Microtech Map Sensor?
#1
Full Member
Thread Starter
Join Date: Aug 2003
Location: Auburn, Washington
Posts: 112
Likes: 0
Received 0 Likes
on
0 Posts
Map Sensor?
Do microtech's have the map sensor in them, or is it separate? If it is separate, where is it? Also, if anyone has any pictures or diagrams of their install and all the vaccuum lines and wiring, that would be a huge help! thanks.
Last edited by AllTheTime; 08-23-03 at 01:26 PM.
#2
Round&Round not Up&Down
Join Date: Aug 2001
Location: West Bloomfield, MI
Posts: 2,805
Likes: 0
Received 0 Likes
on
0 Posts
The 2 bar map sensor is internal, but there is an optional 3 bar sensor that is external if purchased. The wiring is very easy, if you can follow diagrams and solder, then you can do it. I'll get pics up of my install some time tonight.
#5
Round&Round not Up&Down
Join Date: Aug 2001
Location: West Bloomfield, MI
Posts: 2,805
Likes: 0
Received 0 Likes
on
0 Posts
Originally posted by Ryde _Or_Die
How much is the 3D map sensor extra if purchased at the same time as the unit itself?
How much is the 3D map sensor extra if purchased at the same time as the unit itself?
Trending Topics
#10
My LT8 with internal sensor reads 5hg of vacuum even when the car is turned off. It reads 20hg when the car is idling, it's a 13b turbo with large streetport so that number is WAY off. I'm in the proccess of sorting out what to do with the thing.
#15
Originally posted by Piranha
do you mean 3 bar? The Microtech is in 3D with the 2 bar or 3 bar, the 3 bar just lets you run over 20 PSI.
do you mean 3 bar? The Microtech is in 3D with the 2 bar or 3 bar, the 3 bar just lets you run over 20 PSI.
#17
Originally posted by jimmyv13
Well, Calgary is 3556 ft above sea level, so I'm guessing that will mess with your vac reading pretty good.
Well, Calgary is 3556 ft above sea level, so I'm guessing that will mess with your vac reading pretty good.
It's not the end of the world I will just have to tune it knowing it's a bit off, kind of annoying.
#18
Round&Round not Up&Down
Join Date: Aug 2001
Location: West Bloomfield, MI
Posts: 2,805
Likes: 0
Received 0 Likes
on
0 Posts
Originally posted by silverrotor
The vacuum line, running from the ECU to the Engine Bay, should have an uninterrupted source at the bottom (of the 3 nipples), front Upper Intake Manifold.
The vacuum line, running from the ECU to the Engine Bay, should have an uninterrupted source at the bottom (of the 3 nipples), front Upper Intake Manifold.
#19
Rotary Enthusiast
Join Date: Aug 2001
Location: Tallahassee, FL
Posts: 1,402
Likes: 0
Received 0 Likes
on
0 Posts
That source will work fine, but the front-bottom is the best. That source comes right from the back of the throttle plates, and will result in the best response, as well as minimise erratic readings from intake manifold pressure waves.
Brandon
BR7 Racing
Brandon
BR7 Racing
#21
Rotary Enthusiast
Join Date: Aug 2001
Location: Tallahassee, FL
Posts: 1,402
Likes: 0
Received 0 Likes
on
0 Posts
The reason I like the front-bottom is that the black TB spacer directs the airflow to a little hole that's just behind the primary throttle plate on the engine side. This means that its readings are the best-damped, since they have the benefit of using the entire surge plenum to dissipate spikes. Jimmy's will work just fine; its reading is taken from the side of the plenum. It's really just a matter of preference. The only thing that I will discourage is readings taken from sources within the runners, e.g. the nipple right above the ACV. These readings tend to be quite erratic.
Brandon
BR7 Racing
Brandon
BR7 Racing
#22
Originally posted by No7Yet
only thing that I will discourage is readings taken from sources within the runners, e.g. the nipple right above the ACV. These readings tend to be quite erratic.
only thing that I will discourage is readings taken from sources within the runners, e.g. the nipple right above the ACV. These readings tend to be quite erratic.
