Check engine light On!

You might be having the exact same problem that I currently have ... I posted about this but haven't gotten any responses ... here's my original post ...

"Hey everyone ... I need some help regarding a P0300 error I'm getting in my 2001 Toyota Corolla. My check engine light came on so I took the car in to the dealership - they told me about the P0300 error and that it could be caused due to a multiple reasons ... bad plugs, low grade fuel etc. I have 65,500 miles on it now.

In addition to the light, I have the follownig problem: When I start my car, the engine fires up instantly, but when I shift it into Drive or Reverse and step on the gas a little, it wants to stall. The car doesn't start rolling immediately. I need to let it run in idle for 30 seconds or so before it will move. It happens more often than not when the car has been out in the sun for a long time. Early morning I have no trouble with it but when I get off work, which is when the cars been in the sun all day, I have the problem without fail."


I've found out from a different forum that this problem is extremely common (unfortunately for us) in 2001 Corolla's and it might be caused due to the following:

"P0300 Error Code is "Random/Multiple Cylinder Misfire Detected".

It could be anything from Timing, O2 sensor to MAF sensor etc. By the way, the MAF sensor is located near the Air filter manifold, not near the catalytic converter. "

I know this isn't a solution for you but it may give you a direction to look into.

01corollauser said:

I Question- You mentioned about the reqd. # of trips....What is the appox. miles or trips that the system takes to reset the light if everything is fine?

I think I am good go to go without spending any money on fixing that issue. But on second thoughts may use some fuel filter cleaner rather then having to replace it soon.

Click to expand...

Well, it'll prolly take forever if I have to explain everything so I'll keep it simple.
The word "trip" is an obd II term. Each monitor(misfire, evap, egr, o2, etc.) runs a trip as long as the enabling criteria for each is met. If all monitors are run during a key on key off cycle, it is called a drive cycle. A trip creates a set of driving conditions that allow a monitor to run.
example- the egr trip monitor will only run if these conditions are present: closed loop. rpm, throttle position, load, vehicle speed, and stft all w/in a specific range.
The purpose of a trip is to control the MIL(or check engine light). Some monitors that detect a fault will store a code and light the MIL in only 1 trip. example: misfire and comprehensive component monitor.
Some monitors that detect a fault will store a code and light the MIL in 2 consecutive trips. example: EVAP monitor.
If a code is stored, the PCM can self erase it, but it must see 3 consecutive trips where the affected monitor runs and passes, or it won't turn off the MIL. Without good trips, the PCM can't tell if a fault has been corrected.
So to answer your question- it depends on the driver. Grandma's car that's only driven once a week for 2 mins. to drive her to bingo night, will never run the catalyst monitor for as long as she owns the car. Also, if you think your fuel filter is clogged, just check fuel press. see if it's low or just replace the filter. And if the light comes back, make sure you pull the code before disconnecting the battery.

Just had mine fixed.

I just got through with the mechanic at a local shop. The corrolla we have is a 2001 with 71000 miles. The code for mine was p1349. This is a VVT error. It is kind of complicated but it basically moves the cam to an advanced or retarded state by way of an oil control solenoid valve. This valve in turn places oil pressure on the VVT and allows the cam to move up to 30 degrees. This was a hard one to diagnose. The local mechanic didn't know much about it. In fact I took it to the local dealer and he said it had a cylinder misfire but couldn't tell me what wass causing. it. When we took the oil solenoid out it was broken. I have one on order now and it looks as though this could be the cause of the stalling and other weird things. The vehical computer sends a 12 volt signal to it to trigger the oil solenoid valve. The PC takes its signal from the throttle sensor, the mapp sensor, the o2 sensor and the temperature sensor. It takes the place of an egr valve on an older vehicle. In fact after reading about this in detail it is a great improvement on what we used to have for cam timing. I hope this helps. It isn't much to check out once you know what to look for. 12 volts fires it. There is a filter directly behind a bolt on the block leading into this that can cause loss of oil flow to the cam which would have the same result. Your local mechanic shouldn't have any problem checking this out for you.