Hey Guys

New to the RX7 club needed some rotary info and even though its not in a car its still the same motor well kind of. I bought a 93-95 13B-REW from JDM in North Texas to put in a jet boat I built. I was looking for a light weight , high revving, reliable engine for this project and I settled on a 13B. I got the engine to my shop and went to work on it. I wanted to get rid of the turbos and everything vacum related, and everything else not needed in a boat. Got the engine painted and put back together and hung a 371 Detroit diesel blower on the side of it. Couples it to the jet pump and put it in the water. Here’s the problem, Under a No Load situation, on a trailer out of the water, the engine runs perfectly. Idles 700 rpm with no galloping and start advancing throttle and the motor takes off and runs perfectly with no hesitation or problems. The problems starts when the engine is put under a load. When the boat is in the water, jet pumping water, It starts perfectly idles the same as no load 700 no galloping, start to advance the throttle runs great to about +-2000 rpm then it just falls on its face. Will not throttle up and just runs like crap, throttle below 2000, and runs great again. I need help, I don't know what’s wrong. Any input would be greatly appreciated, Thanks.

I will also post this on Tech Support in the main forum.

 

What computer are you running.?

 

Stock

 

Pull codes. Limp mode? Do you have a check engine light on?

 

Limp mode will hinder ignition advance and fuel under load. you need to look for codes 26 and 27 OMP. Is your omp connected properly? Code 45 Charge circuit, also a few more. I am not up to speed on the 3rd gen.

 

that is a awesome idea.

 

I did not use any of the Dash Lights on the project, and I striped all wiring off the engine that was not essential to make it run. Is Limp Mode only activated when the engine is under load? No load situations the engine runs perfectly. How else can I tell if the ecu is throwing a limp code? Thanks

 

 

Heres another:

 

Yes if you stripped the omp wiring for instance the motor will not run under any load. You will nerd to pull codes. On the s5 its easy. Unfortunately I am not sure on s6, but you should be able to search for pulling codes on s6. You may need a test light.

 

I did not remove the oil metering pump, and the harness is connected correctly. I know this because I unplugged the omp and ran the engine under no load and it did the same thing, broke down after 2000 ish. I checked the vacuums going to the oil injectors, they are the only vacuums i have other than one to fuel pressure reg. Could it be that the secondary injectors are not coming on line at 2000, and the engine cant produce enough power to get them to come on line at 3800 or so? I don't know rotarys that well but could it be a fuel issue?

 

You need to pull codes first as other issues will cause limp mode. That way your not going in circles. Should be easy enough. Mass air flow and tps I believe may cause limp mode. http://www.banzai-racing.com/FD&S5_error_codes.htm

 

You will need a check engine light to perform the function. I do not know which ecu pin you use for that. You need user "satch" to help on that