hiroichi1515

iTrader: (17)

I just installed my Crane Hi-6 box today on the leading coil and had a quick question. Can I use the tach output of this cdi box and run it in place of the wire that the trailing coil uses to supply the rpm signal to the tach and ecu. I have my avc-r pulling the rpm signal from pin 1m on the ecu which should be that same wire if im not mistaken. Im guessing that the reading from the cdi would supply the same information or voltage as it is getting now.

The reason why is.... Since I installed my 1st cdi box the trailing coil dies when I use the 2 step function with relays turning off the trailing coil. The coil never comes back on until I restart the car. It instantly pulls up the trailing coil failure in the rtek ecu. I figure if the ecu is still getting a rpm reading it should not shut off and throw the error code. I have tried multiple ways of wiring it up and even down to pulling direct voltage from the battery to the trailing coil via a relay instead of using the main relay since its 20+ years old. Im out of ideas except the one I am asking about.

Thanks in advance.

Sorry for the lack of commas

hiroichi1515

iTrader: (17)

on the ecu I meant pin 1X. Anyway's I tried it and the tach still works but the rpm reading on the ACVR dies and the rtek still gives the trailing coil failure code. I am now thinking of two possibilities. One, the wire I used that goes to the tach stops right there at the tach and there is another wire that takes the signal to the ecu or two, there is something after the tach that intercepts the signal and is also using an additional signal from the coil which it doesn't see when I activated the two step.

hiroichi1515

iTrader: (17)

Well no matter how I wire it the trailing coil still doesn't come back on, so I'm out of ideas to try out. Will sit and wait for opinions until I have another idea...

hiroichi1515

iTrader: (17)

After checking the voltages at pin 1m of the ecu and the tach output from the cdi box I have came up with another idea. The reading at the ecu is almost if not exactly half of the reading pulled from the cdi box. If i can make voltage divider and drop it down I'm thinking it may trick the ecu into believing that it is the actual reading from the trailing coil. I'm not sure how this would work though if there is a different amperage on those lines. So confusing....

hiroichi1515

iTrader: (17)

If anyone wants to know I just wired the tach and the avc-r rpm signal to the tach output of the cdi and called it a day. I don't know how much the trailing coil is needed under boost, but I just decided to do without it for now. That and my brakes decided to go out... What a weekend lol...

hiroichi1515

iTrader: (17)

The final outcome = https://www.rx7club.com/2nd-generation-specific-1986-1992-17/two-step-fun-little-flamage-d-972973/

TonyFc3c

was this ever fixed??

hiroichi1515

iTrader: (17)

Not exactly. Just rewired the tach and ecu to get the signal from the leading coil via the cdi box. Worked perfect but the trailing coils still die once the rev limiter is engaged.