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Discussion Starter #1
please read everything.

Code 56. VTC solenoid mailfunction. It represents my last hurdle.

Im going to paint a picture, and however kindergarten it may seemed when typed out, i assure you its just to paint a full and accurate picture so that someone can actually diagnose it over the internet.

car runs like complete shit/misfires UNTIL it throws code 56, at which point it runs great (albeit pig rich) MINUS VTC and VTEC. (strange to me)

i have checked the part numbers on the 2 cam triggers, and they are all the same, vtec/nonvtec k20/k24, so i have the right ones in there by default.

the solenoid on the other side of the head is a "PNB".

what i have done thus far:

1. cross referenced part numbers to make sure i have the right solenoid (i do, as the new honda part number for it is PNB)
2. ordered a new solenoid from honda. 9765 japanese yen.
3. pulled the VC and checked timing. crank pulley, cam gears, pulse plates, straight as an arrow.

what i have not done as of this second, but will do after work today.

1. check the wiring of the solenoid sensor pin to pin (ecu to sensor) i have a 05-06 harness, a ep3 ecu and a 02-04 conversion harness. i repinned the 05 harness completely, but i might have missed something, however i doubt it.

to me, the most obvious answer is that the timing is off a tooth, however i dont think it is. i checked. im going ot check it again, but it was straight.

has anyone had this situation rear its head?
 

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IMAKEBOOSTATIDLE
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my buddy to this day has this same code.. let us know what you find out. he is about to give up and sell his RSX he has a built k20a2 with BC stage 2 cams.
 

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check your tensioner.

I believe this is the code blake had when he had all his issues, we thought it was a busted solenoid too, or even gear, changed both, still a problem, checked timing, fine. Pulled the motor, tensioner was done.

I cant remember the code blake had. i'll try to find out.
 

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ok, just threw it out there, blake's had similar issues to yours, his kept running, blew smoke, had a code, no vtec, timing and all was on/set.

hm. i'll think about this
 

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Discussion Starter #6
i just solved it.

you guys ready for this?

timing chain tensioner has oil passage.

VTC check checks pressure within the entire VTC system.

i over torqued the timing chain tensioner, so oil will not pass through it. torque is only 9 or so ft/lbs and i probably put that fucker on there with 30ft lbs so oil wont pas properly through it, thus not allowing the system to work when it runs its VTC check.


now, who wants to bet me a unicorn it works if i retorque the thing?

hell im about to tell my boss i have diarhea so i can go home and do it.
 

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i just solved it.

you guys ready for this?

timing chain tensioner has oil passage.

VTC check checks pressure within the entire VTC system.

i over torqued the timing chain tensioner, so oil will not pass through it. torque is only 9 or so ft/lbs and i probably put that fucker on there with 30ft lbs so oil wont pas properly through it, thus not allowing the system to work when it runs its VTC check.


now, who wants to bet me a unicorn it works if i retorque the thing?

hell im about to tell my boss i have diarhea so i can go home and do it.
I will see you that Unicorn, and raise you a Pegasus.
What did you tighten it with? An Impact?
 

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acura? thats that "A" emblem all the kids put on their Honda Sabers, huh

aaron read my last diagnostic post. im a golden god and idiot.
You should start hyping Donks with the locals. I will ship ya wheels and Oldsmobiles and Impalas and shit, you ship me some R33s and Aristos. Hell, I will even ship ya some NSXs and AE86s, but we split the profit on those :silly:
 

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Discussion Starter #13
I will see you that Unicorn, and raise you a Pegasus.
What did you tighten it with? An Impact?
i am stronger than a 1/2 in drive impact.

i just cant gyrate my arm that fast.

but i used a t handle. im going to do that after work, then ohm out the solenoid itself.

hey import racer, ask your friend if he has ever changed his tensioner. also tell your friend that in the factory service manual there is a test for the VTC system. 2 of them. one if ohming out the solenoid, and the other i have to finish reading.
 

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Discussion Starter #14
i pulled this from 8th civic. something to consider.

"I finally figured it out. After replacing the VTC solenoid, running an entire new signal wire form the ECU to the solenoid, replacing the oil filter, and cleaning the VTC strainer. It ended up being that the ECU pin C27 in the green coneector was too loose. It had too much play side to side. The way I fixed it si a little crude but I removed one of the yellow plastic pins that are used to close up the unused terminals in the connectors and jammed it into the terminal to keep the pin from moving. This worked and my VTC is now operational.

Now if anyones VTC ever fails your car will run like absolute crap. The intake cam stays at zero degree advance and will not allow enough air in for normal operation. It also disables vtec completely. Your fuel mileage will drop about 10mpg and you will probably lose about 30whp. I hope this helps someone in the future. "
 

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Sorry to hear the "Togue Terror" has hit a pebble in the road. I think you are missing a cog or two.
 

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I highly, extremely doubt the over tightening of the TCT idea.

The TCT sources it's oil prior to the VTC system and is not impacted by any VTC test or check.
 

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Discussion Starter #19
problem solved.

just to follow up, my harness needed to be re-pinned a few weeks ago. i highlighted one pin on the B plug on my diagram so i would not "forget" to pin it. it was the "VTC negative" or "ground" as the ECU grounds the system.

i had to essentially run a new wire for it because after peeling half my harness apart i could not find the right black wire. but its re-integrated into the harness and runs to the proper plug which is B20-something (refer to the diagram in chapter 11 of the FSM)

so, to bring the VTC issue full circle, this is how i would trouble shoot it, starting from dumbest, to most difficult

1. clean VTC screens. 2 on solenoid, one on head behing autotensioner. change oil/filter
2. ohm out solenoid at ECU. 7-10ohms between VTC positive and VTC negative on B plug ECU
3. ohm out the solenoid itself from pin to pin (its a 2 pin solenoid, pos and neg)
4. check wiring continuity, especially if you have a swapped car with a conglomeration of harnesses like i do.
3. oh
 
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