Overboosting in cold.... where to start?

[highlander]

OK.

Car: 05 LGT 5 MT

AP: v1.5

MAP: eTune from known vendor

Mods:

UP/DP/MP/CBE

AEM CAI

Perrin TMIC

Prodrive EBCS

ACT clutch/LWFW

LW crank pulley

GFB BOV

 

Logged car after new eTune - found no boost.

Reloaded original eTune - found boost, but map not set for CAI, TMIC, or EBCS

Loaded yet another eTune map and car boosted fine (warm weather).

 

Twice now the car has thrown P0244 in 35 degree ambient or less, third gear WOT, 3-4kRPM. Overboosted to about 22psi if my memory serves (hard to look diplay where it is mounted when you are distracted by the CEL engagement).

 

Options:

1. Retune after logging in cold air?

Gonna be hard to complete as the CEL will kick in during logging runs. Hints on how to do this appreciated.

2. Remove EBCS, reinstall OEM BCS and retune?

 

I'm sure the EBCS was the original sticking point with the eTune as the vendor had tuned for the other mods frequently. I went with the EBCS as it offered more control options, especially if I uprgaded to a different turbo with an EWG.

 

AFAIK, there are no local shops doing AP tuning in central Va. which is why the eTunes (plus the cost savings over dyno time).

 

I understand the mechanics of the car, but I am a tuning virgin when it comes to the ECU controlled options.

 

Not trying to set the world record, just have reliable all weather performance when I want it.

[rao]

If the tune didn't account for the EBCS you are lucky that the only problem you are having is some overboost in the cold.

 

The Wastegate duty control solenoid tables need to be adjusted - not hard to do but very necessary.

[highlander]

The car was eTuned for basic Stg 2 mods.

I added the TMIC, EBCS, and CAI and purchased a new eTune for those mods.

 

The new map didn't boost. I reloaded the first eTune just to verify no leaks and the car boosted.

Sent logs of both back to vendor and received another new eTune map.

Car boosted normally then (in warm temps).

 

Now getting overboost in cold air.

 

I don't recall this occuring last winter (retuned in October 07), so I am wondering if I have a mechanical issue keeping the WG from functioning properly.

[mickeyd2005]

The car was eTuned for basic Stg 2 mods.

I added the TMIC, EBCS, and CAI and purchased a new eTune for those mods.

 

The new map didn't boost. I reloaded the first eTune just to verify no leaks and the car boosted.

Sent logs of both back to vendor and received another new eTune map.

Car boosted normally then (in warm temps).

 

Now getting overboost in cold air.

 

I don't recall this occuring last winter (retuned in October 07), so I am wondering if I have a mechanical issue keeping the WG from functioning properly.

 

Were you running the Prodrive and new etune map last year?

 

From your description, it sounds like you weren't.

 

There is a WGDC IAT compensation table that needs to be adjusted.

[highlander]

Had a Stg2+ eTune from 2006-4/07.

Installed TMIC, EBCS, and CAI with new map from vendor to support mods.

Identified boost issue in Fall of 07 which was something in the map. (original 2+ map boosted, new map didn't with new parts on both)

Logged for vendor and received new map.

 

Didn't notice any issues last winter.

 

Now twice it has overboosted in cold.

 

Question: Would a kinked or obstructed vacuum line in the boost control circuit cause this symptom? How about an open vacuum line somewhere?

Just thinking it through; trying to rule out mechanical/physical issues before tuning ones.

[highlander]

Am I in the neighborhood with the kinked hose?

[holyjoetart]

It has to do with the cold air.

[mickeyd2005]

The things you mentioned would cause warm weather overboost problems as well.

[highlander]

OK. I realize the cold air is the culprit if nothing has changed. I'm just trying to rule out other potential causes as I do not recall having these issues last winter with the same tune/parts.

Just thinking out loud....

 

Thanks for everyone's advice.

 

I have contacted a tuner familiar with my current map and he assures me that he can tune out the cold air issue if that is the cause.

[qikslvr]

The overboost issue is more than likely due to the WGDC atmospheric/AIT compensation tables in the base map. Most of the e-tunes don't get adjusted for the cold weather. I'll post up a screen shot of the table(s) in question shortly.