Are our ecm's limited in compensation for temp and altitude?

[BuickMike]

So I'm up at 9000 ft in the Sierras and was reminiscing about how the wife and I thought back to when we drove the gn up here back in '99. I remembered how it was slower than a snail at altitude and took forever to build boost. I then turned my thoughts to how I need to pull a little timing or fatten it up a bit whever it gets hot to keep it from pinging. I guess they are super limited in adjusting for iat or barometric pressure from the map sensor? My ecoboost f150 runs awesome up here but it has widebands.

 

[TurboDave]

So I'm up at 9000 ft in the Sierras and was reminiscing about how the wife and I thought back to when we drove the gn up here back in '99. I remembered how it was slower than a snail at altitude and took forever to build boost. I then turned my thoughts to how I need to pull a little timing or fatten it up a bit whever it gets hot to keep it from pinging. I guess they are super limited in adjusting for iat or barometric pressure from the map sensor? My ecoboost f150 runs awesome up here but it has widebands.

Well your ecoboost is a speed density system, while your buick is still running a rather antiquated MAF system which doesn't use the map sensor for anything other than running the boost gauge.

 

[v6turbo87]

The 148 Buick ECM has no MAP sensor input and does not use the IAT sensor for any fuel correction until the outside temp is very low. The MAP sensor in a turbo Buick is only used to drive the LED boost gauge.

 

[BuickMike]

That answered my question guys. A buddy of mine was questioning why I need to adjust WOT fueling and timing to correct for temps. He tunes a lot of obd2 cars and we started questioning whether this car had iat correction tables or not.

 

[TurboBob]

the IAT (in the stock software) is only used to correct the MAF measurement, which does affect fueling but only to correct it back to what it was programmed to be.

There is no spark adjustment for IAT in the stock software.

The altitude is compensated by the MAF which measures the air entering the engine.

As far as making more power at altitude, its really about getting more air into the engine.

Bob