On 01/10/2026 8:11 PM EST Finn Lassen finn.lassen@verizon.net <flyrotary@lancaironline.net> wrote:

 

 

 

Sorry for the multiple posts. Not quite with it today.

 

Here's another idea. We now know the injectors are working -- but all four?

If only secondary injectors work then engine will die.

Not sure how easy it is for you to get to injector connections, but you try to disconnect all but one at a time (in test mode) to make sure each of the four actually work.

 

Finn

 

On 1/10/2026 12:07 PM, Doug Lomheim rv9flyer13b@gmail.com wrote:

Finn:  Thanks so much for these additional steps to try!  

 

Looks like we can rule out “0, 3, 4” (?) since the injectors click away and the leading and trailing plugs fire up nicely?

 

Can’t we also rule out “1” (Injector drivers) since the injectors operated nicely in Mode 0 when “priming”?  

 

Also, does this rule out a possible CAS issue…maybe the CAS circuit  is somehow used in firing the plugs at “3,000 rpm” in mode 8?

 

Doug 

 

 

Would be interesting to know which part of the A controller failed. 0) 5V power regulator 1) Injector drivers 2) Ignition coil drivers 3) Crank angle sensor input. 4)  MCU itself. Do the injectors click when you press the Store button or when you put it into injector test mode? Do the spark plugs fire when you put it into test mode? If either of those work we can rule out 0, 3 and 4. As for compatibility, the main difference between 13B and Renesis is the crank angle sensor output. The 13B has magnetic pickups and the Renesis has a timing wheel, so you can't switch them without reprogramming. Then there is dwell time -- depends on iginition coils you use. I suspect that other differences can be handled by tuning. Finn

 

 

On Jan 9, 2026, at 4:59 PM, DOUGLAS LOMHEIM <dlomheim@aol.com> wrote:

My Renesis “A” processor went INOP a few weeks ago, and I’ve done the following:  a). Verified 12 V to BOTH EC2 power pins.  b).  Verified continuity from OAT two wire thermistor to EC2.  c).  Replaced thermister with the one on my 9A project.  d).  Opened the EC2 to ensure the micro processor was still seated in its’ socket.  
The “A” side is still not functioning, and must be started on the “B” side, and when switched to “A”, it immediately dies.   

Are there any other trouble-shooting steps I should try?

Thx.  Doug

P.S.  I believe Tracy did some special EC2 processing on  Renesis EC 2s, vs RX-7 13B?  I think I have two extra EC2s, so could swap them out IF they are compatible with each other…

Thx for your inputs, Doug
Sent from my iPhone