What are these HV ignitionwaveform are telling me

Still battle every day with this 3VZ-E engine that refuses to run smooth and reliable.

Please take a look at the attached Scope pic with my Pico 2205A and please give me a clue as to that is going on.
It does not seem to have any intake manifold leaks, I smoked it.
New Ignit.cables, coil, igniter, distributor, TPS, starter (Old one quit)
Knock sensor new but attached to the engine lift plate.
With the paper clip on or of on the engine connector there is no difference
Runs and starts better when cold, after a long warm-up it quits slowly on rpm until it dies. when hot and does not start, propane injection does not help.
Exaust does not seem unreasonably rich, no idea of lean.
I took the scope pic attached with a Hantek HT-25 on for each cylinder
I tried two other used ECUs, no help.
No engine ligth now, but some times has come on with code 12 (no NE signal to ECU)

Please help !

 

I have no idea what the traces represent.

Have you done a compression test?

 

I think that 5th one is telling you to sell.

 

Yes, about six month ago. If I remember correctly all six very close to 155 psi

But I think I had an Aha moment last night.
I did not know this has a PAIR (PULSED AIR SYSTEM) and I think this is the source of all my problems. Also think the Second voltage tells me I ave problems with plugs, but I should correct the PAIR SYTEM air leaks before. I really does not understand how this work. Maybe same principle that air injections systems with an air pump?
I will try to isolate all the air hoses for the PAIR.
Ignition may have an additional problem, why different spaces on secondary ignition?
see attached

Thanks for your post

 

The 3.0L uses a PAIR system instead of a smog pump to load fresh air into the PS exhaust manifold for emissions reduction. The connection to the manifold is fairly straight forward but the plumbing back to the muffler box and the hard metal tubing that runs under the plenum is quite the creation. It is needed to pneumatically tune the flapper valve to pump that air into the exhaust when the vacuum signals from the VSV's dictate and the ECM demands it.

The distributor has signal coils inside two of them are higher up than the third one if I recall correctly. If your distributor is new you would expect the coils to be ok but perhaps they are not or the air gaps are not correctly set and you are getting erratic signals from them. These signal coils basically provide a cam-shaft/crank position triggering function to the ECM but they are well removed from the crankshaft mechanically i.e timing belt etc... The harmonic balancer pulley has a rubber isolation sleeve between the pulley and the hub. If this is some what perished the pulley and timing mark on it may not be representative of the cranks actual position. How has the timing light been working?

Certainly with the temperature increasing as it warms up the overall electrical resistance will increase as well in the wires and connectors and sensing coils and switches. So if it is eventually dying as it gets warm that would indicate a tried electrical connection or sensing coil that is killing the ECM's ability to maintain a running condition because the signal that is needed just isn't getting there. The knock sensor is expensive and from what I have read the OEM Toyota is the only one that works. I had a similar problem with a brand new NGK O2 sensor and the truck would run like crap the second it went closed loop as it warmed up. I put the old tired OEM Denso back in and the problem went away. I was measuring voltages and resistances till the cows came home and never could put my finger on what was wrong with the NGK sensor.

Presumably your reading over a set of Toyota FSM's for functional tests to diagnose things, they are the best in the world in my opinion.

 

Thanks, it makes sense. Yesterday I was sure (No basis!!) that it was running so lean that was the reason for dying at idle.
Well as always as was super wrong and took plugs out to find out they were really fouled with black stuff (fuel I think).

So, I cleaned (they are new iridium 5 months old) and measure engine coolant temperature volts a ECM. Out of specs, so got a new one and will try today.
Maybe another wrong assumption but it makes sense to me that ECU was getting signal for an very cold engine and pumped fuel in like crazy.
Wondering now if my O2 sensors are bad with all this fuel and how can I scope them or test them as per the FSM.
Also yesterday I blocked 100% the EGR in and out plus disconnected and plugged the PAIR valve and rubber hose to the intake manifold.

I will also try to reconnect the old knock sensor as per your experience. Still inside and under the Intake manif.

 

Whao... it is not mine, just trying to help my neighbor for free. Would you share some clues on how you picked up thought to sale it? It will help me learning the scope.
I just got a suggestion from member on scannerdanner website.
He posted this (old but good) free PDF on Scope Analysis and utilization for car diagnostics.
Scope Book 35115.pdf I think written by ALLEN TRAINING PROGRAM
link: http://cody.inlandgps.com/pub/Scope Book 35115.pdf