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Wow thanks so much for that info. I'm a parts counterman at my toyota dealer so I'll look into this tomorrow. Also I'm going to check the toothed sprocket that the crank sensor reads to make sure a tooth wasn't bent or something when they transferred the toothed sprocket from my old engine to the replacement engine. I'll remove the crank sensor and use my new boroscope in the hole. Anyone know how hard it is to rotate the engine slowly via a front crankshaft bolt?After the plug swap I'd look a the electrical side of the coils. There is a sub harness from the main engine bay harness on each bank that is for the coils that is cheap enough to just swap at ~$20 per side to rule out that leg of the wiring before you parts cannon the engine bay with new hardware unless you want to spent the time with a fluke ringing out and hand over hand checking the harness. I'd ring it out first but it is cheap enough to do the coil side and the main harness is like $900. I'd suspect the shop pinched a wire installing the engine or the harness was damaged shipping or you have a vacuum leak from a crap hose or a bulk leak from an open nipple.
(I think it the coil subharness is 8212634021 and 8212734050?)
Lol. Well put. Just to clarify I never feel a misfire. Butter smooth until the computer goes into misfire protection mode. Only then is it rough as it shuts down the 2 cylinders . Spark plugs brand new. I did shotgun a crank sensor but it didn't help. The used engine arrived with no flex plate and no toothed sprocket so they had to swap that from my original engine. Again, never feel any roughness or stumble. Pictured is my replacement engine as it arrivedIf you feel it stumble I'd start at ignition and plugs first before thinking the reluctor wheel is bad/bent (not sure why you'd ever change one unless the sensor ground into it). I doubt they pulled it unless they were going into a RMS replacement prior to dropping the block in. I think it is just forward of the flex plate on a 5.7? If the stumble is felt only at idle and intermittent I doubt the wheel is bad. If you had a missfire code and no stumble I'd start poking sensors earlier in the process but not as my first stop on this train.
Start at new plugs in the problem jugs then go from there. Try throwing a timing light on the problem jug when the problem is occurring to confirm dropped spark then work back from there to see where the trigger signal is intermittent.
If your at the parts counter- go by the grey beards lunch and a beer and talk shop- then bum the tech stream system and start diagnosing after the bays are shut down for the night. A blind parts cannon approach might fix this but will be $$$.
You are the exact person I need looking at this. It's a shame that I work at a toyota dealer and can't find a technician that would do what you are suggesting. Let me try with a different technician maybe. Totally frustrating. You near new jersey?Thought I read that you mentioned a physical stumble- That changes things but maybe not for the better/easier - stick your finger in the crank sensor hole and see if the reluctor can move or sensor is loose/installed backwards when at TDC? (not sure it can go on backwards) Can you get to the TC from the lower access plate to see if it is loose? P30x Misfire DTC is a reading of crank and cam position sensors looking at variations in RPM/frequency/phase. Make sure the two sensors don't have bent pins and are seated in their connectors tightly then start working your way to the engine harness but youre goign to need to run it on techstream.
I think you need to get to know the FSM and techstream in the biblical fashion to find your problem if the reluctor and sensor are physically good. It starts with the old testimate of checking PCV, new plugs and meggering them, etc. then goes to the new testimate good stuff like using techstream in check mode and run the misfire load and missfire RPM test with freeze frame enabled and run the missfire count/margins with the cat overtemp alarms disabled.
Nowhere near NJ and I'd rather sell bibles door to door in eastern afghanistan than step foot on the east coast.You
You are the exact person I need looking at this. It's a shame that I work at a toyota dealer and can't find a technician that would do what you are suggesting. Let me try with a different technician maybe. Totally frustrating. You near new jersey?
