Boost drop details, help! Long!

[Cody Forbes]

I'm thinking it's pulling boost and/or timing as the IATs go up and/or as result of knock. 

-Cody Forbes (mobile)

> On May 19, 2017, at 6:07 PM, Eric Huppert <ehuppert at hvc.rr.com> wrote:
> 
> 'm struggling with boost drop after a couple of hard pulls. This ECU in
> previous 20v pulled to 21 lbs. Now in this 20v pulls to 21 first couple of
> hits, then drops to 15lbs . Shut car off, restart, back to 21lbs for a
> couple of hits again?
> 
> Decided to look through my stash of N75's and see exactly what I have before
> pulling current valve out.
> 
> Valve I pulled from my last DD, now parts car turns out to be a h model
> (AAN). And, like the other two valves I have out, all three have 300ish ohms
> vs. the 28-30 they're supposed to have. (one in the now DD, glacier blue is
> 28 ohms and clicks on the output test)
> 
> The "last" pearl white DD seemed to have much better boost down low, and now
> know why! Seems that the wastegate hose was on the long nipple and not
> supplying pressure to wastegate.
> 
> Plan is to pull the N75 and physically test on bench. (passed ohms and
> output test/clicking solenoid)
> 
> Did like the quicker boost with N75 plumbed incorrectly! Thinking I could
> plumb in a MBC once I get this sorted?
> 
> Below is other post from elsewhere detailing everything done to resolve
> 
> So, finally installed my chipped ECU in the glacier blue. Old ECU was
> putting out 11 lbs - 1.7ish which was about right for stock.
> 
> Initial road test with new ECU had 21 lbs on first hit. Then shortly
> thereafter would only go to apx 15 lbs.
> 
> Then discovered that if I shut the vehicle off and restarted I'd get 21 lbs
> again?
> 
> No codes, although I did get a 1111 once (typical for chipped ECU's)
> 
> Car runs smooth and well, will pull to apx 7k with no problems
> 
> History, all work in last month or so, purchased in Feb and worked on till
> recently
> 
> Full tune-up to include narrow tip rotor
> Timing belt etc.
> New borsch correct oxygen sensor
> Gutted cats
> Replaced all vacuum lines
> Replaced FPR with know good as original crapped out
> Cleaned ground points
> Ben swan chip, wastegate spring, 2.5pt (consistent 21 lbs)
> New throttle body hose
> Samco hoses
> Forge bypass valve
> Fuel injectors sent out for cleaning/testing
> Installed new knock sensors (Bosch)
> Pressure checked to 25lbs.
> 
> Checked:
> 
> IAT sensor, ohmed out okay
> TPS, checked out good
> Altitude sensor, checked, seems okay, pulled sensor from car that had
> chipped ECU and put in
> ECU ground to body, good!
> Disconnected MFTS to see if any difference (reducing boost)
> Checked waste gate control, ohms correct and clicks with output test.
> Believe it's good? Was going to swap parts car solenoid in, but that one
> does not ohm out correctly! Now determined glacier white had a "H" N75 which
> was also plumbed incorrectly! 
> 
> Thoughts????
> 
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