BLKSTAGE3

My car went in to get the 500hp vmp kit and now there is no boost in 1st or 2nd but there is boost in 3 and 4. I know this isn't very informative but I'll update later when I find out more.

Any ideas or thoughts?

They originally said it was the tune causing it to happen. That doesn't make sense to me though.

onederful100

the gear shouldn't make a difference.
and i dont think Justin at VMP would tune it that way.
i'm sure others with the same kit will chime in. but he is a great tuner.
please post more info and dyno sheet when available.

BLKSTAGE3

It definitely seems to be an electrical thing which would be related to the tune.

The speedometer only goes up to 30 no matter what, and is slow getting up to that for the given acceleration of the car and in 1st and 2nd the car makes no power and the second the boost should kick in the car immediately goes back into vacuum and kicks down the power. 3rd and 4th gear are both running and producing boost though.

onederful100

vacuum leak?
was your boost gauge hooked up before and was making boost properly?
Justin can fix the tune if it is the tune. call him or email, see what he says.
are you able to datalog, or dyno run file?
but i would check to see if everything is connected properly, no leaks anywhere.
no CEL codes? limp mode?

BLKSTAGE3

They were checking for vacuum leaks and yes the boost gauge was hooked up properly before.

Limp mode wouldn't make sense for only 1st and 2nd, that would be all gears. We're thinking the SCT device given with the tune may have been defective and wasn't actually transferring the tune properly.

onederful100

does it make full boost and power in 3rd and 4th?

BLKSTAGE3

yes, it's perfectly fine in 3rd and 4th

wcgman

I had an SCT that was starting to fail applying tunes and it (tuner itself) would throw an error when the tune application failed. Not saying that you dont have a defective tuner, but when I had problems with it, it was pretty obvious there was a problem.

grabber blue gt

With your VMP 500 were you given the 2.49" or 2.55"? When I got mine for my 2010 I got the 2.55" as the 2.49's werent out yet and a few people were worried about belt slip when they were first hitting the market. Maybe you are getting belt slip? A good upgrade would be the P51 tensioner arm which will clean up the slack in the belt. Justin at VMP is a great tuner and its definitely not a problem with the tune. Try datalogging it and sending it to him just to verify its nothing tuning wise.