code 9 on ecu

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intheearlyhours

New Member
ok i got a 91 civic jdm z/c 1.6 DOHC. and i checked my ECu light cause i was having backfiring problems and lose of power and i got 9 blinks from it but no check engine light was on. What do i actually have to replace to fix it. I know 9 is the No 1 cylinder sensor or some shit but the part was like 150 bux and im not even sure if it will fix it
 
check your wiring job from when you installed it. You could have the wires reversed or not properly connected. This sensor is VERY picky on connection. if possible you should run it with shielded wiring.
 
Ok just to be sure. When i check the ECU the first flash doesnt mean anything correct. Cause if it counts than i could be getting code 1 and 8 (TDC) which would make sense with the backfiring. Please Someone let me know what i should do before i waste money on a sensor that may not be broke. CODE 9.
 
if it blinks once, then pauses, then blinks eight times, then pauses, then blinks once, then pauses, then blinks eight times, then pauses, etc., you have a code 1 and a code 8 - try resetting the ECU and starting it up - the code 1 for the O2 sesnsor (if it is connected) won't usually show up when it is first started - at that point, you probably will only have a code 8
 
it only repeats the 9 so i got code 9. I did a reset on the ecu and it came back. I need some info on code 9 so i can maybe see if there is something else wrong besides that expensive sensor
 
Try to be more specific how the 9 flashes were counted. For some silly reason....I am thinking its a different # based on the info you've given about the flashes. One long flash? All short flashes? This info is vital to diagnosing the CEL problem
 
no check engine lite and there 9 short flashes. I really need to figure this out soon cause im starting college soon and i need my car. I checked the cyl sensor with a volt meter and i got power from the sensor (dont member how much) so it is doing something maybe, when i unplug the sensor while the car is running there is no difference in the way my car runs or sounds. When i pull the spark plug from the num 1 cyl the backfiring goes away and it just runs like its on 3 cyl. Please Help me fast. Ill even leave my cell number if needed i need to figure this out ASAP so i can get an education and buy a new civic hahaha.
 
ok i just checked the timing once again and the crankshaft jumped about an inch. WTF. I got a new belt on it and i know i did it right. Hmmm
 
99.9% of the time, a code 9 on the DOHC ZC means that the exhaust camshaft timing is not correct or the wires to the cylinder sensor on the end of the exhaust camshaft are switched - the sensor itself being bad is extremely rare - from your description of backfiring, etc., along with the code 9, i would guess that the timing for both camshafts is not correct

another possibility for the backfiring is that you have some bent valves
 
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it only repeats the 9 so i got code 9. I did a reset on the ecu and it came back. I need some info on code 9 so i can maybe see if there is something else wrong besides that expensive sensor
what ECU do you have? OBD0 D-series ECUs only have short flashes, not long and short, so you just count the number of flashes between pauses
 
im pretty sure its the obdo but ill check later for sure. and yeaha ll short flashes i know i counted right
 
Check the belt.....

Please take out #1 spark plug and gently place a long screw driver into the cylinder. Rotate crank and visual check the screw driver to see when the PISTON is TDC.....this checks piston...not cams. As the screw driver moves...get it at its highest point (TDC) Once you have obtained Piston TDC...then look at the cam gears to see where they are lined up at. This could be the problem and only takes a few moments to check. If that is all good...(like jlicrx said) I would look into wiring connections and, just for shits and giggles, check all the clips to solenoids/sensors on harness to make sure they're all seated in correctly.
 
ok ill do that. and i already checked all the wiring and sensors. im guessing when the screwdriver is at the TDC the cams with line up.
 
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