1989 Honda Prelude ECU code light flashing 14

1989 HONDA PRELUDE
180,000 MILES • 4 CYL • FWD • MANUAL
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HENRYHEPBURN
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I was told that the output from O2 sensors should be between 0.1 and 0.9 volts so I just checked them and the voltages are both below nornal range, like 0.042 for one of them. So I decided to take a look at the ECU light with engine off and key on. It's flashing 14. Can you tell me what that means, I tried resetting the ECU by pulling its fuse and the radiuo too. Still the same results. It's a 2.0si FI DOHC Thanks
Apr 13, 2009 at 11:15 PM
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BLUELIGHTNIN6
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Hello Thanks for the donation Below is some information about the trouble code you have along with troubleshooting procedures..


https://www.2carpros.com/forum/automotive_pictures/261618_Noname_454.jpg


https://www.2carpros.com/forum/automotive_pictures/261618_Noname2_123.jpg

Let me know if you need further assistance. Thanks for using 2CarPros.com!
Apr 14, 2009 at 2:27 AM
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HENRYHEPBURN
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Thanks very much, I'll give it try!
Apr 14, 2009 at 8:42 AM
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HENRYHEPBURN
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Maybe I should have mentioned that the Check Engine light never comes on. Perhaps it has a bad bulb? I've only observed the flashing light on ECU. Thanks
Apr 14, 2009 at 8:44 AM
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BLUELIGHTNIN6
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Does the check engine light come on for a few seconds when you first insert key into ignition? This is called the bulb check. If it does not come on then the bulb is most likely blown.
Apr 14, 2009 at 12:02 PM
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HENRYHEPBURN
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Well the check engine light probably is blown out. I'll have to figure out how to get at it next. I did however check the EACV, the resistance was only about 1.5 ohms, not shorted to ground, so I changed it with another unit with a resistance of 13 ohms, now the ECU light flashes code 9 after resetting the ECU. The battery voltage was present at the EACU connector. I noticed yesterday after trying to accelerate rather quickly in a traffic situation that the car seemed to lose power as if it wasn't getting fuel and then it started to surge very intensely and would only hold power when I would try to accelerate. As soon as I tried to just maintain a steady speed it would seem to just drop off or deaccelerate, but it never wanted to stall. After letting the car sit for several hours it seemed OK but I never did try to accelerate quickly again, not wanting to agitate the situation. After that I changed the EACV. Perhaps the ECU has a problem, maybe it's not even the right ECU for this car? I've had this car for about 18 months without having any real trouble with it. Thanks!
Apr 15, 2009 at 7:26 AM
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BLUELIGHTNIN6
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So replacing the EACV did not cure the problem ? Then I suggest substituting a known good ECU.
Apr 15, 2009 at 10:48 AM
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KHLOW2008
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If Code 9 is showing after resetting, you have a faulty distributor which is causing driveability problems.
Apr 20, 2009 at 3:48 PM
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HENRYHEPBURN
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Thanks for that info. I haven't found an exact ECU to swap it with but I did find one from an 89 automatic but the number on the ECU is a bit different. My ECU has A, C-MT 502-221903, and the one I found has 503. I hven't tried it yet but I will soon. I did notice the small wiires in the distributor from the two pickups look a bit shabby like the insulation is disintergrating. Thanks again!
Apr 20, 2009 at 5:30 PM
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HENRYHEPBURN
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I found a broken wire on the plug connecting the "cylinder position sensor" driven by front cam shaft on my 2.0si. The rear cam drives the distributor. I disconnected the battery and reset ECU, no more codes on ECU light. Thanks for all the help! Hope this is helpful to anyone else.
Apr 23, 2009 at 11:06 AM
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BLUELIGHTNIN6
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Great glad you got it fixed and thanks a bunch for letting us know the solution! It will help us help others with similar issues.










Thanks for using 2CarPros.com!
Apr 23, 2009 at 11:31 AM
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HENRYHEPBURN
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Just took the dash apart to check the check engine light bulb, it wasn't there! Voila!
Apr 23, 2009 at 9:54 PM
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KHLOW2008
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Thank you for the input. It is very much appreciated and glad that the problem has been resolved.
Apr 24, 2009 at 10:36 AM