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So other than my idle being bad I have another issue dealing with my Map Sensor so I just created another forum to deal with that instead of tagging it on the other post.
My issue with the map sensor is that it isn’t varying voltage depending on the vacuum applied. I had the 5v power and the 12v ground on the middle wire but the control wire that is supposed to vary the voltage isn’t changing at all, staying at around 5v. I know for sure that my map sensor is good (tested on another honda) and have continuity through each wire to the ECU so what else could be the problem?
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OK… Then you do have an issue with the MAP… You have now diagnosed that. If you get a new MAP and do the same test as I instructed, then you should get a fluctuating MAP on Wire #3.
Before I would condemn the ECU, I would definitely trace back the signal wire (Wire #3).
If wire#3 is clean all the way back to the ECU, then you may have replace the ECU… the last thing possible.
It is possible you have both a bad MAP and wire connections/ECU…. it would explain some things.
-Karl
Well I’m going to do the same test on the another Honda to test the map from my Honda. If it test good again I’m going to go crazy. Haha
What do I do if it’s good…….. Idk. Like I said I tested it and it was good on the other Honda and it was good and the one on the other Honda was good too and didn’t work on mine.
I’ll check the wire for consistency/brakes.
Bad wire connection and ECU would defiantly explain a few things… High idle… Running rich… Bad map that’s good…
Having the wiring diagram will be helpful. It is possible that there is another sensor that is sharing the 5V Reference voltage that has shorted out and is causing the problem with the MAP sensor.
Check out this video.
[video width=550 height=309 type=youtube]qymieUlEA9o[/video]
I do have a wiring diagram.
So you’re saying that something sharing the 5v power wire (wire 1) could be shorted? Nothing else is connected to that wire, it goes from the ECU to the Map sensor, the other 2 wires are the same. I didn’t see anything like the diagram in the video in my book so I’ll search for a few on the map sensor and see what else is connected internally.
I have the right reference voltage on wire 1… The first problem is the Map sensor isn’t changing that 5v from wire 1 to a variant of (0-5v) sent through wire 3 to the ECU, depending on the vacuum (map sensor originally tested good on a separate Honda, testing again tomorrow). The secondary problem is I’m getting 5v on wire 3 (control wire) where their should be none. Just want to clarify for anyone else who’s just coming into this forum.
You’ve already determined the MAP sensor works so there is an electrical issue with the vehicle. The video is just an example of what could happen when sensors malfunction and that they could cause problems with other sensors. Your issue may not be exactly the same but all I’m saying is that it’s worth looking into. It is also possible that you may not be able to see physically where the sensors are connected but they may be connected electrically in the ECM where it’s sending out the reference voltage. The only place to find that is the electrical diagram. You could also test each sensor that has a 5V reference voltage to see if they are shorted.
Good luck.
Keep us posted.
Honda MAP sensors rarely have issues. What I do see however is a MAP sensor code being set as a result of an engine performance issue like a misfire or restricted exhaust. I would be looking there for the cause of the MAP code before the MAP sensor itself.
http://www.ericthecarguy.com/faq/solving-automotive-performance-issues
Yes… It isn’t running the way it’s supposed to… One problem at a time… I’m stuck on this one haha. Map sensor isn’t doing what it should ETCG so I’m troubleshooting slowly. Raining right now so I can’t go check things out.
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