#23
Originally posted by rx7_turbo2
That was my assumption as well. However I have friends with Wolf and Haltech who do not have this issue. Their units seem to calibrate themselves.
It's not the end of the world I will just have to tune it knowing it's a bit off, kind of annoying.
That was my assumption as well. However I have friends with Wolf and Haltech who do not have this issue. Their units seem to calibrate themselves.
It's not the end of the world I will just have to tune it knowing it's a bit off, kind of annoying.
#24
Senior Member
i see some GM 3 bar map sensor around $60
That is 0 volts at closed throttle and 5 volts at full throttle. It varies linearly in between those points. So all you need is a pressure sensor that reads 0 volts at the lowest pressure you'll see and 5 volts at a pressure a little above your maximum boost pressure. It needs to vary linearly in between those two points. The sensor must be able to survive in the harsh environment of an engine bay [high temperatures and dirty air]. Finding a sensor with all of these qualities is not easy, especially for a novice like me. After much searching, I did find the proper sensor. Its a Motorola MPX 4250 AP. It reads from 2.9 to 36.3 psia and gives a 0.2 to 4.9 volt output. It is actually designed to be used in turbocharged automotive MFI applications. You can get it from Newark Electronics for about $22. You'll need an enclosure to protect it. A little black box, 1551GBK, works nicely. You need several feet of high temperature 24 AWG wire. Three different colors is the best way to do it. That way, you know what wire is what. Tap-in connectors will also be needed. Radio Shack sells some with built in bullet connectors [for quick disconnects]. The part number is 64-3089. A crimp tool, zip ties, bullet connectors, soldering iron, solder, flux, drill, quick-cure plastic epoxy, and double sided foam tape will also be needed.
Building and installing
This is the easy part. Before anything else, get familiar with the sensor characteristics. Read through the specifications in this PDF file: MPX4250A.PDF. Be careful with the sensor. Don't touch the leads with your fingers. The sensor is labeled "static sensitive", so don't take chances. Now drill a 3/16" hole in the side of the box for the sensor port to stick out of. Drill the hole so that the sensor can sit against the bottom of the box. See picture below.
Solder a 1 foot length of wire to pins 2 and 3. Pin one is denoted by the notch in the lead. Solder a length of wire to pin 1 that is long enough to go from the sensor to your S-AFC wiring harness. Drill a 3/16" hole in the other side of the box for the wires to pass through. Drill a tiny hole in the top for an air vent. Thread the wires through the 3/16" wire hole in the box. Spread some plastic epoxy in the bottom of the box and lay the sensor in it. Make sure the vent hole in the sensor is up [you don't want to epoxy it shut]. Push the port of the sensor though the port hole as far as it will go. Use some more epoxy around the port hole. You need to hold the sensor in place while the epoxy cures. If you shopped wisely, it'll only take 5 minutes. Once the sensor is secured, you can screw the top on. You can use the foam tape to attach the sensor to something in the engine bay [preferably something cool]. Mine is on my cruise control box. Use the tap-in connectors to tap into the 5 volt power and ground for the stock MAP sensor. It is very important that you use these two connections from the stock wiring. The voltage is very stable here. Sensor output is related to its power source.
Her's the link http://www.2gnt.com/www/corbin/foolafc.html
#25
Moderator
iTrader: (1)
Originally posted by rx7_turbo2
My LT8 with internal sensor reads 5hg of vacuum even when the car is turned off. It reads 20hg when the car is idling, it's a 13b turbo with large streetport so that number is WAY off. I'm in the proccess of sorting out what to do with the thing.
My LT8 with internal sensor reads 5hg of vacuum even when the car is turned off. It reads 20hg when the car is idling, it's a 13b turbo with large streetport so that number is WAY off. I'm in the proccess of sorting out what to do with the thing.