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I NEED HELP!! MECHANICS VERY WELCOME. CHANGED INJECTORS AND NOW CONSTANT MISFIRING

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Iamnotarobot, Mar 29, 2022.

  1. Iamnotarobot

    Iamnotarobot Junior Member

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    Well the compression test is not useless when we are talking about rings leaking. I am just saying if oil consumption is in spec and compression in spec I am not going to worry about rebuilding.

    The head gasket not mixing on this car I did not know. But even if it were leaking into the cylinders wouldn't my coolant level should be dropping.

    my coolant was changes at around 90 or 95,000 miles and I have not added anything since. Coolant is at cold and has been at cold right above the FULL letters on the tank.

    Can the head gasket be bad if there is no coolant leak and no fluids mixing??
     
  2. rjparker

    rjparker Tu Humilde Sirviente

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  3. Iamnotarobot

    Iamnotarobot Junior Member

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    Ok so let's say you are absolutely right and I need a new engine, what if I am on a budget. Can you think of any ways to get my car back to the way it was before I removed the injectors?
     
  4. ChapmanF

    ChapmanF Senior Member

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    Well, I didn't say "professional" diagnostician, necessarily, just "experienced" one.

    This kind of engine diagnosis can eventually end up in the wheelhouse of someone with those kinds of skills, which aren't Toyota-specific and don't require Toyota-specific tools.

    (Because you mentioned a "$10,000 toyota computer", if you did want a rig to run Toyota Techstream on, it wouldn't be anywhere near that much. An old laptop and even if you want their officially tested and supported dongle, that's just $500ish, and the software activation starts at $65 for two days to be official with that.)

    But some issues move beyond what a laptop and OBD software can do for you. An experienced old-school tech probably also has stuff like an oscilloscope and can use it to learn things like whether the coils and plugs are doing what they ought to or not, without having to swap things willy-nilly.

    Those are the kinds of tools where the tech's experience comes into play. Something like Techstream is really an attempt by Toyota to make a bunch of diagnosis accessible to less experienced techs. The software can measure a bunch of things for you, step you through tests, and so on, while you just point and click on things.

    By contrast, the more old-school instruments like oscilloscopes are way more general-purpose, they don't come in special Toyota flavors, and can be used to check all kinds of things on all kinds of cars. But they won't hold the tech's hand the way something like Techstream does; all they do is make wiggly pictures on a screen, and it's up to the human to know what use to make of that.
     
  5. Iamnotarobot

    Iamnotarobot Junior Member

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    Ok so I will not let this pitter out. I will post until the repair is done. I hate when threads die and no one resolves the issue.

    I started pulling emissions parts and one by one looking clean! PCV valve clean and holding pressure, throttle body clean, EGR tube and EGR cooler exit port clean, intake manifold clean. I installed a catch can on the pcv system and I would say it is working very well. I kind of expected this all to be pretty clean. It has been 100,000 miles since I last cleaned emission system and replaced manifold. Most of those miles had a catch can installed.

    Looking in the intake channels on the head you could easily see the #1 intake valves were in a pool of fuel. Looks like #1 Fuel injector is bad. I think.
    I will order new injectors because they all have such high mileage. I will put in the coils, I put in new plugs I had on the shelf, and because I have it apart I will clean all the emissions parts. When everything is running I will post my compression #'s too.

    My goal with this "service" was to try and improve 40mpg which I have had for many years now. Maybe since about 130k it started to suffer then around 170k it was down to 40mpg. I normally would get 50mpg in the same conditions. I have owned the car since new 2012.

    Maybe I should test the egr valve?? Anyone know the process for that??
     
  6. Iamnotarobot

    Iamnotarobot Junior Member

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    I am quick to post haha. Maybe because the #1 injector was leaking after the battery was connected the computer is dumping fuel to compensate. I fixed the leak and now it still is dumping fuel in the #1..???? Or is this normal when the engine shuts off and one cylinder has fuel ready on the valves?? Anyone know? I do not remember fuel in any cylinder last time I was in here.
    Should I wait to order injectors??? What does the room think??
     
  7. 2010moneypit?

    2010moneypit? Active Member

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    Are you sure it’s fuel not coolant? I know you said the coolant level is not dropping. However it could be going down a very small amount. I ended up marking the coolant surge tank with a sharpie. I always check it with a cold engine.

    AS far as the lost MPG goes did you say you have replaced your hybrid battery?
     
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  8. Iamnotarobot

    Iamnotarobot Junior Member

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    The coolant level has been holding for over 100,000 miles at the top of the word FULL on the tank when cold.

    I used needle nose pliers to lower a paper towel in the intake on the head and dried it out. It was gas. I do not think coolant could make it in through the intake valves due to the air flows into the cylinder (if you are thinking head gasket).
    All plugs look the same too except #1 was wet but I think that is because of the excess fuel going in. Plugs looked a little rich but good and with the loss of MPG I would suspect that is why, I am running rich or what I am hoping is that my ignition coils are not as efficient as they used to be.
     
    #28 Iamnotarobot, Mar 31, 2022
    Last edited: Mar 31, 2022
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  9. Iamnotarobot

    Iamnotarobot Junior Member

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    The Hybrid Battery has not been changed. I may get the prius battery app to check the health. You might be on to something there.
     
  10. 2010moneypit?

    2010moneypit? Active Member

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    That may be your loss in MPG. 10 year old battery that’s lots of cycles.
    You may want to move injector one to another cylinder to see if the problem follows the injector.
     
