Morning folks,

My 6.4 has 243k km on her now and up here in Canada this time of year one day the AC is on and next day the heat is on.

I noticed at idle when my heat or AC is on (doesn't matter which) every 20-30 seconds I get a slight hiccup and my rpm's drop ever so slightly then goes back to a normal rpm range. This will repeat when I have the AC or heat on at idle only.

I did my front belt and belt tensioner about 15k km ago.

Thanks in advance.

 

Mine does this too ever since the EGR delete.

 

interesting, I have my EGR's.

 

My truck does this as well. I'm deleted with the Gearboxz electron. Egr is still intact just blocked off. I've honestly never thought much of it. Now I'm kind of wondering what it could be.

 

This is most likely cause by your a/c compressor cycling......If you have selected defrost, floor/defrost of have it in the auto position....even in heat mode the a/c clutch still cycles.

 

Ok so here's a little update on my hiccup noise. I've been running the GearboxZ electron tuner for the last 10-15k miles. I ran the original DPF-R before that with no issues. All my weird noises started when I got the electron tuner. I just got my mini maxx today and after my install I drove a while and let it idle a while to see if the noises stuck around. No more weird hiccups or loping. I don't know if that will help your situation but it helped mine.

 

2nd this. its probably the a/c compressor cycling on and off.