hfd59 3 Posted August 18, 2020 I have a 2012 420 that will crank but not start. All in one afternoon it started by stalling at an idle and would restart but hard to eventually a complete no start. Having read that fuel filters and pumps were common this is where I went first. My mistake for not taking the time to collect the correct testing equipment before replacing the fuel pump and filter with Honda parts and still won't start. Has compression, spark, fuel to the injector, fuel spraying from injector when tested out of the machine. Am I looking for a relay or something else that's causing this. Battery is fully charged and has had a tender sitting on it since this started. Any help would be great. Thanks Share this post Link to post Share on other sites
shadetree 5,969 Posted August 18, 2020 welcome to the forums. try spraying a few short burst of starting fluid into the throttle body, if it will not start by doing this ?, then you have other issues going on other than fuel delivery. also, please take a few mins to introduce yourself in the new member section, thanks !. 2 Share this post Link to post Share on other sites
hfd59 3 Posted August 21, 2020 Yes fuel delivery doesn't seem to be the issue and it has spark and compression. Maybe a relay or ECU issue? Share this post Link to post Share on other sites
jeepwm69 7,721 Posted August 21, 2020 Lots of electronic crap on these 420's. The trick that @Melatv taught me to bypass all that crap is to run a jumper wire from battery + to the red wire on the coil. That bypasses the fuel injection relay, the bank angle sensor, etc. If it runs then, you know you have electrical/ sensor issues. If it doesn't, you have fuel or compression issues. 1 Share this post Link to post Share on other sites
hfd59 3 Posted August 26, 2020 Well despite the spark tester showing good spark, visual inspection of the plug grounded to frame sparking replacing the plug has corrected the problem. Thanks for the help 3 Share this post Link to post Share on other sites
_Wilson_™ 6,592 Posted August 26, 2020 good deal... thank you for the update, you did go with a ngk plug ? Share this post Link to post Share on other sites
