hesitate at higher speeds??

[ryanb]

Just built some tunes for my LB7, I flashed just a single tune (dynoed 65HP). Heres my issue; it runs great up to 70-72 MPH and then its like its starving for fuel. It will hesitate and then take off again get to like 76 and then do the same thing again. I can't figure out what it could be. I data logged it and it shows "MAP kPa" seems to be the first thing that really drops while staying in the throttle. Could it possibly be a limiter I missed? I went to just a 20HP tune that I screwed with and it did the same thing. The truck has a airdog II 165, K&N intake and 4in exhaust. Thanks for any help.

[WisconsinHick1]

Check your limiter tables again. Do it happen at or up to a certain RPM spot?

[ryanb]

When I data logged it the highest RPM it hit was 2239, speed is about 72ish then like 76/77 and then it would stop. One guy thought it could be something to do with a boost limiter?

[WisconsinHick1]

Yes it could be a boost limiter also. Would you mind posting the tune up I could look at it this weekend.

[dieselguy9311]

i would doubt that it is a boost table. as long as you leave that stuff stock you can run build a pretty big tune without ever running out of fuel. i would think more than likely you have a bad spot in your fuel or timing table. or asking for too much timing/fuel. lb7 can not control there boost very well at all so more than likely you will get a over boost code or an under boost code. if your not getting one of those than i doubt it would be boost problem. yes i would help if you had the tune posted up. then we could help alot more. dont worry about it not being perfect we all started somewhere.