MAP Sensor Issues

[Boyes50]

Hi Guys,

Brand new to HP and have been doing a ton of reading and learning. I recently purchased an MPVI3, with the intentions of doing some baseline tuning before having a reputable local dyno tuning service dial the truck in. I've been working through the tune and getting a baseline tune file together to get the truck idling. Some basic information on the truck:

- 2006 Sierra 1500 P59
- LQ9 24x Short Block
- L92 Heads/Intake
- 227/237 Cam Motion Cam
- LS3 Throttle Body w/ X-Link
- 50# Flexfuel Injectors

I was able to work my way through the forum and find tons of information to help me get the truck baseline tune working to at least start the truck. It was idling horribly and extremely rich, and when I opened scanner I see the LS3 Map Sensor which I'm using an adapter harness to from the OEM LS1/Truck style MAP Sensor is reading 95kpa and not moving regardless of running/idle/throttle open. Thinking I must have an issue with the tune file, I rigged the OEM Truck Sensor up and connected it to the factory connector, adjusted the MAP Settings back to the truck settings, and started the truck. The original truck MAP Sensor and harness read correctly, and the truck runs well with it connected. My assumption then is that I have an issue with either the sensor or the adapter harness, but was wondering if anyone had any diagnostic information for testing the MAP Sensor before I order a new harness and/or sensor. The sensor is a 12594942, replacing the original 09359409.

Thanks!

[blindsquirrel]

There really aren't any exceptions to the 'if you need help post your tune file and log file' instructions, unless it's a question about general theory or about what a certain table does.

[Lakegoat]

The MAP Characteristics for Linear and Offset should be 128.20 and -0.30 for that MAP sensor. Did you try those numbers?

[edcmat-l1]

Go to alldatadiy dot com and buy a subscription for your vehicle. Cost is 19.99 for a month. Then you'll need at least the connector diagram for the other map sensor, or buy a subscription for that vehicle.

As a side note, you might want to contact your local tuner before you make too many changes. I don't "finish" tunes. Most other qualified tuners are the same way. Chances are your local guy is going want your stock file, or you put it back to stock. If a customer can't get me their original unmodified tune file I charge for MDI2 "return to stock" flash.