3 bar MAP pid help

[RonSSnova]

Hi,

I have my 3 bar OS loaded to my PCM.
I've connected the scanner, and added the Manifold Air Pressure 3 Bar
Key on, it reads 0 kpa
The Manifold Absolute Pressure still in the table reads 104 kpa. Which is close, I have not adjusted the offset yet.

I am assuming that the Manifold Air Pressure only measures boost?
And the Manifold Absolute Pressure reads both boost and vacuum?

Or am I doing something wrong here?

I am wanting to start the car for the first time tomorrow.......

Thanks

Ron

[Chevy406]

Ron,
I just randomly clicked on this forum tonight and saw this post from you. I'll attach the scanner config I use for my Nova at the dragstrip with the 3-bar MAP sensor.
I setup the MAP Sensor Linear to 305.00 kPa and the MAP sensor offset = 6.00 kPa.

I'm not really sure how to answer your question about what should be showing with key on but engine off. I can't try it on my car right now because I have fuel lines pulled off. But I do seem to remember showing 0 kPa is normal until the engine is started.

Awesome that you are ready for first fire tomorrow. Looking forward to hearing some results.

Clyde

[RonSSnova]

Hey Clyde. You must have ESP? I only have ESPN.......
Thanks for the info. My config is set up nearly the same as yours.
I was going to mess with the offset and get it to read baro with key on.
I have a map like the ones Dsteck makes.
I know it's working, the volts are correct.

So cool!

I have the E85 in the tank, need to check for leaks, set the fuel pressure and see what happens!

Ron

[chevyalltheway]

Just out of curiosity, you are not logging multiple map pids in your table are you? I am on a 2 bar setup and I know when I first started using 2 bar that having my regular map and my 2 bar map pids on my table messed me all up. Food for thought.

[RonSSnova]

Since its just data, I will simply observe during my first start.
I'm having trouble understanding why the 3 bar map reads 0 and the std map pid reads correct with the key on.

[chevyalltheway]

Try removing the standard pid. Just use the three bar pid. Scanning both at the same time could confuse the scanner.

[RonSSnova]

Ok.
I'm now told by an experienced tuner that the 3 bar PID should read atmospheric with the key on, same as the std PID. So I'll need to figure this out.

Confuse the scanner? How about more like confuse the already confused operator?
:-)

[chevyalltheway]

Lol. After you try it Lemme know. I only suggest this because I had the same problem, this was the fix.

[RonSSnova]

Working on it. I'll let you know how it works out.
Had a fuel leak at one Teflon hose end and a failing optima batt anyway, so it's been a frustrating day.

[Russ K]

The 3 Bar Map Pid will read 0 Kpa key on engine off.

Russ Kemp

[RonSSnova]

Thanks. I figured that. It's odd though. Not intuitive.
Ron