2JZFC

iTrader: (26)

Does anyone know the PSIG/0-5V calibration for this 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,

svslow

This seems to be pretty spot on with mine.

stevieturbo

With a Mityvac or other similar device, always check the scaling...even more so with Chinese sensors.

lmt0705

iTrader: (7)

I had a bad one, didn't know till the dyno, had to get a gm one.

stevieturbo

If at all possible...I wouldnt be using a Chinese map sensor for any important functions.

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.

2JZFC

iTrader: (26)

Thanks for the replies folks.

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.

oscs

iTrader: (19)

ive dealt with two and no issues. 0-5V is 0-315KPA. let the Holley interpolate and your good to go. Custom 3 bar.

2JZFC

iTrader: (26)

Like I said, maybe I just got a bad one, but not going to risk it. In my table, I have 14.6in vacuum for 0V and 31.2# for 5V. Working my way up the vacuum scale on the Mityvac, the sensor is way off, with 15in vacuum from the Mityvac resulting in 9in vacuum readout from the sensor. That will never work. So, almost perfect on the positive pressure side, totally screwed up on the vacuum side.

lmt0705

iTrader: (7)

I was having the same problem, throw it in the trash and get a good one

oscs

iTrader: (19)

Maybe so, That's the scaling i use. My car idles at 56kpa and never given me trouble. There are tons of people that use them, Good luck.

denmah

iTrader: (2)

stock ecu, micro, ms3, haltech and more i have used with the efi source 3 bar and never had an issue, only holley guys seem to have issues with them.

every other ecu i have ever used you choose standard gm 3bar and its mint

2JZFC

iTrader: (26)

Interesting feedback, Matt. I recently used one on a MS3X with no issues.

I can only go with what I am experiencing.

ssmonte7875

I had one acting like that, i inspected the efi source sensor and i noticed the middle pin was bent up and probably wasn't being inserted into the connector. Straightened it out and the problem was gone. Just something to check

dburt86

iTrader: (2)

ive never had an issue with ms3