KNOCK SENSOR CODE GOES OFF WHEN THE SENSOR HAS BEEN TESTED OK.
1996 Toyota Tercel
November, 17, 2011 AT 11:22 PM
I am having an issue with my daughters Tercel. It has 110,000 miles on it, My dealership (Honda) has said that the knock sensor is going off likely due to another sound in the engine which in turn activates the check engine light. A little history: My daughter purchased the car private owner in Sept. 2011 my Husband said it need a new oil pan gasket. We asked a friends mechanic to do this. A couple weeks later the engine light came on we then took it took my dealership, At this time the knock sensor was showing up as faulty. We had that replaced we also replaced the belts and water pump because they told us this vehicle had a ton of life left in it. A month later my daughter drove 30min. Away (she only traveled about five miles a day before this) at that time the oil light came on then the car started to drive real rough. She pulled over and found there was no oil that registered on the dip stick. She put two and half quarts of oil in and started on her way at that time the check engine light came on, the car continued to drive rough and now smokes. We took it back to the dealership they changed the oil to a high mileage oil to prevent the burning of oil (This is why the car had no oil in a month after taking to them) and to clog up the piston rings as they seem to think is leaking oil into the engine. Recommend that we add an additive when we need additional oil. They said the check engine light came on due to the oil being so low. After we picked up the car less than two days later the check engine light came on again. We took it back to the dealership now as written above they believe the knock sensor is picking up another sound (they checked the sensor and it is working correctly) and we will need to live with the check engine light on and the smoking with smell. My daughter is only 17 and I really want to get the check engine light off the car because I want to know when something is wrong with the car. Is there something my mechanic could be missing? He usually works on Honda's so maybe it is a Toyota thing?
This could be a twofold problem. Knock sensors will pick up different knocks in an engine like a rod knock or a piece of sheet metal banging against the block. When it goes off it retards the spark in the engine and it runs poorly. It could be a connection problem to the sensor or something worse. The oil burning I wold check the vavle seals first as they may be worn out nd sucking oil into the engine as well as having the pcv system checked for good operation. I fyou have an independent garage that knows toyotas or a toyota dealer instead of a honda dealer where they are more familar with the quirks of the vehicle. All brands have different quirks. But being low on oil like that could mean major engine damage like a rod knock. These can usually be found by sorting the cylinder out to see which if any are knocking. At least an experieinced mechanic in Engine repair could.
November, 21, 2011 AT 8:53 PM
Thank you for your help. I found out Saturday that her engine is leaking oil. She drive 40 miles away and her oil light came on again (it was full when she left). When she got home (after putting three quarts in her car) there was some oil on her car. She usually drives very little (5 miles) and her car does not lose oil just with her driving for long periods (both instances were the 40mile trip). I couple possible causes (not from mechanics just friends) are rear main, vacuum tube from the PCV valve or the oil pan gasket (she did have this supposedly replace right before this started, the reason I say this is the dealership said there was no way the oil was replaced due to the thickness.) If there is any additional help we would appreciate it, even if it is a direction. Thank you!
November, 21, 2011 AT 8:57 PM
Check your pcvvalve, the hose may be plugged and causing the engien to build pressure inside the crankcase. But realistically you will have to clean the engine to find the source of the oil leak. If there are no external leaks suspect the head gasket. You could need valve seals or somehting like piston rings, but a compression test would let you know on that.