(1998 F-Body) 2 Bar histogram issues

Hey guys,

I've searched on the forum for this, but haven't been able to find anything...

I have a 1998 Camarobird PCM with a 2 BAR OS on it. My gauges and chart properly recognize the 2 BAR MAP and list the correct values. However, the Primary VE vs. RPM vs. MAP that I use in my AFR error histogram does not properly show the MAP rating (it outputs as though it were a 1 BAR MAP).

I do apologize if I've missed something obvious; can anyone point me in the right direction?

FWIW, I do see the changes that need to be made on the 99+ PCMs after the 2/3 BAR OS upgardes, but according to the documentation, no changes are necessary on the 98 units (in regard to the Manifold Absolute Pressure (SAE) PID).

Thanks,

Blake

Well, in typical fashion, after getting frustrated and posting up a question, I found my own answer.

For anyone who may search for this in the future...

To make this work, I used the "VE - AFR Error (98 2bar)" histogram that comes with the software (2.22 version here currently). This still didn't work, as-is, however. I had to delete the "Manifold Absolute Pressure" sensor, and switch to the "Manifold Absolute Pressure (SAE)" PID instead. I then switched units from psi to kPa, and kept the labels as per the stock .hist file.

FWIW, I used this modified .hist as a base for my VE - Narrowband, VE - Wideband, VE - Lamba Err (custom PID), VE - Fuel INJ Duty, etc. Essentially anything VE needs based off of one of the 2bar '98 VE histograms, though they apparently don't work correctly box stock (hence my confusion).

Hope this helps someone in the future. My tuning should go much better now that my histograms actually match the rest of my data properly. ;)

Thanks,

Blake

The help file http://www.hptuners.com/help/vcm_edi...ters_gm_os.htm is always a good place to start

Quote:

---

NOTE: On 98 V8 vehicles there is no 2bar MAP PID. The SAE MAP PID has been reprogrammed to register the correct amount of boost. Also, due to the fact that the 98 Vehicles do not report an OS ID, the histograms will not automatically enlarge for boosted regions. You will need to create your own or load histograms from the saved folder. Pre-configured histograms for 98 2bar vehicles are located there.

---

Quote:

---

Originally Posted by Bill@HPTuners

The help file http://www.hptuners.com/help/vcm_edi...ters_gm_os.htm is always a good place to start

---

The preconfigured 2bar histograms for 98 vehicles didn't work. :)

If you read my second post, I had to change from the MAP sensor to the MAP PID before they functioned correctly.

Your documentation states that you can use the SAE PID for the MAP, which is right, but then your 98 2bar histograms use the MAP sensor instead of PID, which does not seem to refect the 2bar MAP correctly.

I can upload one of my edited .hist files you can compare against your preconfigured .hist files if you like. I don't see any reason my car would be special vs. any other '98. If it isn't "different" in any way, you might want to tweak the included histograms to use the PID instead of the sensor, to prevent future confusion.

Nope, should work fine as stated, otherwise you likely have a custom pid made that is screwing things up ;)

Quote:

---

Originally Posted by Bill@HPTuners

...otherwise you likely have a custom pid made that is screwing things up ;)

---

Probably it. I have several custom PIDs. I didn't do anything to any of the MAP stuff though, just Wideband related calculations.

Ah well, it works now. Dancing banana time. :yay: