Renault Megane K9K injector voltage walking spike?

Ask for and share advice on using the PicoScope kit to fix vehicles here.
Post Reply
LEYLAND MILL MOTORS
OneWave
OneWave
Posts: 23
Joined: Mon Jul 20, 2015 8:22 am

Renault Megane K9K injector voltage walking spike?

Post by LEYLAND MILL MOTORS »

We have had in today a Renault Megane II 1.5 dCi k9k

The vehicle had a fuel pressure regulator issue which was producing low fuel pump pressure. Delphi pump and false actuators confirmed the fault, regulator changed job done.

While waiting for parts I took the opportunity to get a few reference waveforms.

I was looking at the injector voltage and current on cylinder 1 and noticed a few extra spikes in the voltage trace.
Hooking up voltage to number 2 injector and reference from crank, I noticed a "walking 40 ish volt spike" going between main injection pulses.

Looking at Autodata online, the pizo injectors are connected directly to the ecu separately with no indication of supply or earthing.
I believe the ecu all injectors on each firing stroke with the ecu controlling the earth to operate the injector when required.

I have not noticed this in any others I have checked or tested, this dose not appear to be causing any problems? Yet??
The vehicle runs fine but I am not sure what would give a 40volt spike like this?
Any thoughts or suggestions.
Thanks
Steven
Attachments
Renault_Megane_2007_Diesel_20150914-0003 FILTERED WALKING SPIKES.gif

User avatar
Robski
Advanced User
Advanced User
Posts: 598
Joined: Tue Sep 14, 2010 6:36 pm
Location: Yorkshire

Re: Renault Megane K9K injector voltage walking spike?

Post by Robski »

probably charging the capacitor's.

LEYLAND MILL MOTORS
OneWave
OneWave
Posts: 23
Joined: Mon Jul 20, 2015 8:22 am

Re: Renault Megane K9K injector voltage walking spike?

Post by LEYLAND MILL MOTORS »

Thanks for that
Makes total sense now

Post Reply