Flutter noise at 15psi

[going4speed]

Car has a stage 3 fwdp computer. Trying to get to run on computer controlled boost. Boosts past 15 on the stock gauge and there is a flutter feeling or sound coming from the engine. Seems the computer cant control the boost for some reason.

If I bypass the solenoid and connect a grainger instead I can put the boost exactly where I want it

What to look for to get to computer controlled boost?

I know they are supposed to learn but seems learning over 15 psi sounds like a real bad idea...the car does not hit boost cut off but dont know if it should with a stage 3.

[tryingbe]

Stage 3 FWD computer uses a 2 bar map sensor, which means the ECU is BLIND to any boost above 14.7psi. What are you trying to do by going over?

[going4speed]

I'm trying to just drive the car with computer controlled boost. I took out the grainger valve and reset the computer and the car cannot control boost at 15psi. I'm trying to figure out why. I prefer the driveability of computer controlled boost. I am quite happy if the car just stays at 15 psi. This car was meant to be my daily driver but I dont trust the thing at all

[zin]

Sounds like you'll need to set the boost to just less than 15PSI, or go to a 3-bar map/cal...

Mike

[GLHNSLHT2]

get the # off the ECU and contact cindy to find out how to hook up the vac lines.Maybe they need to be 88 T1 style or maybe 88 T2 style.

[zin]

Good point!

Mike

- - - Updated - - -

Good point!

Mike

[going4speed]

is it possible the wastegate solenoid is flaking out like trying to control boost but cant?

Opened the smec...some chip in there with handwriting I could not read except for the mileage of 81k..hmm mysterious. Need to get a stock chip.

[going4speed]

This flutter noise turned out to be a bad coil. The plastic/phenolic end had micro cracks in it. It was allowing spark to escape and jump to the coil terminals.