I have a 1994 Toyota 4Runner 3.0 V6 4x4 was running perfect then randomly would start shutting off while driving. Now it starts but has a really bad misfire spitting out black smoke, they remove the O2 sensor just so that it can breathe in case it was a cat issue. Also, I changed FUEL PUMP, the distributor, TESTED THE OPEN CIRCUIT RELAY, a Toyota fuel pressure regulator, swaped MFI relay with good ones, check specs on the AFM & TPS, change igniter and ignition coil. Check the resistance on cables, pulled the spark plugs, cleaned them. They look good but didn't replace them. Swap the computer with one from the junkyard and it still has a bad misfire. Finally gave up. Took it to the shop and I feel like they're just playing the guessing game but are telling me that the injector cables have 12 volts but no ground. So when they turned ignition over didn't light up a test light plugged into the cable. There's no pulse going to the injector cable according to them. Would a bad ground on one injector cable cause the rest of them to not get ground since they are in series? Everything I read states that the computer is what grounds the injectors. But my question is is they're supposed to be ground on the injector cable when it's not connected to the injector? My gus says it could be a cable situation since I did change out the butt connectors freeze injectors about 7,000 mi ago. So maybe one is loose or not making a solid connection and I'm wondering if that would impact the other six and cause them to not be grounded. Therefore not sending pulse signal to the injectors. Has anyone experienced this? Again according to the mechanic i have spark but my injectors are not providing the fuel but this I questioned because if this were the case then wouldn't the engine not turn on period?
Any thoughts on what else could be causing the problem? Thank you in advance
Any thoughts on what else could be causing the problem? Thank you in advance
