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Hello. I recently bought a 08 sky base with a mallet supercharger. Does anyone know if an OBD2 gauge would be able to pull boost? I was looking at getting either the Aeroforce interceptor 2 gauge combo or an Edge pro insight. I’m just not sure if I will be able to get a boost/vacuum number from a 2.4 ECU. Any help would be greatly appreciated
 

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Yes, you can read the MAP sensor, and quite a few other things, with an OBD gauge.
 

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Can he read boost pressure though on a 2.4L? I don't think the 2.4L has MAP sensors...does it? Just a MAF....right?
 

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Yes he can. You are incorrect, although it "only" has one (there is no boost sensor). No, it has a MAP and a MAF.
 

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Yes he can and as JohnWR mentioned, it is only a one-bar MAP sensor which will only read up to ambient pressure and into vacuum (negative pressure)

That's IF it's a stock MAP.

With the supercharger it has to be tuned as well and they may have put in a 2 or more bar MAP. If they have, then they had to set it up in the tune and IF they did this, the OBDII will read the boost values.

wjk221, I would get a bluetooth enabled OBDII scanner. You can get them on eBay for under $10. Then download the Torque app for android devices. This is free. (There is a pro version but you won't need that) This can read your MAP sensor and tell you if it will see only vacuum (negative numbers) or if it has been changed to read boost.

This also works as a code reader if you ever get a check engine light.
 

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Yes he can and as JohnWR mentioned, it is only a one-bar MAP sensor which will only read up to ambient pressure and into vacuum (negative pressure)

That's IF it's a stock MAP.

With the supercharger it has to be tuned as well and they may have put in a 2 or more bar MAP. If they have, then they had to set it up in the tune and IF they did this, the OBDII will read the boost values.

wjk221, I would get a bluetooth enabled OBDII scanner. You can get them on eBay for under $10. Then download the Torque app for android devices. This is free. (There is a pro version but you won't need that) This can read your MAP sensor and tell you if it will see only vacuum (negative numbers) or if it has been changed to read boost.

This also works as a code reader if you ever get a check engine light.
The DDM SC kit includes a new MAP sensor, and I have to assume that the Mallet conversion would as well.
 

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Why not get a dedicated boost gauge? They are inexpensive and typically very easy to install. I realize you are looking at specific gauge packages, IMHO boost pressure is one I would want "on" all the time to monitor.
 

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The DDM SC kit includes a new MAP sensor, and I have to assume that the Mallet conversion would as well.
I try not to ASSuME. Lol

Why not get a dedicated boost gauge? They are inexpensive and typically very easy to install. I realize you are looking at specific gauge packages, IMHO boost pressure is one I would want "on" all the time to monitor.
Usually the OBDII gauges let you monitor multiple PIDs like intake temps, fuel trims and knock. In a conversion like this, monitoring knock can be beneficial.

I have a boost controller and gauge in my car because it's a turbo conversion and the controller is required (kinda) to operate the turbo properly. With a supercharger, the pulley size controls boost level so a controller is necessary and a dedicated boost gauge/controller is less critical.
 

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I try not to ASSuME. Lol ........
You are correct, and I normally do the same, so let me start over.
Hello. I recently bought a 08 sky base with a mallet supercharger. Does anyone know if an OBD2 gauge would be able to pull boost? I was looking at getting either the Aeroforce interceptor 2 gauge combo or an Edge pro insight. I’m just not sure if I will be able to get a boost/vacuum number from a 2.4 ECU. Any help would be greatly appreciated
Your car does have a MAP sensor that is read by the ECM, but as Robotech stated, the stock sensor is 1-bar and will not measure boost. If Mallett changed it to a 2-bar or 3-bar sensor you will be able to read boost with a OBD2 gauge. My DDM conversion came with a 2-bar sensor, but I am not familiar with the Mallett. Read the part number from the MAP sensor in the car, and look it up to see what its rating is. If it is 2-bar or more you are good to go.

For the OBD-bluetooth converter I recommend something better than the $10 ones you get on Amazon, unless you are only ever going to run gauges with it. Many of them are too slow for data-logging, especially for more than one parameter. Do some research and be prepared to spend a little more.
 

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You are correct, and I normally do the same, so let me start over.

Your car does have a MAP sensor that is read by the ECM, but as Robotech stated, the stock sensor is 1-bar and will not measure boost. If Mallett changed it to a 2-bar or 3-bar sensor you will be able to read boost with a OBD2 gauge. My DDM conversion came with a 2-bar sensor, but I am not familiar with the Mallett. Read the part number from the MAP sensor in the car, and look it up to see what its rating is. If it is 2-bar or more you are good to go.
I also reached out to Chuck on FB so I'll see if I get a response from him. Even if the OP's car has a multi-bar sensor, it might be something the previous owner added later. Would like to know what a Mallett supercharger kit is supposed to come with.

For the OBD-bluetooth converter I recommend something better than the $10 ones you get on Amazon, unless you are only ever going to run gauges with it. Many of them are too slow for data-logging, especially for more than one parameter. Do some research and be prepared to spend a little more.
Agreed though most use them for error codes and gauges only. The cheap ones just will not have the speed to data log properly. They'll do it, but the log is so blocky that it is useless to get any meaningful picture of what's going on from it. Think trying to run one of today's computer games on an Atari 2600...LOL
 

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Yeah, it HAS to have a MAP sensor capable of reading boost or else it would run extremely poorly. I would definitely recommend what Robo said and just pay a few dollars to check it with the torque pro. I have pics on here somewhere showing what I was able to do for guages on a dedicated tablet. I can read KR, Intake temps, Boost, and RPMS all on the same screen.

