Check engine light on high revs - Toyota Yaris Forums

jayeh · 01-22-2014, 07:33 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.

any ideas?

CTScott · 01-22-2014, 09:09 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, 09:33 PM

Quote:

Originally Posted by CTScott

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.

I've got a scan gauge connected.

It was the first thing I checked after I parked.

CTScott · 01-22-2014, 09:40 PM

Quote:

Originally Posted by jayeh

There were no codes.

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, 09:54 PM

Quote:

Originally Posted by CTScott

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, 09:56 PM

Quote:

Originally Posted by jayeh

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, 11:58 AM

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, 08:26 PM

Quote:

Originally Posted by contraband831

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.

01-22-2014, 07:33 PM	#1
jayeh View User's Garage Drives: '08 Yaris LB Join Date: Jan 2012 Location: British Columbia, Canada Posts: 328	Check engine light on high revs 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. any ideas? __________________

01-22-2014, 09:09 PM	#2
CTScott ULTIMATE View User's Garage Drives: 09 5dr LB, 2x 08 3dr LB Join Date: Oct 2008 Location: USA, CT Posts: 13,460	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. __________________

01-23-2014, 11:58 AM	#7
contraband831 El Huevo Drives: 2007 Liftback Join Date: Aug 2006 Location: CEN*CAL Posts: 959	Had this happen to me a few years back and in my case it was the spark plugs, you may want to check them. __________________

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Check Engine light and advance track light on	20104dr	DIY / Maintenance / Service	2	10-31-2013 09:59 PM
Check Engine Light on at 32k kilometers?	caper26	DIY / Maintenance / Service	21	10-16-2013 12:27 PM
Cold air intake....check engine light on...???	JohnnyMalice	Performance Modifications	4	04-29-2012 09:46 PM
NEED ENGINE CHECK LIGHT CODE LIST	Attitude	Forced Induction Forum	12	04-11-2011 06:38 PM
Check engine light	Mr Yarisman	Performance Modifications	7	10-24-2009 11:10 PM