Dr-Gonzo

A coupe of weeks ago, I posted this problem (which was an easy enough fix):
https://www.scionlife.com/forums/sho...d.php?t=200949

Tonight, I boosted into 4th and my CEL started flashing. It went away after about 15 seconds. This isn't good, I know, but I got it home fine and it didn't seem to have any driving issues. I didn't feel or hear anything unusual, but the consensus seems to be that I misfired. I didn't get any codes to read, which bothers me too.

When I got home, I disconnected the battery to clear the ECU and started her back up with no issues, but my STFTs were waaaaay too high, at around +15 - +18 while idling. LTFTs were zeroed out.

My first thought is that when my charge pipe blew off and I dumped a ton of gas (see previous thread), I think I've fouled a plug. Another thing to note is that my map runs a tad rich (done by an Evo tuner), and I backfire if I hard accelerate, let off the gas, then get back on it. I usually get a loud pop once I get back on the gas, but only if I've done a hard acceleration. Maybe my cat's going too.

Regardless, she's parked and going to the shop on Saturday, but what are y'alls thoughts?

Thanks as always.

trd07tc

iTrader: (-1)

was the car misfiring right before the cel began flashing?

go buy some plugs there like $3 each

Dr-Gonzo

I felt a slight stutter, but it didn't feel like a serious problem. If anything, it just felt like a poor shift.

The main thing that bothers me is the short fuel trims and how they've jumped way up, even after a reset. Is that indicative of bad plugs? Why is my ecu adding so much fuel now?

I'll start by changing out the plugs to see what happens.

trd07tc

iTrader: (-1)

what were your wideband readings around the time of the misfire

Dr-Gonzo

They were on the rich side, 11-13. But like a said in the original post, my map runs rich after a hard acceleration, sometimes pegging 10 for a split second. It's like the injector duty cycle continues for a moment after I let off the throttle, and when I get back on it I backfire the excess. Not ideal, but running a cat along with pull through maf add to the issue I think.

What about the increase in STFTs?

bigG2148

check ur spark plug for oil. if there is any oil its not looking to good. but i could just be that u need new plugs

Dr-Gonzo

Nope, no oil on the plugs. They were in good condition, but I swapped them out for new ones.

I think the problem is the harness crosstalk that occurs with the FIC under high RPMs. Looks like I need to do the resistor mod.

I got the STFTs to clear after swapping the plugs. Just needed the battery to be disconnected a little longer.