Yesterday I finally got my FC running after 4 years of sitting at 106$$+ on parts I finally have it running. Well after it warms up and starts and runs for a good 10+ mins after blowing white smoke everywhere and finally stops. I start to drive it and see how it drives. Takes off fine I go to shift into 2nd fine for a few secs and then the car starts to buck hard when you start to give it more gas. When you let off the gas its fine. I couldn't tell you what RPM's it was doing this at because it was 10 at night and the guages either don't work or the light is super dim. Anyone have an idea why its bucking like this? I also have a the CEL on also so I'll try to find out what code its throwing also.

 

Ok well its daylight cranked the car up and see whats going on. Car does that normal jump to 3k rpms for a few secs and then down to 1k. I let the car warm up for about 6 mins and I get in the car. The only lights that are on in the car is the brake ( for obvious reasons), seat belt ( ditto as brakes), and fuel I didn't put a whole bunch in. Ok so I back out of the driveway everything is good so far and I go down the road hit 3k shift into 2nd as I approach 3k rpms the car starts to buck the more gas I try to give it does the same. So I went back into first hit 3k shift to 2nd when I hit 2.5k rpms I shift into 3rd but then it starts to buck a little on also. The CEL comes on, I read on a site well it comes on while driving. It won't be on if I turn the car off and then turn it back on I guess it clears it out but when you drive it will come on and stay on. I hope thats clear kind of zoned out a bit when I was typing this lol.

 

sounds like the clutch. has it been changed?

 

Lol I just ordered one too lol I know the clutch needs to be changed stock clutch that came in the car (I guess). Also it has an erratic idle after its driven it revs up and down. Goes 1.5k moves up quickly to about 1.9 and then goes back down to 1.5 and repeats.

Also my FC is a 91 NA coupe. 5 speed completely bone stock 250k right now I know it has super high miles. The previous and original owner of the car worked for mazda almost all her life and he was religious maintained its whole life at the mazda dealership.

 

Any suggestions?

 

Baaahhhh I don't know it seems like I will be going out and spending all this money of random parts because I can't figure out whats wrong with my FC :[

 

so will the car run above 3k? try just advancing the gas sitting still out of gear and see if it will rev up. id say 5k is ok. this will tell you if the secondary inj are coming online. does it smoke when its bucking? check your pm's

 

Are you running the car on 4-year-old gas? If so, that may be your problem. Drain and fill with clean gas.

 

If you have a CEL light, you can pull the codes. The instructions for doing so are in the 2nd gen FAQ. That will give you at least an idea of what to begin looking for.

Since you mention the car was sitting for 4 years, it could just be a gunked up fuel system. If it was not properly prepared before you started it, trash will have spread through the entire system and caused major damage. See http://www.aaroncake.net/rx-7/unstore.htm for details.

 

I actually used that site and followed everything it said. I didn't bother posting up and saying the problem was fixed. Another member on the forums came by and helped me out. Turns out it was the oil metering pump had shorted out inturn frying a part of the ecu. So the ecu and pump and the tps have all been replaced and the car has been running great!

 

Glad I read this. I've always called that extreme lugging.

 

i have the same problem...except mine kinda sputters when i really hit the gas after 1/2 throttle...my guess is the fuel system too man...mine was sitting for about a year and a half too sooo hopefully it works out for me and you!!!