I have a 2010 Prius with 185,000 K, in which I had the local Jiffy Lube change my oil and filter. About 2 days afterwards, the engine started to shake & studder, with no warning lights or codes. I checked the dip stick and it appeared that they overfill my oil by 3/4 quart, I had the Jiffy Lube people drain about 1 quart of oil in order for the oil levels to be in between the maximum & minimum marks of the dip stick. After they did this, the car ran normally with no shake & studder and/or engine hesitations. About one week later, a "check engine" light just went on, which according the manual is a problem with emissions system. The gas cap is on tight, but I haven't look through the throttle body. I'm pretty sure the overfilling of oil created disruptions to the throttle body plate and/or air sensors. I will try to pull DTC codes tonight with my code reader. In the mean time, will continued driving create long term problems with the engine?
I just pulled DTC Code: P0301 I'm hoping that it's not a blown head gasket, taking it to an independent mechanic tomorrow.
So far no updates, I will probably have to wait till after the 4th of July holiday weekend. I'm hoping that it's something simple like dirty fuel injectors, spark plugs/coils/wires, throttle body, EGR valve or MAF sensor. It's currently at the mechanic shop.
Cylinder 1 misfire. Clear the code and see if it comes back. If not, then it's most likely due to oil overfill somehow and is/was a transient problem. In the future avoid quick lube places, they have no idea (and/or don't care) of what they are doing in a lot of cases. Good luck!
3/4 of a quart overfill is not enough to cause a serious issue. It’s just coincidence that this popped up after the oil change. I’d guess that the plugs need replaced. Probably need the slime cleaned out of the TB and the PCV valve changed. If the coolant level is steady then I wouldn’t be concerned with the head gasket.
Yes, I cleared the P0301 code about 48 hours ago and it hasn't reappeared. The engine feels "rough & hesitant" only when accelerating at low RPMs, but performs normally at higher RPMs. I just want to have a mechanic inspect the engine and determine if it's head gasket or other problem. I like to be on top of this before it gets worse.
This sounds real similar to the issue that I had. It wasn't a full on blown headgasket as my mechanic put it, rather a head gasket failure in-between #1 and #2 causing the misfire in #1. I just saw the HyridPit posted on IG about this as well. The one they fixed was a full on blown headgasket. The good news is, if your issue is the same as mine, you wont need new heads, just a quick machining to resurface the current one. As well as replacing a few other parts. Water Pump for preventative, thermostat, things that would have failed in the event a HG did fail completely.
There was no head gasket leakage, one of the fuel injectors was almost completely clogged. We had all 4 fuel injectors inspected & cleaned at an independent shop, then proceeded to clean out the EGR, throttle body, MAF sensor and intake manifold. There was a lot of crap built up after 185,000 miles, considering that I only use top tier gas (ie. Costco) and a Techron Complete Fuel System cleaner every 5000 miles. So far no trouble codes and the car is running normally.
