Can someone study this waveform and tell me if it looks correct to them. The CKP, CMP sensor look in sync to me but the firing and injector timing look off?
99 Camry 2.2
CH A (BLU)=CKP, CH B (RD)=CMP, CH C (GRN)=Ign Wire 1 sync, CH D (YL)=Inj 1
I'd get a known good waveform for CKP to CMP (if they are off it could cause the firing time of coil to be off also). As for the injector, I believe this engine is port injection which would fire the injector very early (it would not line up with TDC etc).
I have a known good from Kevin Suttorp (off iATN - members.iatn.net/file/view/?id… ) and the Cam/CKP line up as mine does, but both the #1 inj and #1 firing are way different. His is a running waveform, but I don't know if that would make as much difference as I have with this no start. Here's another of mine with #1 ignition event instead of sync.
Opps. Looked at the 99 2.2s and the waveform is still the same as far as CMP/CKP, just don't have one with the #1 spark and Inj. Monday morning I'll breakdown and pull the covers to verify timing. This is something I'm squeezing in between other jobs when I can. Makes it frustrating when I have to keep breaking away from it.
Wow, guess I have to go back to school... I can not imagine why the injector would be pulsed only after the spark plug has fired. It appears to me in your waveform that the ignition burn event is completed before the injector pulse event ever starts.
What kind of a problem are you working on? If you want to check ignition timing with a scope when cranking, you can always use an in-cylinder waveform synced from the ignition. Trying to use an injector is sort of futile, since the injectors can be fires about anywhere in the combustion cycle, depending on engine speed and operating conditions.
Yup! And way better than pulling covers too!
Make sure the engine harness hasn't been flipped over somehow, like during an engine swap.
Counting the teeth on the CKP sprocket, I see that the s… is correct. S… is created by the CKP so it can’t be off unless the sprocket is loose on the crank. Looking at the cam sprocket when at TDC, the pulse should line up with TDC so a few degrees after the s…. The cam pulse in this capture is retarded about 90 degrees from the ign pulse. I’m going off of videos of timing belt installs…
Before pulling any covers an easy way to check for base ignition timing is a relative compression test with a sync. on cylinder 1 ignition. The ignition events should be very close to the peaks of the starter current, since there should be very little timing advance while cranking. Also keep in mind the cam sensor is only monitoring the intake camshaft on this engine. The exhaust cam could be…
Finally was able to get back to this vehicle. Discovered customer had coils plugged up backwards. I had checked that beforehand matching the wiring color of the diagram to coils 1-4 and 2-3 and it was correct. Today we pushed vehicle in and I got to digging. After peeling harness back noticed butt connectors further down. The customer had used the cut harness on the engine we sold them instead…