2006 V6 4Runner won't start - Mechanic is stumped

Pale Rider · 2021-11-20T21:48:36+00:00

Please be patient with this long post, but I'm a bit frustrated and want to be as detailed as possible. My '06 4Runner was running fine one day, and the next day it died. First thing I noticed was when I went to unlock the door with the remote key FOB, nothing happened. I had to manually unlock the door with the key. I thought this was odd as it never happened before, so I assumed the battery in the key fob was dead. I then tried to start the car. It cranked over, ran for a second and then stalled. This has never happened before either. Tried starting again and it did the same thing. Tried starting it repeatedly for about 7-10 times. Each time it started, ran for a few seconds and then stalled. After 10 tries it finally stayed running, although rough. After letting it idle for a minute I (stupidly) drove the truck from my house. About 2 miles away I felt it sputter so I immediately turned around and tried to make it back when it completely died on me before getting back home. Called a friend to meet me with jumper cables. With the cables connected, the truck would not even crank over - no clicking, no sounds, nothing at all. Battery is less than two years old. Called AAA and had the truck towed to my local mechanic, who is an excellent mechanic, is very experienced and is an honest guy. After having my 4Runner for nearly four weeks, he has no answers. By process of elimination, he's ruled out the battery, starter, alternator, fuel pump, all fuses and relays and who knows what else. He's sure the problem is electronic in nature, and is leaning towards a bad ECM, though he says he's never seen a Toyota ECM fail in over 20 years of working on and owning Toyotas. He was thinking maybe a rodent got into the engine bay and possibly chewed some wire leading to the ECM. He's unable to tell if it's throwing any codes, because the ECM is not getting power, or something like that. My words, not his. He says he's going to call a guy next week and have him hook up his laptop and try to program the ECM or diagnose it somehow. If this doesn't work, he said my only option is to take it to the dealer, which he does not want me to do, because he knows I'll take a beating from them. But at this point, he is stumped and just as frustrated as I am. I read some previous older threads and was hoping that maybe it was a bad EFI fuse, but I went to the mechanic's today and pulled the EFI fuse from the truck, and it looked fine. Truck only has 135,000 miles on it and, aside from an OME lift kit is basically stock. No engine or performance mods at all. If anyone has any suggestions, I'm glad to hear them. Thanks in advance.