Pretzel

Hello, I’ have 3 tunes. GMS1, Trifecta and ZZPs Hp tune and all started fresh with high boost of 20psi for GMS1 and 26psi for Trifecta and ZZP. But over time (4-6 months) they degraded down to 15psi boost? When this happed with the Trifecta tune I called them and they said they have seen this happen before this the Auto trans models and sent me a special tune. But it didn’t work. Not sure if the adaptive learning was in place I pulled the fuses for the ECM and TCM and that didn’t work either?
Any idea why this is happening?
thank you.

Oldblue

First I’ve read about this, perhaps contact ZZP and get their input, for their tune. I don’t think Trifecta still supports the HHR SS tune. The boost loss could be a pressure problem, leaking connections in the charge pipe, intercooler check the clamps.

firemangeorge

Are you losing boost with the GMS1 ? Had mine for 10+ years and never lost any. It's always been around 19-20 max.
If it's affecting all 3 tunes, I would think it's something besides the tunes themselves. What,,,I don't know.
How many miles on this SS ? Maybe you've got a turbo getting worn.

Pretzel

I did contact ZZP and they think something mechanically is wrong?

Pretzel

I didnt have the GMS1 on too long. The SS is still fresh, less that 45,000 miles.

Pretzel

I have not gone backwards on the tunes. Will load Trifecta and see what happens.

2005HHRauto

It's always a mechanical issue 100% of the time.

Don't blame the program, the 'tune'
Think of a 'tune' as just a change of 'torque' allowed at any & every operating point of your engine, whatever the 'tuner' wants, he can do, he can change.

Losing boost means 1 of 2 conditions of your engine.

Condition 1 = you just increased the efficiency of your engine.
Example: You replaced your exhaust catback with a 3" system, which means your boost pressure will be less, as you won't need as much 'boost' to reach the 'tunes' 'torque' allowed programmed conditions.

Condition 2 = A mechanical issue.
Examples: Worn parts, engine, turbo, sensors, or a leak somewhere in the pressurized turbo system caused by worn parts, failure of parts, or a loosing of parts, (leaks).

If your program, whether it's stock or changed, allows you to see 'X' amount of boost, & it's decreasing over time, you have a mechanical issue as the program hasn't changed.

"Learn Down" is really a misunderstood concept.
It is just your program trying it's best to give you whatever 'torque' values that it has been programmed to give you, at any & all programmed conditions.
If something changed, good or bad, the program will 'learn' quickly, to give you the 'torque' values that are called for in your 'tune'.
Example: You just installed a better turbo on your engine without changing your program. Your added power boosting turbo will overwhelm your program, & your program
will do its best to 'Learn Down' to the allowed programmed 'torque' setting in your program.

A neat 'trick' at the dragstrip is to reset your ECM just before every run. Try it, you'll like it. LOL

"Learn Up" = when you put a 'tune' in your ECM, as a 'tune' is always causing a increase the 'torque' values allowed, somewhere in your program. LOL

A good 'tune' is always the best thing you can do to your 'buggey' whether it's totally stock or modified.

donbrew

Sounds to me like it is adapting to a gentle driver.

RJ_RS_SS_350

Sounds like a leak. Bypass valve, vacuum tank, etc

2005HHRauto

Na, the ECM 'learns', as it needs to meet all the 'torque' values requested in the program.
Our ECM is a 100% 'torque' based unit.

Now the automatics TCM 'adapts' to the slow wearing of the clutches & bands over time.

I call B.S. on needing a 'special' tune for automatics.

The ECM & the TCM have separate jobs to preform, & don't 'talk' to each other. LOL