Search found 162 matches

by picowight
Mon Mar 11, 2024 8:34 am
Forum: Diagnostic discussion
Topic: PWM Actuators.
Replies: 5
Views: 301

Re: PWM Actuators.

I have done this a few times to spot a sticking fuel inlet metering valve. This was a 2.0L diesel that would fault intermittently - say once an hour of driving. I could see the fault in the pressure regulator even though it did not actually fault at the time - I had pages of normal operation like th...
by picowight
Fri Dec 29, 2023 5:24 pm
Forum: PicoScope 7 Automotive software
Topic: Lost all my stored Math Channels Pico 7
Replies: 2
Views: 6875

Re: Lost all my stored Math Channels Pico 7

Try loading up a saved waveform that used one or more of the channels they should come in with it.
I had a similar issue with stored custom probes.
by picowight
Sat Dec 16, 2023 10:51 am
Forum: PicoScope 7 Automotive software
Topic: Cylinder Timing Overlay
Replies: 5
Views: 5361

Re: Cylinder Timing Overlay

Would be so cool to have this (or something similar) built into PS 7 maybe Steven McGrew would be amicable to it's use?
Otherwise it is useable but a bit clunky, plus it needs Windows!
by picowight
Wed Dec 06, 2023 9:29 pm
Forum: Automotive kit hardware
Topic: PQ334 vs WPS500
Replies: 4
Views: 11890

Re: PQ334 vs WPS500

Can you explain the high price of the PQ334 ?

Whilst there is a "proprietary premium" of the BNC+, even when compared with other BNC+ units -such as the 30A clamp at £177+VAT for example, to me £300+VAT is difficult to justify the benefit over a very similar performing but non BNC + unit for £80.
by picowight
Thu Nov 30, 2023 10:44 pm
Forum: Diagnostic discussion
Topic: Stuck Quantity Control Valve
Replies: 2
Views: 2235

Re: Stuck Quantity Control Valve

I often use the current waveform of rail pressure regulating valves, solenoids, position motors etc - pretty much anything you would expect to move smoothly, to detect if it is sticking from a current anomaly. In the case of EGR and VNT the ECU will often cycle them stop to stop at ign on/off. Even ...
by picowight
Thu Nov 30, 2023 9:58 pm
Forum: Diagnostic discussion
Topic: Missing data between frames, Setup issue?
Replies: 3
Views: 3654

Re: Missing data between frames, Setup issue?

The way to do this is to set a trigger for one of the channels that it will never reach - for example set the Cam sensor at 16v and set it all the way at the end (right hand side) of the screen, then set the trigger to repeat or anything except auto. Run the scope on say 2s/div and when the data rea...
by picowight
Sat Nov 18, 2023 7:54 pm
Forum: Diagnostic discussion
Topic: Toyota Auris 1,4 d
Replies: 12
Views: 14373

Re: Toyota Auris 1,4 d

No Sign of OP but I would bet pump destruction put little bits of pump all through the fuel system - either bad pump or miss-fuel. That would kill all 4 injectors. Take a sample from the return line and look in a black cap with a strong light for glitter or cloudiness. 1.4V /300 bar is too high on c...
by picowight
Tue Nov 14, 2023 2:08 pm
Forum: Diagnostic discussion
Topic: BMW N3 - GDI/NA misfire when cold
Replies: 5
Views: 2642

Re: BMW N3 - GDI/NA misfire when cold

I think Cyl 2's intake valve is leaking on the power stroke spiking the intake with exhaust gas, right at the time Cyl 3 opens it's intake valve. See the overlay pic above. When Cyl 3 misfires it has spark, fuel and compression and all at the right time. That leaves a) measuring error or b) bad air....
by picowight
Mon Nov 13, 2023 7:03 pm
Forum: Diagnostic discussion
Topic: BMW N3 - GDI/NA misfire when cold
Replies: 5
Views: 2642

Re: BMW N3 - GDI/NA misfire when cold

Thanks, I like the plan for a one shot, think I'll use that next time I come to the it's mechanical conclusion. I focused on the faulty cylinder(s), eliminated bad new/old parts, eliminated ECU control, and then went in for in-cylinder, though I did do an RC first (all even). I actually now have an ...
by picowight
Sat Nov 11, 2023 3:25 pm
Forum: Diagnostic discussion
Topic: BMW N3 - GDI/NA misfire when cold
Replies: 5
Views: 2642

BMW N3 - GDI/NA misfire when cold

This is a really interesting one, N53 Engine, misfires on 3+5 when cold, sometimes 1 as well. When it misfires all the ECU signals are there, spark primary on 2(good) vs 3 (bad) are normal and identical, current signature of (piezo) injectors is same on both. Cam/Crank timing is good. Borescope in t...