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Replaced head gasket, now P3190

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by jackc04, Dec 5, 2021.

  1. jackc04

    jackc04 Junior Member

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    I replaced the head gasket on my 2013 Toyota Prius because coolant was leaking into cylinder 1. I had the head machined, and followed the steps in that gasket masters video. When the job was done and I started the car, I got a P3190 DTC "poor engine power", and the engine started but sounded labored, sick, very low RPMs. I also got a strong odor of something I have never smelled before, kind of like a gasoline smell but not 100%.

    I stupidly skipped the step where I was supposed to lock the two camshafts in place before I took the chain off, and of course the camshafts moved as did the crankshaft. I followed what I thought were the right steps when putting on the new timing chain, I think I lined up all the marks on the chain to the marks on the exhaust camshaft (that tick lines up with the colored link on the chain, and the "E" is 90 degrees to the right of the tick), and the tick on the intake camshaft is lined up with the other colored link on the chain, and the cylinder 1 is top dead center, and the tick on the crankshaft is lined up with the mark on the chain. Seems "foolproof" to me. Good thing as I am a fool evidently.

    Does this seem like a timing issue? Did I miss any critical steps in setting the timing of the two camshafts and the crankshaft? This is maybe a dumb question, but when the chain is disconnected, there is only ONE TDC position of the crankshaft (cylinder 1 at the top) right? The actual crankshaft has no differentiation of a compression and exhaust stroke right? The definition of compression vs exhaust stroke is a function of the position of all three shafts together, the two cams AND the crankshaft, right? A buddy of mine is insisting that the crankshaft itself, disconnected from the chain has two TDC positions, one for compression and one for exhaust. That makes zero sense to me based on my meager understanding of how the crankshaft works.

    Any help would be greatly appreciated! Thanks
     
  2. jackc04

    jackc04 Junior Member

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    Regarding my confusion about whether there is one TDC position of the crank or two (compression and exhaust), I would think that with the chain disconnected, you could put the crank in a position where cylinder 1 is at the top, and so far as the crankshaft is concerned, that position can be used for compression or exhaust stroke, its the same stroke so far as the mechanics of the crankshaft and pistons are concerned. Right?
     
  3. mr_guy_mann

    mr_guy_mann Senior Member

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    Yes, when the crankshaft is by itself, there is only TDC for a given cylinder. If the head was off (so you couldn't have any piston to valve contact), you could turn the crank 360° and it would be the "same" position. You can't define compression or exhaust stroke until you have the camshafts synchronized to control valve events.

    Now, your engine- AFAIK you need cylinder 1 at TDC, then all 3 special links must match up to the marks on the crank and cam sprockets. Then once the timing cover is installed you have to install and unlock the chain tensioner before trying to start the engine. After unlocking the tensioner I would manually turn the engine with a socket on the crank pulley several revolutions to see if cam sprockets still "point the same way" at the correct TDC position (the colored links won't line up again until the engine goes many revs).

    Since you appear to have a timing problem, in addition to getting things back to where they should be, you have to inspect for possible valve damage. I would get a cheap videoscope and look down the spark plug holes for any shiny marks on the pistons.

    Posted via the PriusChat mobile app.
     
  4. 2010moneypit?

    2010moneypit? Active Member

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    you said that that engine sounded sick and labored. It was probably just cranking over off the high voltage battery. The way the Prius cranks over is not like a standard starter.
    I agree sounds like your timing marks Are not correct. It is also possible that you left something disconnected or the pins got damaged when you were reconnecting connectors check all your connections carefully.
     
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  5. ttou68

    ttou68 Active Member

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    I would also check the fuel line connection if there's a strong gasoline smell...
    One of the possible issue of P3190 is low fuel pressure..

    Posted via the PriusChat mobile app.
     
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  6. jackc04

    jackc04 Junior Member

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    Thank you. I think I was mistaken when I said I smelled something. I'm guessing the electric motor is just turning the crank, it never turns for more then 30 seconds or so. I cleaned the MAF and Throttle body, but then forgot to reattach thr throttle body sensor and tried to start it and it cranked for a half second and then stopped. I reattached the throttle body sensor now nothing, no attempt to crank. I've cranked the engine maybe 6 times so far. You don't think I could have drained the EV battery do you? How much of a problem would that be? I need to pull the current DTCs maybe there is another reason why it's not even attempting to crank. I hope it's not because the EV battery is dead. What options would I have if that's the case? How do you diagnose a dead EV battery?
     
  7. 2010moneypit?

    2010moneypit? Active Member

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    What does the dash say? Is the battery totally depleted on the dash?
     
  8. jackc04

    jackc04 Junior Member

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    Dash says one line. I've never seen below two lines so that's scary. Dr. PRIUS says battery charge 16%. I assume Dr. Prius is measuring the EV battery power. Yikes I better not try to start it again until I'm sure. I was able to reattach the throttle body sensor and that dtc went away. Now back to the p3190 and and p0a0f. I'm ready to give up and tow to a mechanic, I can't think of anything else that could be wrong
     
  9. 2010moneypit?

    2010moneypit? Active Member

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    Towing to a mechanic might be best unfortunately. Your hybrid battery is very low it may need to be grid charged if you have the capability to do that I would say continue working on it but first get that battery charged.
     
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  10. jackc04

    jackc04 Junior Member

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    just an update (in case this ever helps anyone else). I finally gave up and took the car to a mechanic. He quickly found that I neglected to reconnect the PCV hose under the intake manifold properly. He connected it, and voila, the engine started running. Since I cleaned the throttle body, he also had to perform an idle re-learn on the throttle body. Everything is working great now.