310 surge

[ttwndoc]

I have the new TCM and 310 tune. I am getting a surge around 60 mph if I hold it at that speed. This is the same surge that I got on the 275 V2 last year. Anybody else seeing the same thing? Other than that the truck runs awesome.

[08stroker250]

Yes. I see the same thing and have talked to Matt about it. He said it has something to do with the throttle on the tune, and that he wasn't going to worry to much about it since it is a race file. He said you can email or call Spartan and he can try and make some changes if you want them to. He just said it will affect throttle response on that tune. Mine is very violent on my truck, and the 60-65 mpg range is the worst. Mine is made worse by the Air Dog that I have though.

[SpartanDieselTech]

Both of you try to grab me some logs of pedal position, engine rpm, fuel rail pressure, mass fuel desired, and injection timing. I'll take a look and see what I can do. Only had it reported a couple trucks with larger tires- so I have an idea.

[08stroker250]

I run 35's, if that helps any. Im not that concernced about it, but if you want me to log for you to see it better then I will

[SpartanDieselTech]

A quicker question would be is at exactly what engine speed are you seeing it occur?

[08stroker250]

It happens when I accelerate easy or hard to anywhere between 60-70 mph. It only happens when I ease out of the throttle though. If I let out of it immediately it doenst do it really, but it I ease out it will buck my truck like crazy at times. And like we talked about, it takes a good bit to get the truck to quit doing it someitmes.

[SpartanDieselTech]

Originally Posted by 08stroker250

It happens when I accelerate easy or hard to anywhere between 60-70 mph. It only happens when I ease out of the throttle though. If I let out of it immediately it doenst do it really, but it I ease out it will buck my truck like crazy at times. And like we talked about, it takes a good bit to get the truck to quit doing it someitmes.

What engine rpm are you at around these speeds? 1800ish?

[08stroker250]

Yea, its below 2,000 most of the time. But I have experienced light surging above 70 mph around the 75 mph range. It is worst below 2,000 though in that 60-70 mph range. So I would say between 1700-2000 RPM

[ruger311]

i got this surge today hammering down getting on the hwy once i got to speed i let off sort of slow then got back into it a lil bit, surged unless i went WOT

[elibenson]

I had it happen a couple of times today too. It feels like the bucking I get when I am pulling an empty gooseneck trailer on the 275 tune. You kind of feel like you know how it is to have 'shaken baby syndrome'. I think it is because of the touchy throttle. I got it once when I hit a bump. I think my foot jerked a tiny bit, which caused the truck to throttle up, which caused my foot to move again, and so on and so forth. I have found that it take a very steady foot to drive with the higher tunes some times. I pretty much always brace my foot against the transmission hump to keep it from bumping the throttle too much.