Hey all. I'm in the middle of an install of a PLX r-300 in my car. I have it in and it's working [separate write up to come, just gotta chase a couple of gremlins! ], but I have a question....

In order to interpret the analog signal coming from my MAP sensor, I need to map out the voltage readings at different pressures. I need the ability to convert voltage readings from the signal into pressure units, in order for the PLX controller to work its magic.

To do this, I see two options:
1) To read the voltage at idle [and set this as '0'] and read at some random load and let the computer fudge the response curve. <- Quick and dirty method [I don't really KNOW the pressure at any point without access to other obd-ii logging goodies...]
OR
2) To either find the manufacturer of our MAP sensor and then track down the specs on the sensor or to find someone who knows the specs already. <- The elegant way...

So, does anyone know the manufacturer and part number for the MCS's sensor? Does anyone know the specs on the sensor? How many bar? What will it read at ambient pressure? Under xyz load?

Or, does anyone have another idea of how I can approach this?

Thanks, in advance, for any help, and sorry if you've already read this in the Drivetrain Mods forum. I didn't know where this would best be put. Have a great one!

 

bump.

 

I know that my diagnostic readers show the MAP output simultaneously as a pressure and a voltage. This is read over the OBDII port. A down and dirty way to get a range of voltages would be to correlate readings with the key on and engine off (atmospheric), idling (a particular vacuum) and at some sort of steady boost, maybe 5 psi. You could extrapolate the linear relationship of voltage vs. pressure that way.

I am not sure, but I think the MAP is made by Seimens or Valeo.

 

Digging back up this old thread...

I'm planning a water/meth install, and the system I'm working with taps the MAP sensor to figure boost. My question is, what's the range of the 1st Gen MINI MAP sensor? From reading, seems that most manufacturers use a 2 bar (which would read boost up to 14.7psi at sea level) or a 3 bar (which would read up to 29.4 at sea level)... is the MINI MAP sensor like this, or does it use some custom range?

 

But IMHO, it would be easier to buy the MAP sensor the meth kit supplier sells and tap the boost. Especially since the MINI sensor tends to go south from time to time.

Does the kit manufacturer sell such parts?

 

Yep. They do... may end up going that route... but may try the OEM MAP tap first, just for thrills.

 

I'm planning a water/meth install, and the system I'm working with taps the MAP sensor to figure boost. My question is, what's the range of the 1st Gen MINI MAP sensor?

The Cooper S uses two sensors to measure boost; a MAP before the SC and a TMAP in the manifold. The range of the MAP is 17.4 PSI. The TMAP has a range of 36.2 PSI.

 

Hmmm... so sounds like TMAP (which is what I'd be using) has a range of 2.5bar... just curious frenchie - where did you get this info?

 

Actually, I'm pretty sure it's a 2.5bar, I didn't think that was the question. In reality what is the output range for the 2.5bar? Is it 0-5v over it's range, 1-5v, or 1-4.5v, etc. Testing the vacuum range would be harder(a brake bleeder would work well) but for the positive side you could perform a simple test. First measure the applied voltage by the car to the sensor so you know what it should be out of the car. Could be 12v, 13.5, 14, etc. Then take it out of the car, put a power source to it and map it for each PSI, 1,2,3,4 all the way to max, again it may be an odd reading at full range.

Simple, right. That's why I said it would be easier to buy the one that is offered as an option with the kit.

In reality the linearity and dynamic range of the kit you have(I'm making an assumption here) won't come close compared to the relative error you incur from the values you plug in for sensor range, so it's not that critical.

 

When my MINI was about 2 months (2002 R50) old I discovered that the company that prints all BMW training material was a 20 minute ride from my house; so I walked into their front lobby and purchase a manual titled "MINI Complete Vehicle" Technical Training Course #STO44. It is the exact document used to train the MINI technicians. It covers Body, Drive line, Engine Management, Body Electronics, chassis, Communication and Service. This is not a repair manual... but rather a theory guide on how / why everything works. In fact most of the illustrations found in the Bentley Manual (which I also have) are taken from this publication. The document actually list the max range of the TMAP as 250Kpa and 120Kpa for the MAP...I converted the value to PSI in the previous post. this does not mean that the vehicle will operate in this range.

A voltage reading of about .6 to 1.5 indicates high vacuum condition (idle or no load)....a reading of about 4 volts indicate low vacuum or full throttle. The ECU provides a bias voltage of 5vdc.... but above approx 4vdc is reserved for diagnostics ( the ECU will interpret this condition as an open circuit and throw a code immediately...a code will also be generated at the 0vdc as this would represent a shorted condition.

Hope this helps!

 

I wouldn't mind getting my hands on a copy of that manual. Any way to do so?

 

The name of the company is Central Letter Shop; they are a distributor for BMW dealer tools and they print the documentation for BMW as well. they are located in Fairfield N.J.

Try this link: https://infobase.apinet.com/API-Supp...e?Category=311

 

Thanks for the link.

 

Also check this site: it is provided by the manufacturer and made available to the public for a subscription fee, the training manuals are also available here along with all repair and TSB and a ton of other information for download in pdf if memory serves. The cost for 24 hour access is $30. The hard copy that I purchased set me back $100 in 2002.

http://www.minitis.com/