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5 minutes ago, Me78569 said:

what you need to know is in this thread.  it has directions for adding map readings and the equation to the app.

 

 

Looks like what I need to read the map then. 

Sobtonight I’ll go back over everything we’ve talked about and see what I come up with. Anything else to do?

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Remember the OBDLink will read a weird boost number. Like mine starts at 28.6 PSIa and goes to 37.7 PSIa. So it not going to help you figure out what's happening. Even my ScanGauge II does this very same problem.

 

Thing is you should never exceed 20 PSI period. Edge start boost fooling as low as 14 PSI. If the ECM is seeing above 20 PSI it will start to defuel as well. The P0234 code is typically tripped after about 23-25 PSI.

 

The only thing I could suggest is reading over the error codes P0234, P0236, P0237 and P0238...

 

 

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My truck is a 2000. 

55 minutes ago, Mopar1973Man said:

Remember the OBDLink will read a weird boost number. Like mine starts at 28.6 PSIa and goes to 37.7 PSIa. So it not going to help you figure out what's happening. Even my ScanGauge II does this very same problem.

 

Thing is you should never exceed 20 PSI period. Edge start boost fooling as low as 14 PSI. If the ECM is seeing above 20 PSI it will start to defuel as well. The P0234 code is typically tripped after about 23-25 PSI.

 

The only thing I could suggest is reading over the error codes P0234, P0236, P0237 and P0238...

 

 

Looks like all good reading but just curious why are you suggesting I read over the other codes other than p0237? Just fmi? I’ll defiantly look them over though! :wink:

I have a pretty good feeling that the p1694 and p0123 are from when I forgot to turn off the ignition when I plugged the ecm back in. I cleared the codes and they did not come back which is why I assume that. 

5 hours ago, Me78569 said:

what you need to know is in this thread.  it has directions for adding map readings and the equation to the app.

 

 

I find this extremely confusing! :doh: Is there a possibility you could type up all the values to be able to read the map? 

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48 minutes ago, Marcus2000monster said:

ooks like all good reading but just curious why are you suggesting I read over the other codes other than p0237? Just fmi? I’ll defiantly look them over though! :wink:

 

Because it gives all the wiring diagnostics and explains the limits of each type of error. In the same time you could verify your wiring and know if there is any wiring issues that might be there too.  Also might give you clues to isolating the issue at hand.

Edited by Mopar1973Man
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11 minutes ago, Me78569 said:

Please read the thread, I posted what you are looking for a few posts down.  

 

Going thru my obd app I see a sae pid that says intake manifold air pressure. Is this not what I’m looking for? 

9 minutes ago, Mopar1973Man said:

 

Because it gives all the wiring diagnostics and explains the limits of each type of error. In the same time you could verify your wiring and know if there is any wiring issues that might be there too.  Also might give you clues to isolating the issue at hand.

Right on Mike! I’ll be lookin over al my wiring also. Really do appreciate the help guys. :)

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Alright I have boost reading accurately for our trucks

 

 

Issue we have with our trucks is

 

early trucks read map values as 0-1023 or 0-5v 

late trucks read 0-255 and the ecm decodes that

 

our sensors read in KPA at least for early truck late trucks may read in PSI.

a KPA

 

Our sensors also do not take atmospheric pressure.  Our ECM takes the KPA from the map sensor then takes baro pressure and minuses it. 

 

 

So to configure on a early truck

 

Name: Boost

Description: Boost

Manuf: Generic

metric units: Units

english units: psi

min: 0

Max: 1023

Metric to english scale: .2

Metric to English offset: 0

header: 486

obd mode: 01

pid: 0B

Priority: high

equation: (A*.145)-16   ****16 is the approx of atmosphere so since I am high in altitude you take 14psi for sea level then add a few PSI for being high.  

 

So to configure on a late truck  ( untested but I think that should work)

 

Name: Boost

Description: Boost

Manuf: Generic

metric units: Units

english units: psi

min: 0

Max: 255

Metric to english scale: .2

Metric to English offset: 0

header: 486

obd mode: 01

pid: 0B

Priority: high

equation: (A*.145)-16   ****16 is the approx of atmosphere so since I am high in altitude you take 14psi for sea level then add a few PSI for being high.  

 

So using these numbers I statted the truck and ran this command and it came back with -2.71 psi. I don't have a splitter so I canr take it out and do that yet.

How do I sens commands in the Obdlink app??

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