No acceleration under load
 

Hi,

I'm brand new to rotarys and this community. I didn't expect my first post to be for help but... I just bought a 94 RX7 with about 25k on a facreman. Everything worked great until - I bought a Mazda compression tester on E-Bay and went to test and see if all was ok inside. Disconnected the 8-10 wire connector next to the power steering pump(crank sensor I think) and then the tube to the throttle body - removed both trailing plugs and did the test - everything looked great 85+ across the board . Buttoned everything back up. Started the engine, smooth idle, will accelerate if the pedal is moved slowly but will stumble and not accelerate if the pedal is pushed too far. On the street will not accelerate if the pedal is hardly pushed!!

Checked for things I could have knocked loose. So my questions are: Any suggestions, Good rx mechanic in the Ventura county area, if only one rotor is operating will the engine still be smooth or can you tell when its not firing like a recip?????

Thanks in advance for your help.

Jim Wapelhorst 805 495 3416

85psi is when you have to do a rebuild. It is low. What were the exact numbers?

Hi,

Thanks for the response. All I was looking for was the same magnitude pulse on each combustion chamber. The car was running perfectly until I did the test. I'd like to know how to test the tps as it's right next to the hose I removed to get the tube/plenum off the throttle body.

Jim

Get a manual, even a haynes one. That'll take care of the tps test. In your case, there are too many variables so just eliminate a few with the help of the manual. Yes there is a perceptable difference when only one rotor is firing. The sound is very different and it feels rough.

Gentlemen thanks for your help. The problem has been resolved. The instructions I had for the compression test assumed(!) I knew which connector was the crank position sensor.. Wrong. The picture I had only gave me a general location and as I'm a newbie I disconnected the wrong one- the oil injection stepper motor connector. Then when I cranked for the test I set error codes(50 something) in the ecu and from then on I was in the limp mode. Disconnecting the neg cable for 30 seconds cleared the codes and all is well!!!

While the car was down I put a Blitz cat back rig on and wow a definite noticeable difference.

Thanks again for taking the time to respond it's nice to know there's help out there.

Jim:)