Loud misfires upon cold start
 

Hey guys, I'm unfortunately making my first post with an issue.

I have a brand new 10 series FRS, with about 800 miles on it.

I've had no issues except for this, when I start the car cold in the morning, for the first 15 seconds of high idle I get 2 - 3 loud misfires, sometimes more sometimes less. No codes are thrown, and after the car gets through the first 30 seconds of high idle it runs perfectly.

I'm actually a certified toyota tech believe it or not, but before I lay this issue on my master tech I wanted to get some info from the forums. Anyone else have this issue or can point me to the correct thread? Thanks again!

I should also clarify - My car was produced after cutoff date for the Rough idle/camshaft sensor/misfire TSB.

maybe DI Seals are bad but i doubt it cuz is not even broken in which means u dont go over 4k rpms



what dealer do u work at?

Competition Toyota (suffolk county) it's broken in, it's been above 4k a few times.

that's the sounds of the precat warming I thought I have the same thing on cold mornings started over winter.

Is it just sound or can you feel it? I have the same thing now with a alpha-tune. It just happens once or twice early in the warmup.

Middle Island?

well post a video of ur car so we can hear the sound

Yup middle island! Whereabouts are you from? And will do, I'll grab a video in the morning after it sits all night

Im from East Quogue

Yea post that Video up


Sent from somewhere

Had the same sound almost every morning last winter and some cold mornings in the fall and spring. Some of the pops are quite loud. I think feldy might be right that it has to do with the cats warming up, because the car runs fine and i have never heard that sound at any other time than initial start-up. Many people on the forums have noticed the sound last winter and I'm sure the topic will pop up more this winter, but I don't remember reading about any resolutions or anyone having it looked at by Toyota.

Yep, my car does the same thing but only during the winter when cold starts are below 35 degrees usually. I thought it was my DI seals too, but it has started perfectly all spring, summer, and so far fall. I heard from a tuner that the "pops" are from the pre cats warming up as well.

Lean misfires during cat light procedure. Normal, but a bit shitty. I'm going to dial it out on mine.

Now are we talking about a sound like champange cork going off under hood? Is tht the pre cats? Cuz i got that today for the first time

Yeah mine are like that. It's captured pretty well here:
http://www.ft86club.com/forums/showp...58&postcount=3

Although mine doesn't pop that much, but the sound is similar. But usually I start driving earlier and I never get those sounds other than on occasional cold startup.

I don't think it's DI seals since I have an 01C cal and still under 5k miles.

The lean misfire thing makes sense - I just switched from E0 to E10 and the first cold startup on E10 it popped more than it ever has before - probably because fuel trims were dialed back for E0, and as a result E10 was probably running a little lean before the ECU had a chance to learn and adjust fuel trims.

Same issues here. Only on really cold mornings, almost sounds like really loud knocks. Car runs just fine when you drive away.

:iono: