Hello everyone,
I'm lost, I've read all the threads on the P1688 error code and had my Mechanic try all the recommended diagnostic fixes and the bottom line, it's pouched!
Anyone have any ideas where to source a replacement at at reasonable cost; prices ranging from $4300 CAD to $400 used.
Suggestions please....... Is it worth buying a new one or anyone have a stash of these? 20 year old car and I need to replace all the thread-bare tires so it's getting to that pint. Love driving the car, stored every winter, really want to keep it going.....
Thanks

 

You can try a used one, the OMP itself rarely fails, but the wiring and connectors to it can. If it has been removed from the car, it also needs to be reinstalled in correct alignment. Does your mechanic have experience with rotaries? What are all the things he has tried?
I would never buy a new OMP for $4k, that's worth more than the car. There are plenty of RX8s in junkyards and parts on ebay.
What year is the car?

 

This is a 2006 Red GT. The Mazda dealer shop mechanic had told me that P1688 code meant that because of the oil metering issue caused the Apex seals to go and the engine would need replacing. I asked him him if he had done any compression texts, etc or other tests and he didn't.
Said he'd done all that so I had the car towed home.He obviously didn't want the job, or know what he was doing.

It is hard to find mechanics for an 20 old car let alone one with a Rotary engine. I found a mechanic with 5-star reviews and who had worked on these among several other foreign cars so I took it there.
I had sent him lots of content from this message board including:

I sent him the diagnostic sequence: https://foxed.ca/rx7manual/2003mazda...201600W03.html
2 someones experience on possible water egress in the unit
3 issues with the electrical harness system
4 Possible battery / low voltage problems (seeing that the car went into limp mode shortly after I put it on the road after winter storage. (the battery was at 2.5 volts and need charging. That said, one crank of the key and it started up
5 I also sent him a picture of the various positions of the rotation of the low flow / high flow rotation within the unit.

He had checked my suggestions and said the the unit was pretty much corroded shut. He suggested replacement.
I have found a bunch on eBay and am communicating with him. $550 USD
The new mechanic said he tested everything he could and that was his assessment.

 

Yeah I see, OK. Check GTA rotary club facebook group, there might be someone with a spare OMP.