109 k /4.7 liter. 5 codes. my mechanic after much reveiew says new ECM ?? well its. $1000.00 !! after reading much on net . my ques is How do i kno this "culd be" problem. im searching MAF cleaning. but just wonder abt ur toughts on ECM replacement!!?? note these lights sudly came on 1st cold morning september last yr. of which however have randomly gone off/back on again thru out past monts. Neve tho one light at a time. always cluster of the threee. converter(s), 02 sensor, voltage, cyclinder, all chekc out ok also.
thks

 

start off with checking your major battery leads. check the battery terminals for corrosion, fuse box terminals, and major grounds.

 

What codes are you getting?

 

Could be a lot of things, even something as simple as a loose/bad gas cap. Get the codes pulled (most auto stores will loan a scan tool for free) and that will help. I had the same thing happen, replaced the gas cap and no issues since. Have you had any work done to your 4runner recently (particularly suspension work or diagnostics)?