PP6 MAP Sensor and Deflection Issues

[Stanky Leg]

I just installed my PP6, along with 550cc injectors. I have been running a TD04, and continue to do so. I do not currently have MAP deflection set up, and have been told not to use my TPS sensor as a replacement for MAP deflection sensor. I have been informed that i can buy a MAP sensor calibrated for the PP6, but i am at a loss as to where i can get one of these. This is what i could find about calibrating MAF/MAP sensors. Although it doesn't seem to be much help...

http://kniggeperformance.com/Sensor%20Calibration.pdf

If anyone can offer some useful information it would be greatly appreciated. So far Macipusy has been more than helpful offering information.

[Stanky Leg]

So, i am debating purchasing a generic MAP sensor at the auto parts store, and then calibrating it with the PP6. Does anyone know if this will work either?

[Legacy777]

What boost are you looking to run? You can calibrate the PP6 with the stock MAP sensor.

Can you elaborate about your title? Are you planning to eliminate the MAF sensor? With the PP6, you really can't do that. You still need the factory ECU with the PP6 and since the fueling is based off of the MAF sensor, and the response curves are completely different between MAP & MAF sensors, you can't just use the MAP sensor to control fueling.

Could you get the engine to run....possibly, but it's not going to be right, and you'll be fighting the tune and ECU.

[macipusy]

He is thinking of installing a separate MAP sensor for the deflection signal only....instead of using the TPS signal as deflection.

I am running a SMT6 MAP with my PP6 which uses the manifold pressure as load.

[Stanky Leg]

I know i need both a MAP and MAF sensor. All i need to know is where i should get a MAP sensor (if a generic one will work, they sell MAP sensors for Turbo cars at Advanced Auto parts) I do not want to use the TPS signal for deflection as many people appear to do.

EDIT. I would like to run about 16 pounds of boost, as i am tuning it for e85.

[macipusy]

I just did some research, and I think the SMT6 MAP sensor is 2.5 Bar. I would think a generic 2.5 Bar MAP with a 3 wire harness should work fine.

On my car I have it wired as follows:

The power for the MAP is teed in to the PP6 power wire - Red
The ground for the MAP is teed in to the PP6 ground - Black
The signal for the MAP is connected with the deflection signal on the PP6 - Brown

[Stanky Leg]

Awesome!!!! It will feel so good to have this done. Thank you soooooo much! You have been very helpful. I will keep you updated. But for now, it's off to advanced auto parts to see if i cant find one of these!

[Stanky Leg]

So, i had to order a MAP sensor. I got the GM 3 BAR in the mail today, and installed it. NEW ISSUE!!! After putting on a basemap, my car now only runs for about 5 seconds, then dies. The PP6 is telling me that as soon as i start my car, the deflection instantly goes to 96.1%. It is as if the deflection is backwards, as at about 600 RPM, i believe i should have a deflection value of about 2.8%. Does anyone have any advice?

[macipusy]

It does seem like the deflection is reversed. In the Scale Settings>Deflection check the current settings.

Mine are set to Min-Max and min is at 7.8% and max at 90.2%.

[Stanky Leg]

I have done that, and my settings are the same as yours. For some reason the deflection instantly goes to 96.1%... It doesn't make sense. haha I have heard that the deflection can be backwards and needs to be flipped... i just don't remember where i read that. And don't know how... Anyone?!?!

[Stanky Leg]

Ok.... So... We tried to enter in your numbers and see what happened. The car ran for about 5 seconds, then died as usual. Then, we did the same thing, only this time i gave it some gas. It worked, and now the car will idle. However, the check engine light came on (no surprise) and the car will not rev over 2000 RPM. So we tried using the jumper plug to see what would happen... no change. It idles on its own now, but wont go above 2000 RPM. So, what do you think? My theory is that the car is running so rich, that it will not go above 2000 RPM from sheer too much gas... We made sure the fuel calibration was set to -10 each time... I'm happy it will idle. Now to get it to go...

[Boxman]

I am helping the OP with this project...

