× Auto Repair Pros Member Benefits TechHelp Knowledge Base Forums Resources My iATN Marketplace Chat Pricing About Us Join Industry Sponsors Video Members Only Repair Shops Auto Pro Careers Auto Pro Reviews
Join Now
International Automotive Technicians Network

Automotive Technical Theory Forum

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.

Recent Automotive Discussions in the Automotive Technical Theory Forum

Lower voltage at higher rpm?
08/15/2018 in the Technical Theory Forum
[Electrical: 03 Dodge Dakota 4.7L] This is my own personal vehicle, 2003 Dakota 4.7l. After driving for at least 10 minutes, if I hold the rpm above 4500 for more than 3 seconds, the volt meter will drop, and the battery light will come on, then stay on ...
08 Audi 4.2 P0341, P0301, P0303
08/13/2018 in the Technical Theory Forum
[Driveability: 08 Audi S4 Avant 4.2L] I heard an engine knocking noise on the cold start. The engine runs rough and there is very little power brake assist. The brake vacuum booster is connected to the intake. I was called in to diagnose the cmp and misf...
07 Ford Edge 3.5 P0353, P0355
08/07/2018 in the Technical Theory Forum
[Driveability: 07 Ford Edge SE 3.5L] The shop replaced all COP coils and plugs with OE, but the codes and misfires are still there. One of the COPs that was replaced was cracked. The firing order is 1 4 2 5 3 6 and cylinders 1 2 3 are near the firewall, ...
GM 3100 oil? In coolant. Dexcool sludge
08/07/2018 in the Technical Theory Forum
[Engine: 02 Buick Century Limited 3.1L] I am looking for some feedback from techs with more experience on the GM 3100 engines than I have. This last week I have seen 2 cars with brown sludge in the coolant overflow bottles. Beings the coolant systems had...
DC relays .Purpose of the diode
08/04/2018 in the Technical Theory Forum
Some here have posted that (if I remember right) that the purpose of the diode was to make the magnetic field collapse faster. So what's your thoughts on this theory ?

Automotive Sponsored Discussion Forums