p0108 error code help
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Senior Member
Joined: Feb 2010
Posts: 118
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From: Rockledge, PA
Vehicle: 02/Hyundai/Elantra GLS
ok so I finally got my car turboed (stupid oil leaks) and it runs great however the other day I had it out for a little just to drive it and not beat on it and it threw a CEL for P0108 which is Manifold Absolute Pressure/Barometric Pressure Circuit High Input. im thinking I prob need a tune or a new MAP sensor which ill get tomorrow off the bat but I was wondering if anyone knew of a solution to this or if my guess is just correct and I need a tune.
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Joined: Mar 2006
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From: Lacey, WA
Vehicle: Two Accents, Mini, Miata, Van, Outback, and a ZX-6
Ok, logic would dictate that the sensor would give an out of range reading considering that the ECU mapping was never intended to compensate for pressure beyond atmospheric pressure.
And yes, you need a tune. For sure.
And yes, you need a tune. For sure.
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Joined: Sep 2001
Posts: 10,795
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From: Pflugerville, TX
Vehicle: 2000 Elantra
If you are running around on with a turbocharger and no tune, you are driving a time bomb. Get it tuned because it needs a tune, not because of check engine codes. The codes go away when the tune is done right.
A voltage clamp would stop the code, but would do nothing to stop the fuse for the blown motor bomb you have going. The stock MAP can handle about 4psi based on its range according to the EXD guys.
The problem with the clamp. pressure keeps rising and lets say you use a clamp to not let it exceed 4.8vlts and lets assume that is 4psi. Once it crosses 4 psi the voltage would no longer rise from the sensor because the clamp is killing anything over 4.8 volts. So no code, but not extra fuel is being sent into the engine by the ECM because it has no way to know its there. 4.8 volts means X air to it. Lean condition and one other bad thing happening... bye bye ring islands.
(note: some XD guys saw the cell at anything over 4.6 volts.. when others pushed to 5. Might be the type of clamp and what it is really doing? maybe).
http://www.splitsec.com/products/vc2/VC2.htm
The MUCH better solution is the GM 3 bar and tune it so the engine knows what the hell it means by 1vlt since the ECM will think it has a hell of alot more air than its really getting with 1vlt from the 3 bar when compared to 1vlt from the stock MAP. Then.... what to use to fix that? Gonna have to research that one.
The problem with the clamp. pressure keeps rising and lets say you use a clamp to not let it exceed 4.8vlts and lets assume that is 4psi. Once it crosses 4 psi the voltage would no longer rise from the sensor because the clamp is killing anything over 4.8 volts. So no code, but not extra fuel is being sent into the engine by the ECM because it has no way to know its there. 4.8 volts means X air to it. Lean condition and one other bad thing happening... bye bye ring islands.
(note: some XD guys saw the cell at anything over 4.6 volts.. when others pushed to 5. Might be the type of clamp and what it is really doing? maybe).
http://www.splitsec.com/products/vc2/VC2.htm
The MUCH better solution is the GM 3 bar and tune it so the engine knows what the hell it means by 1vlt since the ECM will think it has a hell of alot more air than its really getting with 1vlt from the 3 bar when compared to 1vlt from the stock MAP. Then.... what to use to fix that? Gonna have to research that one.
Thread Starter
Senior Member
Joined: Feb 2010
Posts: 118
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From: Rockledge, PA
Vehicle: 02/Hyundai/Elantra GLS
I know I need to change the engine management I'm working at 1 thing at a time I'm not gonna tune the car then put a fuel pump injectors and a 3 bar map to just have to tune the car again. This is also y I don't drive the car


