Post by thread:Vaccum sensors/switches

How might I interface a vaccum system to a pic? Does anyone make sensors that can be used to detect various levels of vaccum, like some automotive sensors do? My goal is to replace some extinct vaccum switches and sensors in my old chevy to make the system more configurable, and controllable, like some of the really expensive performance carb systems do. Steve

On Thu, 4 Dec 1997, Steven J Tucker wrote: > How might I interface a vaccum system to a pic? Does anyone make > sensors that can be used to detect various levels of vaccum, like > some automotive sensors do? Check out Motorola. I am using their 2.5 Bar MAP sensor. This sensor goes up to 22 psi for Turbocharged applications. > > My goal is to replace some extinct vaccum switches and sensors in my > old chevy to make the system more configurable, and controllable, like some > of the really expensive performance carb systems do. Motorola has a wide range of sensors. -Dave Celsnak

Steve, how old a Chevy? Do you want switches or analog sensors? Are you talking about "vacuum" advance? You will need a pressure sensor/switch. Sensym and Motorola have a variety of sensors. If by "old", do you mean 1955/56? If so, I might want to buy it ;-) - Tom At 01:24 AM 12/4/97 -0500, you wrote: {Quote hidden}>How might I interface a vaccum system to a pic? Does anyone make > sensors that can be used to detect various levels of vaccum, like > some automotive sensors do? > >My goal is to replace some extinct vaccum switches and sensors in my > old chevy to make the system more configurable, and controllable, like some > of the really expensive performance carb systems do. > >Steve > >

Steven J Tucker wrote: > > How might I interface a vaccum system to a pic? Does anyone make > sensors that can be used to detect various levels of vaccum, like > some automotive sensors do? > > My goal is to replace some extinct vaccum switches and sensors in my > old chevy to make the system more configurable, and controllable, like some > of the really expensive performance carb systems do. > > Steve A standard chevy MAP sensor outputs 0 - 5v over 0"hg to 30"hg. They are $30. PR

Steve, As another message indicated, you can use a common automotive MAP sensor, which has the advantage that it is designed for the harsh environment in the engine compartment. My favorite is the Mitsubishi Mirage sensor, MD178243, which sells at the dealers for approx ten bucks! It has three pins: +5.0v, GND, and signal out. The output voltage is 4v at 1 atmosphere, decreasing to approx 0v at complete vacuum. I was playing with one earlier tonight, in fact! This particular MAP sensor (unlike some others) also has sufficiently quick response to allow observation of the individual vacuum pulses from each cylinder as the engine is running. This can be a great diagnostic tool for bad valves, cam lobes, etc. I have more info on that subject if anyone is interested. Oh... you can also get the Mitsu sensor at Dodge dealers (probably any Chrysler outlet, actually) since they sold the Mirage under a different name (Summit??). Same part number works. Randy ---------- {Quote hidden}> From: Steven J Tucker <.....classicsKILLspam@spam@NACS.NET> > To: PICLISTKILLspamMITVMA.MIT.EDU > Subject: Vaccum sensors/switches > Date: Wednesday, December 03, 1997 10:24 PM > > How might I interface a vaccum system to a pic? Does anyone make > sensors that can be used to detect various levels of vaccum, like > some automotive sensors do? > > My goal is to replace some extinct vaccum switches and sensors in my > old chevy to make the system more configurable, and controllable, like some > of the really expensive performance carb systems do. > > Steve

Randy Jones wrote: {Quote hidden}> > Steve, > > As another message indicated, you can use a common automotive MAP sensor, > which has the advantage that it is designed for the harsh environment in > the engine compartment. My favorite is the Mitsubishi Mirage sensor, > MD178243, which sells at the dealers for approx ten bucks! It has three > pins: +5.0v, GND, and signal out. The output voltage is 4v at 1 > atmosphere, decreasing to approx 0v at complete vacuum. I was playing with > one earlier tonight, in fact! This particular MAP sensor (unlike some > others) also has sufficiently quick response to allow observation of the > individual vacuum pulses from each cylinder as the engine is running. This > can be a great diagnostic tool for bad valves, cam lobes, etc. I have more > info on that subject if anyone is interested. > > Oh... you can also get the Mitsu sensor at Dodge dealers (probably any > Chrysler outlet, actually) since they sold the Mirage under a different > name (Summit??). Same part number works. > > Randy > I am very interested in all the info you have. The price is awesome. e-mail direct is you feel it is appropriate PR