Hi,

Recently picked up a non-running FD. Did a compression test and the results were:

Front: 81 - 81 - 78
Rear: 110 - 110 - 111

The test was done cold, with a rotary specific tester. The numbers i reported were the tester's adjusted numbers for altitude, barometric pressure, etc.

Is the difference between the 2 rotors concerning? Can we make assumptions about what may have failed (if anything?) I'd think this would run on one rotor, but it will only start for a second at a time. It fires, then tries to keep idling but dies. I've checked the injectors, and they fire, as well as the plugs were wet when I pulled them. It makes (a lot of) smoke when it fires, so I assume there is spark as well.

 

Change or clean plugs? Sounds flooded to me. I flooded mine once when I swapped injectors. Took a second to foul the plugs.. new plugs and fired up instantly. Someone else should chime in on compression. Seems like quite a difference to me.

 

if the thing isn't running, i would discount the absolute value of those numbers, and instead look at the difference between chambers. in this case its fine. you should be able to get it running, and it will run ok, and then if you retested it, it should get better.

 

Put a new set of plugs in and see if you can get it to crank. Do you have ancient gas in the tank?

Those numbers are good enough for a running, driving, and idling car. The front rotor may just be partially flooded or carboned up, some driving may help that situation out.

Dale

 

I have not tried fresh plugs, as the ones in there look pretty good. I suppose it couldn't hurt. The fuel is fresh, with a little 2 stroke premix oil.

 

Plugs can LOOK good but be fouled. It's not worth chasing your tail when a set of leading plugs is like $6 each at Advanced Auto Parts.

You can just do leading plugs, they do most of the work. Just leave trailing plugs as-is.

Dale

 

This is so true. looking at mine they were damp, but looked great. I figured wth I will try it for the hell of it since it is so cheap, quick, and easy. Immediately started and near perfect idle. I would definitely not spend any more time until you try the plugs.

 

Unfortunately I chased a similar problem after buying my partially running fd for months figuring it couldn't be as simple as new plugs. Turned out to simply be plugs. Bought new leading coils etc. Before just buying new plugs.

I change them pretty routinely every spring now find that it runs infinitely better after changing. Cheap and quick insurance.

 

Of course get it running first to do a proper test.

But If the numbers you posted are accurate both rotors being so far from each other may become an issue.

I had an engine that suffered some "events" on one rotor and ended up with numbers very similar to what you posted. And car seemed to smoke alot, idle rough, was fouling out the plugs on that rotor at idle quickly at stoplights ,and degraded vacuum at idle.
Ended up having a .003" bow on the rx parts apex seals on the bad rotor. Good rotors seals looked perfect still

 

So I threw some new plugs in and it fired right up. For about 8 seconds. I tried a few more times with it running for less and less time on each try. I pulled the plugs out again and they are definitely wet. dabbed them off with a paper towel, and did 2 15 second cranks of the starter with the plugs out, and the egi fuse pulled, throttle wide open, and put the plugs in and tried again. No luck.

However, this is encouraging, since it ran for the initial fire of the new plugs. I'm guessing the apexi ecu is dumping way too much fuel? Any other thoughts? Unfortunately I don't have a fc handheld controller for the ecu. Injector dynamics 1000 / 2000 injectors
Kg parts fuel rail
Apexi ecu

 

If somehow the PFC got reset or lost its program for those injectors you will have issues. You're going to need to get a Datalogit and/or a commander if you want to work with the PFC. Or find someone nearby that can help out with theirs.

Yeah sounds like it's running so rich you are fouling out plugs in short order.

Dale

 

As Dale suggested probably the injector settings are still set for the stock 550cc injectors. If you can find someone with access to the software would be best to start there first, just make sure it would be changed for both primary injectors up to the 1000cc.

Even with the commander it will be a real struggle to get the 1000cc to idle correctly, you really only have the ability to adjust injector duty cycle down to a certain point and most times there needs to be adjustments to other injectors settings not accessible with only the commander once you go up to larger primary injectors.

If you can get it pushed onto a trailer and get it to a tuner familiar with rotaries that would probably be the best option. Sounds like the ECU is currently not tuned to run those injectors your entire map is probably incorrect if it's already having issues idling.

 

Not sure where “yonder” is but if you are near the Atlanta area, I have a laptop with Datalogit on it you can use to get the injectors ratios input correctly.