WickedBlackedtC

So about a week or so, I did an oil change on my 05 Scion tC. I was rushing to catch a World Cup game so I forgot to tighten the oil cap on the engine block. After the game, I drove the car to a local 7-eleven where a bystander got my attention and showed me that there is oil leaking down to the ground. I opened the hood and oil was all over the place. I kept calm, and got a rag, cleaned the engine entirely. Poured some more oil in to get it to the proper level, and tightened the oil cap in. After two days, I started to experience the hesitation, lagging, skipping while accelerating, like what happens in the video. I had to slap on my friend's exhaust so you guys can hear the sound, because on the stock exhaust, you can rarely hear anything. I really need help guys, I dont want to take it to the dealer, pay 200 dollars just for them to tell me to replace the engine. I really appreciate your time.

Note: this is really weird that this problem will go away if the check engine light pops up, no matter what code it's throwing. And it will come back if the check engine light goes away.


Here is the link to the Youtube video that I recorded from my phone. Please turn volume up a little bit if you cant hear the exhaust sound:


Please help me out guys, thank you so much!

torqueTc

iTrader: (11)

Compression check time... and check what codes the ECU is throwing out.

burgandybomber

iTrader: (1)

My car ran like crap when the front O2 sensor went out. If it ends up being poop let me know cuz they are expensive and I have a new one laying around from when I went turbo. Otherwise I would do what torque suggested and do a compression check. Kind of weird the CEL effects the problem. I would also check and see if you knocked any vacuum lines loose like the brake booster or something when you cleaned the bay up.

WickedBlackedtC

Thanks for the suggestions guys, I will definately run those tests. The car threw two codes, and like Bungandybomber said, the codes are O2 sensor code.
One is P2196 O2 sensor signal biased/ Stuck rich Bank 1 Sensor 1.

The other code is P0030, Heater Control, Bank 1 Sensor 1.

I got these two codes from Techstream. The check engine light was not on so OBDII Scanner detected no codes. But the Techstream did.
I dont know if the O2 sensor is the cause of that problem, so please let me know. And please tell me how or where to do compression test. Many thanks in advance.

To Bungandybomber, please pm me your price on that O2 sensor. It is upstream/Bank 1 right? The one on the header right?

Kik

You blew oil all over the engine, I think one of the first things I'd do it start unplugging your electrical connections and clean them out. If oil got into them it could be causing shorts and incorrect signals to the sensors.

burgandybomber

iTrader: (1)

If you could post up that your problem was resolved with an O2 sensor, the community would appreciate it! Hopefully in the future a fellow enthusiast will find this post and be able to extract some knowledge. Kind of a specific problem but the more information we can compile the better!

WickedBlackedtC

Yup! Sorry about that. Ok, so the problem is my upstream O2 sensor was fried (thanks to burgandybomber). I grabbed a new one, tightened it in, and now runs like a champ. Thank you so much for all the suggestions, i realy appreciate it.

kruso

For future reference guy, oil is not a conductor so it will never cause a "short." It's in fact even used an an insulator on certain transformers for that very reason.

criminaltc

Yeah Kik's been known to give random advice.

Kik

For your FYI:

Capacitance. The oil adds capacitance to the connections. The capacitance will cause the signal to deform, instead of nice square waves you'll have something less approximate. If the circuit is level triggered, it's not usually a problem, however edge triggered circuits don't like capacitance on the line because it turns an otherwise clean edge into something outside the parameters of the circuit. In simple terms it deforms the signals on the sensors and causes the ECU to get erroneous readings. Just because they use oil as an insulator for some applications doesn't mean that all electrical or electronics can be run in oil.

"criminaltc, Yeah Kik's been known to give random advice."

I never just give out random advice. I do however give answer to situations that I have similarly been in and what has worked for me. Common sense tells you that if you blow oil all over your engine and your car runs like crap afterward, then clean it up and get the oil off the motor and the electrical. Having oil and grease on your engine does nothing good, it holds heat in the engine and it breaks down the wire insulation and connectors.

criminaltc

I got you. A few months ago, you've had some questionable replies. Haha. I didn't mean any offense.

burgandybomber

iTrader: (1)

He totally meant offense! FIGHT FIGHT FIGHT! lol just glad OP got his problem solved. Always a pain in the a$$ when something just stops working as it should.

criminaltc

I forgot what this thread was even about...

kruso

Duly noted, I'm not sure what that's got to do with my comment. I specifically quoted your incorrect usage of the word "short."

Kik

I guess I could have been more specific. Most people do not understand that signals can be interrupted by contaminates, but they do understand simple things like "Short". I am truly sorry if, by saying one thing and meaning another, that I may have offended someone, and in the future, I'll try to be more specific in the answers or advice I give.