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Desperate need of help CRF 450R 2009

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I have a CRF 450 2009 when I bought it it started very easy, but all of a sudden I could just start and then it stopped, I got an error code that said MAP sensor circuit mail function.
the problem was that the fuel filter was clogged, I cleaned the filter and then it was ok again that race.
after a while the bike began to be difficult to start hot or cold, I tried to remove the fuel filter and it was a little better, I bought a new filter an insalled it, but it continues to be difficult to start .
I measured the fuel pressure it was 50 psi and it held the pressure when I turned off .
This spring I continued to look for what is wrong and then noticed that the fuel pump not keeping pressure anny more when I turned off .
I bought a new fuel pump but it is still hard to start, I took off the spark plug and checked the spark I get a spark the first two kicks then nothing if I just depress the kick slowly I get a little spark , I tried a different spark plug same thing. I put the spark plug back and tried to start, all of a sudden it starts easy now , I tried 10-15 times and it strart up directly then I touched the wires at the throttle housing and now I get the same error again MAP sensor circuit mail function, the engine also runns worse at lowidle now than it did when I did´t get error codes.
I wonder if it gets too little fuel or if the injector is bad, I've had it off and looked at the fule mist and it looks good, I have measured the wires from the map sensor to the cdi box and they are ok.
I have 18 K ohm resistor between the spark plug cap and the ground is there anyone who know what it shuld be?
I am grateful for all the help I've missed four races now this sesson I do not want to miss more.

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If you're getting a MAP sensor malfunction, it's not the fuel pump or likely anything else but an issue in the MAP circuit.

- MAP sensor connector not connected or fully seated

- Bad MAP sensor

- Rubber vacuum hose for MAP supply is cracked or not attached

- MAP sensor's plastic tube that rubber hose attaches to is cracked/broken

- Metal tube on TB that MAP supply rubber tube connects to is cracked/broken

- Electrical short or discontinuity (open) in MAP wiring circuit and/or ground: check all connectors for water or corrosion and check grounds for proper metal-to-metal contact

- I believe it is possible to swap the MAP and TPS connectors by mistake, be sure BLUE connector goes to TPS, BLACK to MAP.

Edited by Eddie8v

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The map and tps connectors are not swapt

The rubber hose is ok also the metal and plastic tube is ok

The connecter on map senser is ok i have cleand it and sprayd with contackt oil

I have measured the cabels from map to cdi they are on 1,2 ohm

Anny one who knows how the map sensor works?

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It measures pressure with a simple diaphragm assembly. If you're getting a MAP error code, it has to be one of the things I mentioned. The code means the signal is incorrect, there is no signal, or the signal isn't as expected vs rpm and tps.

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I will try to get another map sensor tomorrow and try with, what i have understood the map sensor is involved in how much fule that the engine is getting, two of the cabels are connected to the tp sensor the other one goes direkt to the cdi box .

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I haven´t got the other map sensor yet but i have become good friend with a mecanik on a bike shop close to my work so I can borrow a map sensor from him and try with

I have messured the resistans in my ignition coil from thr sparkplug cap to ground and there is 18 K ohm is that normal??? I would like to have just around 9 because then the spark will be better.

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I have now tried with a borrowed map sensor and it was a succses no map error and the engine runns good.

When I put back my own still no map error but the engine stops after some seconds and then i can start it again but it has problem

To stay running on low idel, so I will order a new sensor from us for 70 usd because here in Sweden it cost 366 usd,

Anny one who knows how to delet stored fault codes on the ecu with out an expensive instument

Thanks for the help this is a great site

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You don't need to delete any codes. Just ride it if all is well...

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