Diablosport Forums

I loaded the 65RWHP (std tune) into my 2005 Chevy. I got great performance and fuel economy right away. After driving it for about 500 miles or so I got on it and suddenly the engine wouldn't rev past 2000 RPM in any gear. I pulled off the road, shut the engine off, checked my air intake (which was fine). After I started it up again, it was fine. This has happened twice since then. Any ideas?

Are you running any other aftermarket tuning devices in the truck?

I am using the K&N cold air intake kit but no tuner other than the pedator.

RobertJacob, Have you changed your fuel filter lately? What code did you get a 1093? If so and you have changed your fuel filter go to one of the larger duramax forums and search of 1093.

Lccmo has a good point, i change my filter every other oil change. It could also be a P0101 air flow issue which i have seen with some aftermarket air intakes but that only seems to happen on Cali. emissions equipped trucks.

Ok, after reading the replies and my original message, I thought I should give more data. This problem acts as if the rev limit has been changed to 2000 rpm. The engine revs and cuts and revs and cuts if I try to push past 2k rpm. I have driven another 500 miles on the 85 hp tune and it is just fine.

RobertJacob

have you checked the codes? Does it do it stock? Have you changed your fuel filter? The 2000 rpm limit sounds like a 1093 code, the usual causes of a 1093 are
1) clogged fuel filter
2) the rail relief valve spring is weak.
3) running a BIG tune - (65-85 isn't big )

Usual fixes for a 1093:
1) change the fuel filter
2) add a lift pump
3) shim the relief valve.

Goto www.dieselplace.com and do a search for 1093.

[quote="lccmo"]RobertJacob

have you checked the codes? Does it do it stock? Have you changed your fuel filter? The 2000 rpm limit sounds like a 1093 code, the usual causes of a 1093 are
1) clogged fuel filter
2) the rail relief valve spring is weak.
3) running a BIG tune - (65-85 isnFuel rail pressure relief valve and EGR plate. Just got mine replaced under warranty

I just had this happen as well. I have been running the Diablo tuner set at "65" with an S&B air intake for about a month now. I changed the fuel filter at the same time and it has been running great ever since.

However today when I got on the freeway, it revved to 2000rpm and then surged and would not go back above 2000rpm. I checked the code, and yes it is a P1093 which I looked up the info on from thedieselpage.com forum which says this can also be attributed to sudden changes in atmospheric temperatures. I am in NorCal and yesterday we had a high of 88 degrees, today it's only going to be 58 degrees.

For now I have reinstalled the factory tune, and reset the code. Is this something that I should be concerned about though in the future? Is it a fluke, or possibly related to the use of the tuner?

I have this problem a number of times. Does it happen when you floor it and then back off suddenly? If so, your truck has a minor momentary loss in fuel pressure and when it catches back up the influx in different pressure trips the code. It is a pain in the ass but that tiny glitch will throw the code. Also after you floor it lay off the throttle easily and that should help.