i have a 93 r1 putting new motor from mazda and when i start it, it smokes and when you try to rev it, it backfires out the tail pipe, will go high in rpm if you barely give it gas but if you give it half throttle it sounds like the motor shut off and then backfires, any ideas where to start looking?

 

This same topic comes up pretty often. Your car either has the vacuum hose to the MAP sensor disconnected, is in Limp home mode, or both. Check the line going to the boost sensor, and check the codes. Here's how to check the codes:http://www.scuderiaciriani.com/rx7/engine_codes.html

 

i do not know anything about these cars and i tried to put the motor in because there is knowone around here that will work on them. but the first time i started it ran fine for 30 sec. then the next time i started it was smoking and backfires when you gas it , will not rev up if you give it half throttle but if you give it little gas it does.
when do the secondary injectors come on would them not comming on cause this, would limp home mode do it. how do you know if it is in limp home mode. the check engine light is not on

 

try resetting the ECU

 

how do you reset the ecu i have tried unhooking the battery. i have been trying stuff everyday for two weeks

 

unhook the battery and hold the brake pedal down for about 10 sec's. this should reset it. did you check the codes to see if your in limp mode?
nick

 

the check engine light is not on would i still get the codes

 

Codes can be stored when the light is not on.

 

how would i know if it was in limp home mode?

 

Did you have the injectors clean?

 

no was i supposed to, do you think that is my problem, would it be the secondary or the primary?

 

What color smoke? Black I take it? Do you have a mazda shop manual for the car or did you put everything back together using only what you remembered?


Have you checked the boost sensor(AKA Map sensor)?? If vacum hose going to that is connected then check other vacum hoses that may be disconnected. Check for any nipples on the intake that may not have hoses on them, if you find some then find the hose that's supposed to go on it.