It will even mark the highest and lowest numbers on each gauge which really comes in handy (like for instance when I wasn't looking at the IAT2 numbers closely, but it showed me my IAT2s got to a high of 130 degrees, or showing me the highest KR I would see on a run).

Also, to the OP....Please post a bunch of pics of your car!!!!
 

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Yeah, it HAS to have a MAP sensor capable of reading boost or else it would run extremely poorly.
IIRC, the ECM logic in the LE5 doesn't use the MAP for fueling or timing (nor I believe does the LNF but I don't know much about the Direct Injection logic). Fueling is all MAF based. I know adding a multi bar MAP sensor was an option when I went turbo...I mean it wasn't optional for ME but that's just me. LOL
 

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IIRC, the ECM logic in the LE5 doesn't use the MAP for fueling or timing (nor I believe does the LNF but I don't know much about the Direct Injection logic). Fueling is all MAF based. I know adding a multi bar MAP sensor was an option when I went turbo...I mean it wasn't optional for ME but that's just me. LOL
Yeah the LNF definitely uses it. I have some error codes to prove it. Based on the readings for the MAP it can push it to a different tune or not....

Also....I posted that pic for the plate you and JohnWR wanted to see....Check it out in my "Best Technique For Launching Off Of 2Step" thread then let me know if you understand what it is......
 

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Yeah the LNF definitely uses it. I have some error codes to prove it. Based on the readings for the MAP it can push it to a different tune or not....

Also....I posted that pic for the plate you and JohnWR wanted to see....Check it out in my "Best Technique For Launching Off Of 2Step" thread then let me know if you understand what it is......
I know the LNF uses it to determine boost levels and can put the car into limp mode if it's off but I was unaware it could put it into a different tune. Also I saw that picture and am unfamiliar with it. I have only had early 2007 NAs.
 

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I know the LNF uses it to determine boost levels and can put the car into limp mode if it's off but I was unaware it could put it into a different tune. Also I saw that picture and am unfamiliar with it. I have only had early 2007 NAs.
Yup!

Mine has the typical MAP error code which throws it into a different tune. The wierd thing about it is that my car was doing this random thing before the CEL where it would jump from 12 degrees advance to 6 and back after 5000rpms. That was verified by Trifecta. So after the CEL it put it into a different tune where it doesn't do that, and the car pulls really hard actually....It's strange as all.

Regarding the plate....Yeah that plate came standard on my 2007 Redline which allowed it to bolt to the torque arm. That plate definitely wasn't integral on the diff.
 

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Yup!

Mine has the typical MAP error code which throws it into a different tune. The wierd thing about it is that my car was doing this random thing before the CEL where it would jump from 12 degrees advance to 6 and back after 5000rpms. That was verified by Trifecta. So after the CEL it put it into a different tune where it doesn't do that, and the car pulls really hard actually....It's strange as all.

Regarding the plate....Yeah that plate came standard on my 2007 Redline which allowed it to bolt to the torque arm. That plate definitely wasn't integral on the diff.
What is the code that puts you into a different tune?
 

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Yup!

Mine has the typical MAP error code which throws it into a different tune. The wierd thing about it is that my car was doing this random thing before the CEL where it would jump from 12 degrees advance to 6 and back after 5000rpms. That was verified by Trifecta. So after the CEL it put it into a different tune where it doesn't do that, and the car pulls really hard actually....It's strange as all.

Regarding the plate....Yeah that plate came standard on my 2007 Redline which allowed it to bolt to the torque arm. That plate definitely wasn't integral on the diff.
What is the code that puts you into a different tune?
It's the P0107.
 

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Yup!

Mine has the typical MAP error code which throws it into a different tune. The wierd thing about it is that my car was doing this random thing before the CEL where it would jump from 12 degrees advance to 6 and back after 5000rpms. That was verified by Trifecta. So after the CEL it put it into a different tune where it doesn't do that, and the car pulls really hard actually....It's strange as all.

Regarding the plate....Yeah that plate came standard on my 2007 Redline which allowed it to bolt to the torque arm. That plate definitely wasn't integral on the diff.
I've not heard that an error throws you into a different tune but rather triggers certain modifiers that GM refers to as a "safe" mode...and there are at least a couple different ones pending on what the error is. The LE5 has one (kinda) that will shut off your AC Compressor if your coolant temps are over 250...not a different tune but a modifier.

The one I know of on the LNF is the one that opens the waste gate actuator solenoid so that boost control is handled completely by the actuator spring and boost level is kept to 6 psi or less. KR is a similar kind of modifier where timing is reduced based on KR level.

What it sounds like you are talking about is like the Trifecta "switch" between two tunes. Does this mean the LNF ECM has more than 2 tune options within it?
 

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There is no mention of an alternate tune in the service manual, and (oddly) no indication of what action that fault will cause.
The fault itself is a sensor reading that is out of range low, indicating either a bad sensor or a wiring problem.
 

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There is no mention of an alternate tune in the service manual, and (oddly) no indication of what action that fault will cause.
The fault itself is a sensor reading that is out of range low, indicating either a bad sensor or a wiring problem.
Yea that certainly wouldn't be a "different tune". LOL
 
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