Boost Spike Problem

[big nasty]

I run 18psi and @ 5000rpm in 3rd gear it spikes to 25psi before I can let out of it. The truck shifts @ 5900rpm, I have no problems in 1st and 2nd gear. I have checked the exhaust there is nothing blocking it I dont have cats and the mufflers look in ok. the first time it happened it burned a plug. Anyone have some input?:shrug:

 

[Slider]

Check all vacuum hoses?

 

[Screaming01L]

where are you pulling the boost reference from? Make sure its not on the same line that the bypass is on. I had very similar issues and it turned out the diaphram in the bypass would leak after 15 or so PSI and having the gauge on that same line squed the readings. Although, mine did it in all gears.

 

[big nasty]

I have looked over the lines and it was not doing this 2 weeks ago then I drive it and boom. There was a vacuum line kinked but I fixed it