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View Full Version : Check engine light on high revs

jayeh
01-22-2014, 08:33 PM
I found this previous post and was wondering if anyone has any more info since I had this happen to me today. http://www.yarisworld.com/forums/showthread.php?t=6133


I was about to merge on to a highway and put my shifter into 2 and floored it and it the car started to accelerate, then around 5k rpm dropped down about 500rpm, flashed the check engine light, I let off and reapplied the gas and it did it again. It happened about 4-5 times along the way too. It was cold out but the car was warmed up.

No codes were shown, no idea what is up. Seems fine on the way home. :iono:

any ideas?
CTScott
01-22-2014, 10:09 PM
Misfires. Either you are due for plugs or you have a coil on the way out. If you have access to a code reader that can read historical as well as current codes you would be able to verify which cylinder the misfire was on.
jayeh
01-22-2014, 10:33 PM
Misfires. Either you are due for plugs or you have a coil on the way out. If you have access to a code reader that can read historical as well as current codes you would be able to verify which cylinder the misfire was on.

There were no codes. :iono:

I've got a scan gauge connected.

It was the first thing I checked after I parked.
CTScott
01-22-2014, 10:40 PM
There were no codes. :iono:

I've got a scan gauge connected.

It was the first thing I checked after I parked.

ScanGauge only shows current not historical codes. You would need a more sophisticated reader for that.
jayeh
01-22-2014, 10:54 PM
ScanGauge only shows current not historical codes. You would need a more sophisticated reader for that.

What is a current code? It only shows me codes while they happen?

Whats the logic behind the gas cap being loose causing the CEL to stay on, but a misfire doesn't even make it stay on?
CTScott
01-22-2014, 10:56 PM
What is a current code? It only shows me codes while they happen?

Correct. A simple scanner will only show codes when the CEL is on. Smarter tools, like TechStream, show codes that occurred previously, but since have self cleared.
contraband831
01-23-2014, 12:58 PM
Had this happen to me a few years back and in my case it was the spark plugs, you may want to check them.
jayeh
01-24-2014, 09:26 PM
Had this happen to me a few years back and in my case it was the spark plugs, you may want to check them.

New plugs are on order and they'll be here by the time I have a chance to change them!

Thanks guys.