bayside_supra Posted October 14, 2018 Share Posted October 14, 2018 Hi everyone I have had a misfire at high boost for about 6 months. Car runs fine off boost and perfect at 1.5 bar. Turn it up to 1.7 bar and it misfires on full throttle from about 5k upwards. So far i have replaced spark plugs, coil packs, and the whole coil pack loom, all with brand new parts. No real change apart from it was misfiring at 1.5 bar as well before the coil packs were replaced. It started shortly after I had my engine dressed but I think we have addressed everything that could have caused it from that now. The only thing we haven’t touched is the adjustable cam gears I had fitted fitted at the same time. Darren @ magnum performance says this is unlikely to be the culprit and they were only for looks anyway so no adjustments to timing have been made. Any ideas? Link to comment Share on other sites More sharing options...
Mike2JZ Posted October 14, 2018 Share Posted October 14, 2018 What plugs are you running, and what have you gaped them too? Any idea on what your air fuel ratio is whilst boosting at 1.7 bar? Any idea what fuel pressure you are running during boost? Link to comment Share on other sites More sharing options...
bayside_supra Posted October 14, 2018 Author Share Posted October 14, 2018 What plugs are you running, and what have you gaped them too? Any idea on what your air fuel ratio is whilst boosting at 1.7 bar? Any idea what fuel pressure you are running during boost? Ngk iridium 8s. Not sure on air fuel ratio and I have no sensor, but I can have a look at the toucan next run to see the fuel pressure. I need to do a Syvecs log to send to Romain, just haven’t had a chance yet. Link to comment Share on other sites More sharing options...
bayside_supra Posted October 14, 2018 Author Share Posted October 14, 2018 Car is single turbo just over 700 fwhp btw Link to comment Share on other sites More sharing options...
mellonman Posted October 14, 2018 Share Posted October 14, 2018 how are your injectors haves just finished chasing down a sort of similar issue Link to comment Share on other sites More sharing options...
and1c Posted October 14, 2018 Share Posted October 14, 2018 Have you replaced the ignitor? Were the coil oacks new oem ones? Link to comment Share on other sites More sharing options...
bayside_supra Posted October 17, 2018 Author Share Posted October 17, 2018 The new coil packs were uprated Whifbitz ones. Injectors should all be fine too, admit 850cc. How would you check injectors? Ignitor was checked but not replaced Link to comment Share on other sites More sharing options...
Chris Bailey Posted October 17, 2018 Share Posted October 17, 2018 We had a similar issue a few years back, would missfire on 1.8bar at 5krpm. Turns out the Whifbitz coil packs we had that were fairly new wasn’t up to the job. I’d advice always replacing coil packs with new OEM ones. Link to comment Share on other sites More sharing options...
scott.wild Posted October 17, 2018 Share Posted October 17, 2018 What plug gap are you running, I had a similar issue, closing the gap very slightly sorted it Link to comment Share on other sites More sharing options...
mellonman Posted October 17, 2018 Share Posted October 17, 2018 after market coils are so much weaker then stock it you can clearly see even with 10 yeah out stock ones out performing 1 year old super sparks Link to comment Share on other sites More sharing options...
bayside_supra Posted October 23, 2018 Author Share Posted October 23, 2018 Only just recently driven the car again to try and get to the bottom of this. Replacing the old oem coil packs with Whifbitz ones didn’t seem to make any difference. But they are advertised as being stronger and producing a higher spark. Are we saying they don’t? I have now sent the logs off to Romain, I will get him to check the fuel pressure. Link to comment Share on other sites More sharing options...
Samurai 20V Posted October 27, 2018 Share Posted October 27, 2018 Can confirm that Super sparks are definitely not to par of OEM. After 4 years of running them at BPU, they have hairline cracks and causing a misfire. Fitted the original OEMS from my car, which are 20 years old, they have worse cracks than the Super sparks, mis fire gone.. Link to comment Share on other sites More sharing options...
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