If I'm in 2nd or 3rd gear at wot and I shift into the next gear it hesitates. It just feels like I hit a wall. It will not accelerate any more. If I let off and get back on it won't accelerate either. If I shift into the next gear then back into the previous, it will boost and go like a bat out of hell. My no-name mech. boost guage reads 9psi in 2nd/3rd. I have a walrbo, intake,dp,mp stock s5 t2 motor/turbo. I also have a knightsports fbcd, and I have never felt boost cut.

I was also thinking maybe the clip is bad on the wastegate. When it hesitates it dumps all the boost, so thinking either the fcd is malfunctioning or its wastegate related.

If you're damn cig lighter had power we could have figured it out the other day! https://www.nopistons.com/forums/pub...DIR#>/wink.png

in 4th gear A wot @ 2k rpms hes at 5psi: then @ 3k hes at 6psi. Is this normal? In 1st/2nd/3rd car hits 9psi by 4.5K then bleeds to like 4/5 by 6.5/7k....

you are probably hitting fuel cut. 9 psi is boarderline for it.

I have a fcd so that should eliminate the fuel cut. when it hits, if you let off the gas, take it out of gear, put it back in and gun it then it boosts right up to 9-10psi and accelerates solid. I had a truck full of guys behind me on the freeway just as my car hesitated going into 3rd on the on-ramp. I heard a big pop come from the exhaust when it hit, and they pulled up next to me telling me they saw massive flames, Its gotta be runnin rich.

Still could be the FCD. Some FCDs like the racing beat have an adjustment screw to fine tune the unit incase this happens.



Other things that will make something like this is

TPS,

Coolant sensor faulty or not fully in.

Leading coil/ fouled plugs

TID leakage

If this is the red s5 TII from Brads I would look into your tps and why it idles so high.

Gregory

Ok, well i wired the O2 sensor back together, and now it stopped the hickups and runs so so smooth. Idle is still at 1100. Ill be taking the BAC off and using that K2rd plate I have. Then I'll dial in the TPS with a meter and adjust the idle. I think ill be able to bring it down, but if not I'll know theres somethin else. For all I know there could still be a small vaccume leak somewhere. Coolant did sit on the lim gasket for awhile and could have ate some of it up. My dads fd was having similar problems and ended up his lim gasket was bad. I'll follow up on progress later. Oh and the bov IS opening now. I can hear it whistle between shifts :-)

But its still dumping boost in 3rd/4th gear @ wot.... Take that damn fcd off and see if it does the same thing.... Then boost over to my house https://www.nopistons.com/forums/pub...#>/biggrin.png