This problem just started happening a few days ago. I noticed driving around at regular speeds no boosting the car would do a random hesitation/buck. I thought it was a bad tank of gas until I noticed the power fc commander reset real quick and go to the boot up image after every time it does this. I've never had a problem like this before and would like to fix this quickly as I plan on getting tuned in about a month or so. What could cause this problem? Also I filled up my radiator due to replacing a split line and a little bit of water/antifreeze spilled over...could this have caused the problem?

 

Maybe a power or ground wire going bad.

 

I'll have to check this. Any diagram on were to find the power/ground wires?

 

YES, the Mazda FSM and other manuals. You being a FD owner should have already downloaded them to your computer.

http://foxed.ca/foxed/index.php?page=rx7manual

 

Thanks, I had them downloaded on my old computer but it crashed and everything was lost.

 

Ok, so I've been looking through the FSM wire diagram and the ground for the CPU looks like its the one on the engine block by the coils. If this ground isn't fully grounded, would this cause my brief power hiccups in the ecu? Additional information would be I recently put in my new fuel rail and ID2000s, so I was close to that area and may have loosened up the ground. Also when the symptoms happen I notice my air/fuel goes extremely rich (from 11.5 to about 10.0), this seems to only happen now when I'm on the interstate cruising (I can't boost yet due to not being tuned for my larger turbo) it doesn't seem to happen while cruising regularly through the city at 40mph. Just trying to narrow this problem down before I started tearing everything apart again.

 

Check the PFC ground at the PFC as you seemed to have missed that one, why?
Pull the PFC out, and make sure that all pins in the 4 connectors are not loose(pushed out some).

 

Could be one of the relays starting to go too.

thewird

 

Just to update this, the problem turned out to be a loose ground by the coil packs. I tightened that up, checked all the other grounds just to be safe, no more problems...smooth sailing now.