    Iamnotarobot likes this.
  11. Iamnotarobot

    Iamnotarobot Junior Member

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    I agree completely. I am eager to see the app test results now. Maybe it has a bad cell or two. Thanks for the idea!!

    Maybe I will move the injector, but I think there is a problem there so I will just do all four. When the timing opens the intake valves the fuel sprays and it should have been sucked into the combustion chamber.
     
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  12. Tombukt2

    Tombukt2 Senior Member

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    I just got done with this had a guy try to replace the head gasket the guy that worked at the Toyota dealer who did the work didn't notice when he pulled off the head that cylinders won three and four were beautiful but cylinder number 2 look like is trying to flip over and it's bore literally the right side of the piston on the thrust side is up higher then it is on the left and it is disconnected from the connecting rod but the engine can spin around and round and round at speed without hitting anything very strange this guy couldn't see this i look in the hole immediately and see this and i'm like oh my God so i had to replace the engine
     
  13. Iamnotarobot

    Iamnotarobot Junior Member

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    OK I am back and the car is running great! The #1 Cylinder Injector was flooding the engine.
    Advance Auto Parts - Down for Maintenance
    $200 after core refund and %15 off coupon. $136 for new ignition coils. Plugs I put in were on the shelf. I am sub $400 even with the ebay injector cleaning. Not $1600 as RJ was trying to say. I have not thrown parts on this willy nilly either. I took a logical approach assuming it was the injectors. Because they were the longest shipping I started to clean the emissions system, manifold, and put in new coils.

    Before I put new injectors in the car it ran a lot better after the new coils, but still began to stumble. I wanted to test if they made a notable difference and there was.
    I assumed because the car ran great and no head gasket symptoms or loss of power from a rod failure (Sorry Tombukt2), that it was the injectors because at the start of this the car was running fine no issues other than morning rattle starts (which I believe in some cases like mine the injector/ injectors and coils are a main factor.) Also the flooded 1 intake port was a giveaway on the #1 injector.

    I took photos of my cylinders through the spark plug tubes and you all can judge yourselves the health, but I do not see anything abnormal to this car. Shown #1-4. They seem to get progressively more dirty from 1-4 because of the blocked manifold pathways that feed in under the injectors. A less clean injection of fuel less efficient burn leads to more carbon ( I think ;) ). I have started the last 20k miles putting in Redline in tank additive and it may have started to clean...?? I know techron is awesome and this stuff has the highest amount on the market as I understand.

    [​IMG]
    [​IMG]
    [​IMG]
    [​IMG]

    So this was all to find out if I can improve my MPG on this 210,000 mile 2012 Prius. It was about 41mpg before this. I will test over the next week and see what I can get.
    I will test with the original o2 sensor and then put in the new one I bought and test for any differences.
    Then I will test compression of each cylinder to see anything notable.

    Oh and when I said I saw smoke. It was just wd40 I sprayed on the o2 bung burning off. LOL I was tired ....
     
  14. Iamnotarobot

    Iamnotarobot Junior Member

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    Trip 1 with original factory o2 sensor: 16.2 mile trip @55mph 4 stop signs (cons 51.7 mpg, avg 50mph, 73 deg)
    Trip 2 with new amazon o2 sensor: 16.2 mile trip @55mph 4 stop signs (cons 51.6 mpg, avg 49mpg, 72 deg last 5 min 71-70)

    [​IMG]
    [​IMG]

    So I do not know how long this new sensor will last but it seems to be dialed in exactly to factory. Would a new bosche or toyota o2 do better? Maybe, but I doubt it.

    So 211,000 trying to get better gas mileage from new injectors, new plugs, and new ignition coils. Did it work? Well I will post that with my compression test numbers next. I will say this, I drive all over and I have not seen over 50mpg since maybe 2014 or maybe 150,000 lol.

    I will also follow up about the shake rattle and well more rattle from the missing in the morning. I bought the car new in 2012 and the first week I would hear the trans rattle backing out of my garage on cold start. Called the dealer and they said check your manual, it is the trans and normal. It was hard to believe. Anyway so far all I have heard is a brief clunk clunk and smooth idle. It reminded me of when it was new. Time will tell, but I will post all the data in a few days.
     
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  15. Iamnotarobot

    Iamnotarobot Junior Member

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    Ok a few days longer than expected. So the car has gone through a couple tanks of gas. My wife was 35-38mpg and now averaging around 40-44 and I have been around 46. I have not driven the car much I expect I could get 48.
    No matter how you look at it injectors, ignition coils, cleaning all the emmisions system, and new plugs (a good tuneup) raised my wifes MPG 12.5% - 15.6% roughly. I used to get 40-41mpg and now easily 46mpg that is a %10.8 - %13 gain. I feel I could get 48mpg again.

    I put the car back together and did not get the compression #'s yet, but for future posterity I will post here again soon with the numbers. And more detailed MPG improvements once I put a couple tanks in myself.

    These repairs all in cost about $400. For a 10-15% gain in fuel economy and almost no rattles anymore it is amazing! Now that the weather is warm I have not heard a rattle in the last dozen or so trips. When it was still cold mornings there was a split second clunk clunk and quiet.
    I can not believe I did not do this back around 130-150,000 miles. I would have saved a lot of gas and a lot less crazy rattles everywhere I go.

    Thank you everyone for the help and input, it is very much appreciated. :)
     
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