can really hear it.



is that a normal diesel noise? or should I call quadzilla to enquire about that? They clearly say in their user guide that the engine is not supposed to sound any different with their box.



thanks.

 

[JCleary]

According to Quad, it's the timing change. It will sound different. Mine does.



You may want to re-read the instructions. I read and understood that a change in pitch is normal. Perhaps we interpreted the statements differently.



If your fuel rail pressure sensor is unplugged, your truck would be super loud and it wouldn't run right. I don't think it's what's happening with yours.