Professional automotive forum for discussion of the theory of operation for any automotive system or component. Discussions include electrical and electronic theory, engine propulsion theory, fuel system theory, ignition systems theory, and much more. This forum is for experienced automotive repair professionals only, membership required.
Continue to the description of our next automotive discussion forum, the Technical Tips Forum.
| Following Recommended Oil Weights, Best For The Engine? 11/27/2025 in the Technical Theory Forum I saw a very interesting video a friend sent to me. [...] [[...]] In summary, the video claims that in other markets, identical engines/vehicles call for typically 5W-30 rather than 0W-20 for example. A Camry here in the states would recommend 0W-2... | ||
| Leaking Quick Connect At Fuel Rail 11/26/2025 in the Technical Theory Forum I replaced the lower intake manifold gaskets and plenum in July, 2024 due to coolant leaks. That was 120 miles ago and now the 3/8 quick connect to the rail was leaking drip drip drip. The car has less than 40k miles on it and is practically perfect.... | ||
| Low battery warning 11/24/2025 in the Technical Theory Forum [Electrical: 17 BMW i3] The message " battery depleted while the car was off" appears after the car has sat for several days. This is new development. The 12 volt battery is the original. I have not dug into the car but does changing the 12v battery requ... | ||
| Excessive Fuel Trim (Extreme Negative Values) 11/07/2025 in the Technical Theory Forum [Driveability: 16 Chevrolet Malibu LT 2.0L] 2 [2016 Chevrolet Malibu LT, Engine/Propulsion Photo] [2016 Chevrolet Malibu LT, Photo] 2016 Chevrolet Malibu LT 2.0L 8-spd VIN: [...] This vehicle was sent to us by a salvage yard that had sold the installer a... |  |
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