How to Check your GM LT1 V8 MAP sensor

[@3121cKOne]

Your (MAP) sensor is faulty.... Most ALL Manifold Absolute Pressure Switches should read about 1.2 -1.7 Volts at startup & idle then read at a maximum 5.0 Volts when the sensor unit is at it's highest manifold pressure or in other words at (WOT), wide open throttle. Your (MAP) sensor is giving a lower reading under more pressure. Voltage always increases under more load... ie. vacuum.

[@1989hondakid]

So I bought a 93 Pontiac firebird trans am 5.7l lt1... has a aftermarket cold intake ,what i find strange is that i dont see a maf sensor on it like other firebird lt1?? I change map sensors and iat sensor .. and was wondering why my car doesn't have a maf sensor , there is a small module wired up and hanging there ,any suggestions

[@rodneyobrien4624]

93 doesn’t have a maf....maf is 94-97

[@chrisatty865]

I have the same lil cube in my 93 firebird formula,did you ever find out what it is?

[@lindyp38]

Where can I get the seal for the sensor ? It’s the small orange colorEd rubber seal

[@davissunglasses]

Still need one?

[@lindyp38]

@@davissunglasses went to the local Harley dealer. Thanks

[@gbouc1536]

Video was good, but wish you would have given results at 5, 10, 15, 20, and 25 inches of vacuum for reference info. Thanks again

[@GearheadGarden]

+G Bouc +G Bouc You're right and I was thinking about that while I was doing the video. Unfortunately, I was having trouble getting a good seal on my vacuum pump so the readings weren't as steady as I would have liked. The big thing is that the voltage drops should be around a volt for every 5 PSI of vacuum all the way down to Zero at around 25PSI. Should never need more PSI than that for this test. As long as the drop is proportional you've got a good MAP. There's another video similar to this but not done on an LT1 ( still GM car tho) by richpin06a that is very well done. Link is: kzbin.info/www/bejne/eGmoh5t8mJqMp9k

[@waltermiller249]

Thanks buddy!

[@FaisalAhmed-kf9yf]

How to check it without voltmeter ؟

[@darrelltalbott4830]

Thanks y’all