I was wondering if there was a certain vacume port to hook the map senser to on a series 4 intake manifold? I was wondering because my car will idle but when I give it a little gas, it dies. I can't drive it. I was thinking maybe it's hooked up in the wrong place. My microtech hasn't been tuned but does have a map made by Jon at RX engineering during that big group buy a few years back so I think it should be driveable.

thanks

 

IIRC it's the lower nipple on the front of the TB closest to the alternator...

 

Any of the nipples on the front of the throttle body are fine. The ones at the back are atmospheric. If you have accidentally used them, the Microtech will be very confused.

Avoid the nipples that only take a signal from one intake runner like the boost/pressure sensor. The signal is very dirty, hence the need for Mazda to run a restricter pill.

 

The critical issue here has to do with choosing a source that is not 'pulsy' from reversion in the intake runners. The pulses wlil be reflected in the output of the MAP sensor. That's not good news.

Pick a source in the plenum/surge tank portion such as one of those vacuum nipples on the front of the UIM that's already been suggested. The signal will be much smoother. Don't use the nipples on the firewall side.

B

 

Thanks guys! I hope that's my problem. I had the line hooked up to the bottom nipple on the firewall side! I'll move it tonight and let you know the outcome!

 

Ok, I got her running! I took one lap around my street. It was late and I only have a down pipe on there! No exhaust yet. Anyways, I did move that vacume line to the bottom nipple closest to the alternator.
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That actually wasn't my problem. (this is a first gen btw). For some reason, the way my friend wired my fuel pump into the microtech was causing the fuel pump to shut off once the key is turned to start the car! So it would idle for a few seconds from the excess fuel, then die. Anyways, we cut that green wire for the microtech and let the stock wiring take care of the fuel pump and now it drives!

He's gonna try and figure out the stock relay on another day and re wire it.

 

I just did away with the stock fuel pump wiring, and completely rewired mine, so that I know it won't fail on me on a full-throttle run. You probably wired up the relay incorrectly.

 

yeah that was my first problem when I got my lt8 tuned before. The boost was all over the place when data logging. As soon as I changed it to a better source all was well.

 

Yes, I think your right. Were gonna rewire everything when I put in my Bosch fuel pump after the motor is broken in and before it's tuned or driven hard. For now I am just running the stock 85 gslse fuel pump because I'm not planning to boost until I get this new motor broken in. I just kept the stock pump in there so that I would have one less thing to troubleshoot if the car didn't start