Ford Zetec Rocam Blunder - BSFEEChannel #14 - Page 1
Forum section: electronics / general

author: bsfeechannel
author_rank: Super Contributor
timestamp: February 24, 2018, 09:07:16 pm
content: Or how engineering is like walking on a razor edge.

author: AllTheGearNoIdea
author_rank: Unknown
timestamp: February 28, 2018, 08:45:28 pm
content: Had a look at your channel and you have some interesting stuff on the automotive electrical side of electronics. The robot voice thing just sounds horrible and most people wont even try to watch your channel. Drop the voice and you will do fine.Thanks for sharing

author: bsfeechannel
author_rank: Super Contributor
timestamp: March 01, 2018, 05:35:14 am
content: Thanks for watching. The approach on cars is purely incidental. Below I provide the script I fed to the computer. So you can turn the volume off and watch the video again.Quote

author: AllTheGearNoIdea
author_rank: Unknown
timestamp: March 01, 2018, 08:03:18 am
content: Im just suggesting that you use your own voice because absolutely no one likes to listen to the robot voice woman it sounds just awful. Unless of course your some kind of mafia guy on a witness projection program in which case I’m saying nothing and anything you do is fine with me.

author: GeorgeOfTheJungle
author_rank: Super Contributor
timestamp: March 01, 2018, 08:28:42 am
content: Interesting stuff indeed!IIRC some Hondas had a similar issue in the '90s, they issued a recall to replace the HV/ignition/spark plug coils.

author: bsfeechannel
author_rank: Super Contributor
timestamp: March 01, 2018, 03:54:35 pm
content: Quote from: AllTheGearNoIdea on March 01, 2018, 08:03:18 amMore of a fan of Kraftwerk and Daft Punk.

author: AllTheGearNoIdea
author_rank: Unknown
timestamp: March 02, 2018, 08:14:10 am
content: Kraftwerk whats not to love.

author: mikerj
author_rank: Super Contributor
timestamp: April 24, 2018, 03:58:14 pm
content: Note that all throttled spark engines have a variable spark voltage, but it's the pressure in the cylinder that determines this voltage, not the ECU.When the ECU decides it's time for a spark it cuts off current to the coil primary (for an inductive ignition system), and the voltage on the secondary of the coil naturally rises until the gas between the spark plug electrodes is ionised. The voltage required to achieve ionisation is roughly proportional to the pressure in the cylinder (Paschen's Law), and this pressure increases with engine load, i.e. when you open the throttle, more air is allowed into the cylinder and the coil voltage has to rise higher for the spark to form.

author: bsfeechannel
author_rank: Super Contributor
timestamp: April 24, 2018, 08:15:14 pm
content: Quote from: mikerj on April 24, 2018, 03:58:14 pmI thought that because this is a naturally aspirated engine with fixed compression ratio, the absolute cylinder pressure (for a given constant atmospheric pressure) would be the same regardless of load and speed. But obviously I was wrong.This made me conclude that the ECU's control over the amount of energy that the coil stores accounted for the variable spark peak voltage. In any case, it is good to know that this is a problem that can happen with any engine of this kind if not enough attention to detail is given in the design.Thanks for the input.