Gas engine chugs badly when stopping and starting.

Discussion in 'Gen 2 Prius Main Forum' started by ozarkretiree, Jan 20, 2020.

  1. ozarkretiree

    ozarkretiree Junior Member

    Joined:
    Oct 10, 2008
    54
    13
    0
    Location:
    Missouri
    Vehicle:
    2007 Prius
    Model:
    Four Touring
    OBD was showing misfires in all 4 cylinders so I had the plugs changed and the cat converter drilled and checked. Have also ran 6 bottles of SeaForm through in case the throttle plate was dirty. Not i am wondering if the ECM could be causing the problem since it only happens during stop/start actions. Any suggestions will be appreciated to help me avoid a dealership visit. A friend suggested the coils could be bad but that seems wrong given how the engine is acting. The coils were replaced about 50K miles ago. Current mileage is 238K.
     
  2. davecook89t

    davecook89t Active Member

    Joined:
    May 10, 2016
    583
    429
    0
    Location:
    Washington State, Florida
    Vehicle:
    2017 Prius
    Model:
    Four Touring
    I have never used SeaFoam to clean the throttle plate, perhaps it works well enough, but it is relatively easy (although somewhat tedious) to clean with some Q tips soaked in isopranol. Also, it is easy enough to check whether SeaFoam did the job. Just remove the air cleaner and shine a flashlight down there. It's best to eliminate that as the cause before spending time and money to dig further.
     
  3. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    3,707
    1,351
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    I learned last week that those misfires and related flickering of check engine light are the first thing that shows up when you're 2 quarts or more low on oil and crankcase bearings start to fail... So if I were you I'd start looking at oil level, oil pressure, crankcase sensors & related codes.
     
    davecook89t likes this.
  4. ozarkretiree

    ozarkretiree Junior Member

    Joined:
    Oct 10, 2008
    54
    13
    0
    Location:
    Missouri
    Vehicle:
    2007 Prius
    Model:
    Four Touring
    Thanks for both
    Thanks for the responses from DaveCook 89t and Prius Camper. I will check both of those but I know my oil is fine.
     
    PriusCamper and davecook89t like this.
  5. ozarkretiree

    ozarkretiree Junior Member

    Joined:
    Oct 10, 2008
    54
    13
    0
    Location:
    Missouri
    Vehicle:
    2007 Prius
    Model:
    Four Touring
     
  6. ozarkretiree

    ozarkretiree Junior Member

    Joined:
    Oct 10, 2008
    54
    13
    0
    Location:
    Missouri
    Vehicle:
    2007 Prius
    Model:
    Four Touring
    Update after reluctantly going to Toyota dealership in Joplin. Compression low in 2 cylinders. 2 and 4 have 105 PSI but 1 and 3 have 70. Dealer recommends engine replacement with salvage engine for $4,168.40. It seems to be running well so I will just change oil and replace with a heavier weight and suffer the hit on fuel efficiency and use this great car for local run around. Any suggestions on the oil to use?
     
  7. davecook89t

    davecook89t Active Member

    Joined:
    May 10, 2016
    583
    429
    0
    Location:
    Washington State, Florida
    Vehicle:
    2017 Prius
    Model:
    Four Touring
    I would still use a multi-grade dino oil, something like 10-30W or 10-40W. Starting up in the cold, it will act as a 10 weight to keep your engine lubricated, but once the engine warms up, it will thicken up to 30 or 40W, to limit the leakage into your combustion chambers. At this point, you would want to go with the cheapest bulk oil you can find, probably the store brand.
     
    ozarkretiree likes this.
  8. ozarkretiree

    ozarkretiree Junior Member

    Joined:
    Oct 10, 2008
    54
    13
    0
    Location:
    Missouri
    Vehicle:
    2007 Prius
    Model:
    Four Touring
    Thanks, appreciate the suggestion.
     
  9. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    3,707
    1,351
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    Read up on DIY "Piston soak" to maximize lifespan of engine. The stealership won't do that, but you can, or a local non-dealer mechanic can.
     
    davecook89t likes this.
Loading...