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.
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.
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.
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.
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?
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.
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.
