PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

UnPlug Map Sensor, Idles ok, Plug in MAP sensor, no good - HELP

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Old Nov 22, 2012 | 08:38 PM
  #1  
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Default UnPlug Map Sensor, Idles ok, Plug in MAP sensor, no good - HELP

Well I finally got my 5.3 front mount single turbo xtreme blazer done enough to start it up. Here's my combo and the problem.

2005 5.3
2000 PCM and Harness
Custom Turbo Cam
LS1 Intake
60lb Siemen Deka
On3 76mm turbo
Log Manifolds
3" DP
AEM Wideband
HPTuners with Speed Density 2 Bar Enhancement

Problem I am having is, for some reason that I cannot figure out, when I leave the 2 bar Cobalt map sensor plugged in, Runs SOOOOOOO rich it will barely start up and run. Floods out.

If I unplug the MAP sensor, it will idle on its own, rev smooth etc etc.

What the heck am I doing wrong?? MUCH thanks will be appreciated to help me figure this out. Thanks!

First File is my Tune.

Second file is saved Scan with Map Sensor plugged in (Having to throttle it to try keep it runningm billows smoke from exhaust with strong odor)

Third save file is MAP unplugged (No smoke, idles somewhat good, surges a little)
Attached Files
File Type: hpt
SDStarterEnhancement3.hpt (468.9 KB, 198 views)
File Type: hpl
RunningSuperRich.hpl (6.2 KB, 172 views)
File Type: hpl
UnplugMap3.hpl (19.7 KB, 228 views)
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Old Nov 22, 2012 | 08:51 PM
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This happened to me years ago. I left it unplugged for like 4 years. Ran great, power was great. Mileage was great.

Then I had another issue that caused my drivers side cylinders to not fire.......we tracked it down to a PCM issue. I got a new PCM and BAM....the MAF came back alive too.

So in my case, something 4 years before caused the PCM to not recognize the MAF any more.

.
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Old Nov 23, 2012 | 06:39 PM
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Factory GM Map sensor corrected the problem!

Apparently cobalt SS has both a Map sensor and Baro sensor. The cobalt map sensor is a 1 bar with IAT built in, NO GOOD FOR 2-BAR SETUP! Have to either use the BARO sensor or GM Map Sensor #12580698.

That's some good info so you guys don't foul plugs and dump gas on the oil for no reason.
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