Help With EFISource GM-Style 3-bar MAP Sensor
http://www.efisource.com/shop/gm-sty...sor-w-pigtail/
Is anyone using this MAP sensor with a Holley EFI? If so, what Sensor Type did you select? If you selected Custom 3bar, do you mind sharing the Calibration Curve you defined for it? Did you ever verify the curve is accurate?
Thanks,
If it's just for logging some other pressure and no actual controls...no problem. But trusting your engine to a cheap *** $30 sensor when a proper one is maybe double the price ? Just makes no sense to me.
Hell even those at the $100-200 range...still cheap insurance.
The problem I am having started intermittently and has worsened. Takes about 6 cranks to start and will not idle well under 950. Above that, it idles well but occasionally will suddenly die. Immediately dies when the tranny (TH400/PTC combo) is put in gear. Cracking the throttle to help it recover does absolutely nothing. If I screw the idle up to 1250 or higher, it will go into gear and drop to 850, come back up to 950 but not die. I replaced the IAC and tried different settings with no change.
When I bought this MAP sensor, I built a custom 3bar calibration curve. While debugging this problem, I noticed my boost/vacuum gauge was reading 12+in vacuum, but the Holley gauge panel was displaying around -8 (I am using the PSIG option) and 49kPa and using the cells in that range of the tuning tables. Looked at the MAP sensor setup page and it was defaulting to Holley 3bar with an offset of 2.25PSIG. I know I didn't select that because I am not even sure what the Offset means
The response from svslow triggered my memory and after some digging, I found the spreadsheet I used originally to build the custom 3bar calibration curve. I set that calibration as my default in the Holley and used the onboard air system in the car connected directly to the MAP sensor to do regulated comparisons at 5, 10, 15 and 20psi in KO/EO mode. Did not expect it to be dead nuts accurate because the regulator gauge does not have the granularity, but the Holley and regulator gauge were within a few points each time. Feeling confident, I put everything back and fired up the engine and the Holley is still reading -8 at idle. Seems to be totally ignoring the custom calibration when the engine is running. I then put the Mityvac on it to compare vacuum and the vacuum side is so far off, it's ridiculous.This MAP sensor is crap! Maybe I just got a bad one but won't chance getting another.
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every other ecu i have ever used you choose standard gm 3bar and its mint







