Mazda Rx7 started misfiring after rebuild
#1
Junior Member
Thread Starter
Join Date: Mar 2017
Location: BC, Canada
Posts: 15
Likes: 0
Received 0 Likes
on
0 Posts
Mazda Rx7 started misfiring after rebuild
Hi, guys, I need some help with my 13b REW 1992 JM1FD, I have rebuilt the motor after rebuilding it's not running okay, it does idle very smooth around 950 to 1000 rpm. when I give it a sudden gas. it does very bad misfiring and doesn't want to Rev up. I did disconnect the trailing spark plug wires in order test the misfire on Leading plug, So it's doing the same. Plus it's running pretty Rich, I have noticed O2 sensor wires were not connected. what could be issue Bad Map sensor?
Engine running
https://www.instagram.com/p/BRLtIatAUEw/
Engine running
https://www.instagram.com/p/BRLtIatAUEw/
Last edited by fraz ali (Khan); 03-13-17 at 08:54 AM. Reason: Video. Of engine running
#3
Junior Member
Thread Starter
Join Date: Mar 2017
Location: BC, Canada
Posts: 15
Likes: 0
Received 0 Likes
on
0 Posts
Thanks for reply Chrisaleggett, are you sure that a check valve? I thought that black check valve shape thing is just a filter, not an actual check valve, it does bypass air on both ends. And yes right now the Arrow of this filter pointing towards map sensor, not to engine side.
#6
Junior Member
Thread Starter
Join Date: Mar 2017
Location: BC, Canada
Posts: 15
Likes: 0
Received 0 Likes
on
0 Posts
Here is the link of engine idling
https://www.instagram.com/p/BRLtIatAUEw/
Yes cas are hooked Okay otherwise it won't start
Any more suggestion, if I Rev slowly it revs higher than again start misfiring with very loud blast, problem seems like ignition timing. What you say
https://www.instagram.com/p/BRLtIatAUEw/
Yes cas are hooked Okay otherwise it won't start
Any more suggestion, if I Rev slowly it revs higher than again start misfiring with very loud blast, problem seems like ignition timing. What you say
#7
Junior Member
Thread Starter
Join Date: Mar 2017
Location: BC, Canada
Posts: 15
Likes: 0
Received 0 Likes
on
0 Posts
Trending Topics
#9
Thanks for reply Chrisaleggett, are you sure that a check valve? I thought that black check valve shape thing is just a filter, not an actual check valve, it does bypass air on both ends. And yes right now the Arrow of this filter pointing towards map sensor, not to engine side.
Flip the valve around and stop running fat. Also be careful not to break the plastic nipple. Good luck let us know
#11
#13
Junior Member
Thread Starter
Join Date: Mar 2017
Location: BC, Canada
Posts: 15
Likes: 0
Received 0 Likes
on
0 Posts
did compression test on cold and weak battery it was 75 psi. before rebuild it was 65
Hi rotary evolution thanks for your time, I did test the compression on both rotors it was 75 psi on cold engine with pretty weak battery, before rebuild it was 65 psi on hotter engine and it was running pretty fine bro. Only reason for rebuild was blown water seal. I will test the compression for you again and make video. Have you watched my video, in which car is running?
here is the link:
here is the link:
#14
Junior Member
Thread Starter
Join Date: Mar 2017
Location: BC, Canada
Posts: 15
Likes: 0
Received 0 Likes
on
0 Posts
I did test the compression on hotter engine , its giving 90 to 95 psi on both rotors, So Compression is okay. other important information. engine is burning alot of fuel, when ihave removed the plugs, there pretty black. So any more suggestion here?
#16
Junior Member
Thread Starter
Join Date: Mar 2017
Location: BC, Canada
Posts: 15
Likes: 0
Received 0 Likes
on
0 Posts
overall was 90 to 95 on both rotor, i did test each 3 pulse with hand tested method which are pretty strong and all 3 pulse on both rotor seems equal pressure. bro, earlier this engine was on 65 psi on both rotor and it was starting very late, but when it started once, it revs proper with some normal misfiring, ... right now with new engine after 2000 RMP it starts misfire with huge loud blast, for example a piston engine would do that on wrong ignition timing.