Thought I read that you mentioned a physical stumble- That changes things but maybe not for the better/easier - stick your finger in the crank sensor hole and see if the reluctor can move or sensor is loose/installed backwards when at TDC? (not sure it can go on backwards) Can you get to the TC from the lower access plate to see if it is loose? P30x Misfire DTC is a reading of crank and cam position sensors looking at variations in RPM/frequency/phase. Make sure the two sensors don't have bent pins and are seated in their connectors tightly then start working your way to the engine harness but youre goign to need to run it on techstream.
I think you need to get to know the FSM and techstream in the biblical fashion to find your problem if the reluctor and sensor are physically good. It starts with the old testimate of checking PCV, new plugs and meggering them, etc. then goes to the new testimate good stuff like using techstream in check mode and run the misfire load and missfire RPM test with freeze frame enabled and run the missfire count/margins with the cat overtemp alarms disabled.
This needs to go all the way thru the diagnostic procedure and the results of each step listed - There are a bunch or ways to piss off a factory ECU and it is worse after major changes like an engine swap. I can see a couple ways this could be happening but the margin test will show if it is systemic and these two jugs are just the two that are barely over the x of 1000 revolutions (45'ish/1000 as I recall?) of misfiring and the remainder are just under or if these two are the only whacky jugs and they are way dead when they die or intermittently go in and out. Also would want to see if cat temp goes up before the MIL fires the DTC or if this is logged only off the RPM data. Could be crank reluctor isn't indexed correctly and idle timing rolls in and you end up thumping all the cylinders but these two trip it over the edge into OL fuel map before the others error out (I don't know the mechanical indexing of the crank flange aft). Closed loop max lean idle settings dial in and these two injectors are slightly plugged causing lean pings (IR gun the primary pipes or swap injectors around on the rails?). Or it is something in the coil trigger lines, grounds, bad plugs, oiled plug ceramic/boot/pack, bad MAP/MAS, Vac leak, or anthying in the harness that got pinched dropping in the engine and is now intermittent short/open. I lean towards install/shipping damage on the wiring or a vac leak but the freeze frame data grabs should point to the problem.I like the idea of checking the crankshaft position sensor. Two different pistons on two different banks, only associated by firing order on each bank suggests it could be related by the crankshaft. Which spins twice for the full firing cycle of the engine.
As the engine is butter smooth, until the moment the ECU thinks there's a problem, it also lends to the idea that it's a false sensor/signal issue that only arises intermittently when the engine is hot.
With the sensor being at the bottom of the engine, albeit behind a small shield, I can see shipping and handling of the motor potentially compromising the sensor?
Certainly possible- I think the ecu checks correlation between crank and cam pulses (DTC P0019 looks to see if the cam and VVTI are wonky to crank position). Looks like it is a stamped part with angled out teeth so you can pull the sensor and see it and see where the gap starts relative to TDC. Wonder if you could install it flipped with the teeth against the flex plate? Doesn't explain the intermittent issue and only 2 jugs. but this is all internet pin the tail work until you dig into the testing. The reluctor has an index hole and the crank has a pin/button inside the flex plate bolt pattern. You should be able to set the engine at TDC and see if the tone ring gap is installed correctlyCan the relector ring only go on one way? What if they didn't position it correctly? Is it keyed,?
I suppose but have to be at a different time.can you turn your bore scope and look in the bottom of the bell housing?
I'll just let these pics do the talking
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Did you wash your hand
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Exactly. I will be reaching out to the install shop tomorrow and asking the same question. You can see the big gap on the scope represents the intentional area without 2 teeth for TDC location. Then it comes to the 1/2 tooth. This makes that dead zone wider than 2 teeth worth which the ecu interprets as the engine speed slowing down which it isnt really slowing down based on other sensors. The only conclusion the ecu makes is that it's a misfire. That broken tooth correlates with cylinder 4 which is shared with cylinder 7. When those two cylinders are at TDC (which happens at the same time, that broken tooth is lined up with the crank position sensor tip. Crazy s*** I tell yaHoly crap. Is that the smoking gun? How does the reluctor even get damaged like that?