Odd Issue Engine Cutting Out

roary · #1 Thu, March 17th, 2011, 06:08 PM

I recently had my 03 6.0 Evo converted to a Gryphon with custom tunes of 65hp Tow, 80hp DD, 120 Race and 140 Extreme.

I have ran the 120, 140 and currently running the 80 tune. The majority of the time I have had no issues on any of these tunes, but I've experienced an intermittent engine miss on the 120, 140 and 80. On the 120 and 140 they happen in almost the same place so I think it is mostly related to the tune as they are part throttle/under load misses.

The 80 DD is my concern at the moment. I do A LOT of highway miles running cruise. I set my cruise at 4-5mph over the speed limit usually and don't have any problems with other vehicles. But I recently had one that I would pass, then they would speed up and pass me, and then immediately slow down and the cycle would start all over again all while they were weaving in their lane.

So after getting their license plate, thinking they were possibly drunk, I stood on it from 75mph and watched as they accelerated as well. So I stayed in it a little longer than I should have to put distance between us, and as I topped 104mph per my GPS, the engine cut out out like it had hit a fuel cut, then two-three seconds later would kick back in, then immediately back out like a fuel cut. According to the Gryphon my max rpm was 3606.

With all of that said, does Bill normally put in a fuel cut on these or does he normally put a rev-limiter on his tunes? I have my alert on my gryphon set for 3800 rpms to warn me before I get to redline. I also have not created a "custom tune" when programming my truck to take out the normal speed governor found in the stock programming and canned tunes.

But if none of the above is the case, then I believe I may be having an issue with the HPOP not putting out quite enough pressure under high demand situations. I need to find someone around me with AE to datalog pressures and until then I won't know for sure but would like other peoples opinions and thoughts. I have sent an email to Bill but with everything else they have going on, I know he is slammed so I haven't bothered him anymore.

Any idea's?

***Jeremy*** · #2 Fri, March 18th, 2011, 12:29 AM

Try to adjust your options. When you go in there it will show you what your speed limiter is set at. I believe Bill leaves that one stock and allows you to take it higher if you want to. I always set mine to 120ish. I'll bet that was your problem.

BTW, if you ever get yourself into that situation again, just turn the key like your starting the engine and hold it(the starter will not engage) it will override the factory speed limiter, for as long as you hold the key. It comes in handy when I forget to up the speed limiter in the programming.

roary · #3 Fri, March 18th, 2011, 01:32 AM

How on God's green earth did you come to figure out to turn the key to bypass the speed limiter? I'll definitely have to try that just to see if it works...something I would never have thought about LOL

I am going to adjust the options, it just seemed really weird that the factory limiter is set to 94mph, and when I was stock and running canned tunes, it would never get above that. However it let me get all the way to 104 the other night, and the speedo is right on the money verified by my gps.

Had another weird issue tonight, I cranked the truck and let it warm up for a few minutes. After I climbed in, I was putting a destination in my gps when my radio turns off, my gauges swept all the way to the right, then zero'd themselves out and started working again. After 10 seconds it did it all over again. After checking for codes and it doing it a third time I shut down and restarted and it fixed itself.

I would just like to know what the heck happened to cause it and why it worked fine afterwards LOL