When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
6k ignition break up and tach goes wild simultaneously no matter the engine load
1994 FD RX7. Just replaced my engine, old one was running fine. Now i have a misfire at 6k Rpms and at the same time my tach goes wild. The issue correlates with each other. Wideband also goes RICH when this happens further confirming what i believe is an ignition break up. It does it free reving or under any load. Doesn't matter if its light acceleration of WOT.
Running Power FC master (by FC tweak)
New ignition coil (L1 and L2 pack)
new spark plugs
new wiring harness
new extra grounding kit
gauge cluster already rebuilt
take a look at these videos to see clips. in 2nd video i get some good clips on the end.
https://www.youtube.com/shorts/fwR-Crtv4AM
https://www.youtube.com/shorts/UVMWPXi1LJM
Desperate for help or suggestions! Car runs great besides this issue.
Finally figured it out. I pulled my trigger wheel and it had 2 very slight bends in it! I swapped it out with a spare one i had in my shop that was perfectly straight and everything is good to go now. Hope this helps someone else in the future!
Finally figured it out. I pulled my trigger wheel and it had 2 very slight bends in it! I swapped it out with a spare one i had in my shop that was perfectly straight and everything is good to go now. Hope this helps someone else in the future!
Nice find, and kind of an usual one, you could have been running around in circles forever finding that issue.
Finally figured it out. I pulled my trigger wheel and it had 2 very slight bends in it! I swapped it out with a spare one i had in my shop that was perfectly straight and everything is good to go now. Hope this helps someone else in the future!
Wow, explains why it was localized to the tach too.
I was getting break-up on the dyno at 6000 as well. Shop felt it was the lower engine harness aging out. I replaced the coil harness a year ago and that got rid of some stalling issues.
Just replaced the lower engine harness with brand new from Nengun (C$1000).
There was some delay in delivery, which makes me think they were waiting for a new batch to be made.
Will likely get back on the dyno soon to check things out.
New and 27 year old harness side by side. It was a straight plug in replacement. Seems there is liittle change in the harness across the years and JDM and USDM. My car is a 1999 RHD.
Went for a 1000 km cruise immediately after changing in the harness and the engine was purring like a kitten when cooling down after long runs at high loads.
