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FJR Motorcycle Forums
Technical & Mechanical Problems
Engine only runs with vacuum line disconnected
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<blockquote data-quote="Zpetrus" data-source="post: 1447536" data-attributes="member: 98038"><p>I did the test on 8-57 of the shop manual for the intake air pressure sensor. The voltage across the blue and black blue lines reads 5.2 with the key on. Spec is 3.75-4.25 I suspect this indicates that the sensor is bad. This was done with lead wires maintaining connections to the bike and testing across them with the ignition on as per the manual. Now the bike is showing a check engine code of 14 instead of 16 which was the earlier fault Both have to do with the pressure sensor. I did not check the one under the seat. A bit of work to get to.</p><p></p><p>Regarding the TPS I ran the diagnostic and it is within spec and working smoothly. Unless you think it is possible that the Diagnostic is wrong and reading something different than the ECU.</p><p></p><p>Interestingly, if I unplug the intake air pressure sensor the bike will not start at all - vacuum line connected or disconnected. </p><p></p><p>I am going to do the disassembly required to get to the APS today perhaps if it is disconnected it will solve the issue since it is way off and the default is closer to what exists here.</p><p></p><p>Again, Thanks for the pointers Torch</p></blockquote><p></p>
[QUOTE="Zpetrus, post: 1447536, member: 98038"] I did the test on 8-57 of the shop manual for the intake air pressure sensor. The voltage across the blue and black blue lines reads 5.2 with the key on. Spec is 3.75-4.25 I suspect this indicates that the sensor is bad. This was done with lead wires maintaining connections to the bike and testing across them with the ignition on as per the manual. Now the bike is showing a check engine code of 14 instead of 16 which was the earlier fault Both have to do with the pressure sensor. I did not check the one under the seat. A bit of work to get to. Regarding the TPS I ran the diagnostic and it is within spec and working smoothly. Unless you think it is possible that the Diagnostic is wrong and reading something different than the ECU. Interestingly, if I unplug the intake air pressure sensor the bike will not start at all - vacuum line connected or disconnected. I am going to do the disassembly required to get to the APS today perhaps if it is disconnected it will solve the issue since it is way off and the default is closer to what exists here. Again, Thanks for the pointers Torch [/QUOTE]
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FJR Motorcycle Forums
Technical & Mechanical Problems
Engine only runs with vacuum line disconnected
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