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Map sensor issue


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After doing some logging today. I noticed that my TPS was only 81.1 at wot. I then also noticed the ecu was reading in the 50's on the map (mgp). I recently updated to latest firmware. So I thought it was that had messed some settings up. Anyways I calibrated the TPS and it went well. I then tried the map sensor. It gives me an error <5 kpa 5> from bap. If I change the map sensor to subaru v7-8 the bap value is correct. If I then choose v1-6 again then it doesnt give the correct reading, any ideas? The motor idles correctly even tho its not calibrated tho. I have a v6 Subaru.

v1-6 65kpa

v7-8 84kpa

v9 101kpa

bap 83.8

v44 plugin ecu running 4.4.9

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Hi Cake,

some version 6 WRX's need to have the map sensor selected as Subaru V7-8, press F4 to save to the ECU and press F2 and save to the PCL file.

Carry out a MAP SENSOR CALIBRATION and PRESS F4 to save to the ECU.

The MAP should read around 100 - 101 Kpa at sea level.

Try this and report back please.



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Hi Dave,

I have tried this. The Bap reads 83.8 and the v7 subaru reads 84 as per first post, the problem is then it doesn't idle properly it jumps the afr's to the 10's and if I put it back to v1-6 it idles and drives fine. Im not at the coast im 1500-2100m above sea level.

After paying around a bit more I noticed its idling in different blocks on the fuel table as well as it seems more stable and use alot less fuel. ie to get it to idle -60 to -50 blocks at 1000 rpm use 30.5 where as it now uses 24 in block -50 to -40 with the v7-8 map calibrated. I guess that means ill have to retune everything.

Any idea why the v1-6 doesnt work tho?

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looking at your PCL runtime values it would appear that the BAP value of 83 is possibly correct for your altitude, but I can't say for sure.

Setting the MAP sensor up so that the BAP and MAP read as close as possible will be a start.

Has this engine been already fully tuned.

Under your Fuel setup, Main, you have OPEN LOOP AFR TABLE TURNED OFF.

I notice you also have CLL Control activated, has this been tuned correctly.

Was your engine tuned at this altitude or at sea level.

Your IAT FUEL trim table has some strange values negative fuel trims around the 20 degrees c etc.

Your warm up enrichment tables have some values that I would consider a little high around 60 -70 deg etc.

Basically I see tune parameter settings that will definitely contribute to your rich mixture.

An overly rich mixture, can create wet or heavily carbon fouled sparkplugs.

All of these conditions will lead to poor idle quality and low manifold vacuum, which will cause the fuel table cell number to be a bigger number than it should be if the MGP was correct.



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The car was tuned at this altitude. I have been turning some of the features on like IAT, fuel over run & closed loop as none of them where setup originally. My fuel usage has always been very high, so I have recently started learning about tuning as a result been discovering these issues as I go along. As its almost winter now ill be editing those AIT as I go along. It doesn't get that cold here -10 is prolly worst case scenario. The settings are from a subaru v1-6 base map tho.

I wait for the ECT's to get to 80 before I do anything so the enrichment and corrections don't mess with anything. But like I said its literately idling in a different fuel blocks with the v7-8 map setup.

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Looking at your original post, where you said your BAP is reading 83.8 kPa, and that MAP (when set to a V7-V8 calibration) read 84 kPa I would say that the V7-V8 calibration is definitely correct for your setup.

When the vehicle was originally tuned, was the MAP calibration set to V5-V6 or V7-V8? If it was set to V5-V6 then I think it would be best to retune your fuel map. If you have a Wideband O2 sensor connected it would be best to monitor your AFR/lambda and use Mixture Map or Quicktune to correct the fueling as required.


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