I bought this truck 2 years ago and after the first fillup of regular gas "87 octane" it started pinging pretty badly so I had to use min. 91 octane to stop pinging under load. After looking down the spark plug hole I noticed alot of black stuff on top of the pistons and figured i was getting pre-ignition from all the carbon buildup. So I recently rebuilt the head and all the valves were in rough shape and some were not seating properly after my leak down test There was alot of carbon buildup, i replaced all valves , crank,cam and knock sensor was replaced, all gaskets yatta yatta. There is no instructions on how to use the crank alignment tool so I just positioned it between two teeth on the pulley, looked at the old sensor where the bolts made their mark and I beleive it is setup the exact way the old one was. It flashed up just fine with no codes, took for a road test and put regular gas in it and it was pinging even worse. I cleaned the maf sensor and no changes. I have good compression and good fuel pressure. Double platimum plugs and wires are near new. I took off the pcm and noticed some corrosion on the pins so cleaned those thoroughly with alcohol and no changes. I'm going to get a diagnostic test soon but the only issue I can think of is maybe I did not use the crank sensor alignment tool properly and the timing is too advanced. There is a gap of teeth on the crank pulley, am I supposed to use that as a setup reference? I can't find any info anywhere on how to setup? This truck has been driven about 1000 miles since the work has been done so pretty sure the pcm has re-learned after being reset. Any help would be greatly appreciated! I drive 4000 km's a month so I don't want to kill this engine from ingition issues..
ignition problems on 2002 Mazda B2300
by ripituper in Seattle, WA on March 05, 2011
ANSWER by Superbob , March 05, 2011
I'd say check the function of the EGR system and check the knock sensor. if the EGR is not working right, then the pinging may not be an ignition timing issue. If the knock sensor is not wirling, then the computer is not getting all it's needed inputs to set ign timking. I've heard of pinging problems with the 2300 engine and heard reports of replacing the MAF getting some improvement. Also, I've gotten reports of carbon buildup like you mentioned. if you want to find a specialist, here's a directory link for you: https://repairpal.com/directory?address=98101&car_brand_names=Mazda