The deflection is definitely flipped though. When we rev it, the deflection goes down. I am not sure if the AFR value was correct, but when it was idling it was only at 11.6 or so. Based on the map and injectors I can't imagine that that is correct. Along with the fact that it reeked of gas after we ran it for a minute. I am very curious to see if anybody has an idea on the 2K rev limit. A wideband would be incredibly helpful though.

[Boxman]

Another question, is there a good way to leave the ignition in the ON position without frying the coil pack/ignitor? Like to change the map or to read the CEL for instance. Or do you just have to hope they don't fry? Thanks!

[macipusy]

You can leave the ignition in the on position if you unplug the ignitor....but it is a pain in the ass if there is a TMIC.

If it reeks of gas....then 11.6 AFR at idle is not out of the question. Reduce the value in the idle cell and see what happens to the AFR.

As far as the reversed voltage MAP, you might just have to tune in the opposite direction....should be no problem. I know the VW guys have to do it reverse when using TPS as deflection, since they have a reverse voltage TPS.

[Boxman]

Wouldn't it reek of gas because it's running incredibly rich? I have been told to try to reduce the amount of gas by my tuner as well so we are going to try that. The thing that is so confusing is that it won't rev past 2000 rpm... The only thing I could think is that it is so rich that is just gets choked by the gas. Any other ideas folks? Thanks for your opinions so far!

[Stanky Leg]

Just pulled the code. Came up as 22, knock sensor. So sounds like it could be an ignition problem... We are going to try to pull some timing out of it... We also reduced the analog numbers by a little and it won't idle at all now.... This would all be so much easier with a wideband.

[macipusy]

11.6 at idle is rich....but I would not rely on the narrowband reading for AFR accuracy. Swap out the knock sensor and see what happens.

BTW the car will start choking out at about 9 - 9.5 AFR from too much fuel.

[Stanky Leg]

Good to know. Thanks a lot, and i'll try that. I really need a wideband. Hopefully Eric can come help me out soon.

[Legacy777]

Check out my post about calibrating the MAP sensor for deflection. Not sure if you saw it yet.

http://www.bbs.legacycentral.org/viewto ... &start=200

[Stanky Leg]

Thank you Legacy777. I will follow that and let you know. I have been so busy with school and work (much harder without my car running) that I haven't been able to work on it. I have tried so many things, and really need someone who knows what they are doing. Its about time to call in the cavalry on this one.

[Boxman]

Well we decided to take the injectors out today. Put in the "revert to stock" thingy into the PP6, and the car runs fine. We had one of our local tuners come out and try to mess with it. Turns out no matter what we did with the Analog map it wouldn't change the fueling at all... It would start up differently if we changed things, but otherwise it would run the same. We have no idea as to what has happened. The AFRs were always the same and it would never rev over 2K, so without a PP6 expert we will never know. Such a bummer.

[macipusy]

I can come take a look...but I will not be back in town till the end of next week.

You guys should try to get it running via TPS in the meantime.

[Stanky Leg]

So i've got her running again. Today marks the first day of no leaks or issues. The PP6 is still non-functioning, and the stock injectors are back in. Thanks Macipusy for all your help. Let me know when you are back in town. As for the TPS, i thought about trying it, and probably will sometime in the upcoming days.

[Legacy777]

Wait.....you guys are trying to modify fuel, but were using the MAP sensor as the analog deflection correct? If so, that's not going to work. These ECU's are MAF based and that signal is what is used to adjust fuel. If you hook up the PP to intercept the MAF signal, you will be able to modify fuel.

[macipusy]

They were using the MAP sensor as a deflection signal only, instead of the TPS signal.

The PP6 thinks its getting a voltage reading from the TPS but the voltage reading is actually measured by manifold pressure on the MAP. Both of these should be a 0-5v signal.

I think the Subaru TPS sends a higher voltage when the throttle is closed. The MAP you have reads a higher voltage at a higher pressure, therefore causing the issue of reading 92% load at at idle.

It might be possible to reverse the voltage by reversing the wires...but I'm not positive.