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MAP Sensor Failure and Engine Misfire

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Old Oct 6, 2006 | 08:13 AM
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Default MAP Sensor Failure and Engine Misfire

Put new Heads (Patriot 243) and new cam (Thunder racing .594/.228 112 LSA) in and computer is showing engine misfire and MAP Sensor failure. I changed the MAP Sensor and still get the same code. I even swapped out the PCM from another T/A and still threw the same codes. I am only putting out 335 HP off of this set up when it should be a whole lot more considering that I had 329 HP STOCK!!! Please help I'm at a loss.
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Old Oct 6, 2006 | 08:20 AM
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By the way I changed the plugs I am running TR6's I also changed the plug wires and I checked all the wires going to the PCM and going to the MAP sensor and nothing?!?!?
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Old Oct 6, 2006 | 08:49 AM
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Maybe your cam was installed off a tooth or two
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Old Oct 6, 2006 | 09:01 AM
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Wouldn't that cause my engine to run badly??? It runs nice just not producing the numbers I want. Idles at about 850 to 900 rpms steady.
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Old Oct 6, 2006 | 09:59 AM
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Don't you always get a misfire code after a cam install? I know my car ran like *** until it was tunned properly.
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Old Oct 6, 2006 | 10:04 AM
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I just had this problem.Bent intake valve is what we had.
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Old Oct 6, 2006 | 12:04 PM
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Shouldn't there be a ticking noise if that is the case cause there is no noise.
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Old Oct 6, 2006 | 12:21 PM
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Did you mechanicaly over-rev?
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Old Oct 6, 2006 | 12:27 PM
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when i did my 408 i would get those codesall the time... get the car tuned better.. once i got a tune it never threw them again.
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Old Oct 6, 2006 | 12:32 PM
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What do you mean by mechanical over rev?
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Old Oct 6, 2006 | 12:46 PM
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Originally Posted by dixonk
What do you mean by mechanical over rev?

he means did you miss a shift, like going from 3rd gear down into second gear, or 4th to 3rd instead of 4th to 5th.

an mechanical over rev can not be helped by the computer... the rev limiter just cuts fuel.. but if you miss a gear is PHYSICALLY pushes your motor to exteremely high RPM's
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Old Oct 6, 2006 | 01:07 PM
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No I definetely never did that. What I did was as soon as the parts where put in I let in run and learn for about 20 minutes then I took it around the block not running it hard at all and then straight to the dyno for tuning. From the very beginning since the install I've had the SES light flashing and misfire and MAP codes. I also had a TPS and O2 codes but I replaced them and those codes went away.
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