6G Celicas Forums

At idle my maf is 7.1 an my timing is 15.5 at 880rpm

O2 sensor will throw a flashing CEL, not because the O2 code but because the AFR gets so jacked up it causes a severe misfire across an entire bank of cylinders.
Just because the O2 sensor is bad doesnt mean he will get an O2 sensor code unless its shorted or open. He can try to graph the zero crossings on the with the scanner but Im gonna guess his fuel trim on that side is gonna be pretty far off.

New little fun fun fact i can disconnect the sparkplugs to 1,3,5 she still sounds an revs the same!!!

coil to rear bank dead?

No the coils seem to be firing but i think the plug wires arent getting spark to the bank

Check each individual plug for spark to ensure that you're getting spark. I would bet that the rich smell that you're smelling is fuel blowing straight through the exhaust. Nonetheless, after checking for spark remove those three plugs and see if fuel blows out of each cylinder when you crank it over. Or you might get lucky and there will be fuel on each plug when you take them out. If the plugs each fire perfectly and you can confirm fuel in each cylinder, then that leaves only timing.

Edit: I forgot to say, pull the fuel pump relay before checking for spark. Definitely don't want fuel blowing out of the cylinder with a spark plug firing right there.

This post has been edited by richee3: May 3, 2012 - 10:42 AM

Its all sounds alot easyer than it is since the 3in question have a intake hanging over them lol

Didnt you say you had somehow rigged the O2 sensor in an earlier post? Was it the bank one sensor?

Yes an yes edy
I changed out the plug wires an checked spark an im getting spark to all 6 cyl
Im about to chabg out the e3 plugs for the stock coppers an put in the new fuel filter

Checked plug on cyl1 an it was loose so im going to try an tighten them up tonight after work an change my fuel filter an see what happens

Getting closer, slowly but surely.

The pre-cat O2 sensor control fuel to air ratio adjustments for the cylinder bank its installed on. An exhaust leak, an improperly installed O2 sensor(I/E sticking to far into or to far out of the exhaust pipe), the wrong O2 sensor for the engine or more specifically the ECU, or faulty wiring will cause inaccurate readings of the air to fuel ratio.
The computer would recognize a shorted/open circuit or improper response time from the O2 sensor and display a fault code. But sometimes, the ECU does not detect the malfunction of the O2 sensor and attempts to adjust the fuel trim to match the inaccurate readings. This causes a misfire condition of the cylinder bank with the incorrect functioning O2 sensor, either lean or rich.

The chances of all three plugs or wires being defective of only one cylinder bank are slim. By my calculations there is only a 4% probability that IF 3 plugs or wires are misfiring on a V6 THAT they are all located on the same cylinder bank. 96% of the time the misfiring plugs/wires will be spread between both banks.
Of course, unless you physically removed the plugs yourself there is an increased chance that some jackass before you only replaced the bank 2 plugs because they were to lazy to remove the intake manifold.

The chances of a coil malfuntion causing all three bank one cylinders to misfire is next to 0% because of the wasted spark system.

What was the issue you had with the O2 sensor in detail?

If he totally unplugs the 02 sensor from the wiring harness, it should default to stock trim levels. Unplugging it totally should let him know if the ecu is getting f-ed up by a bad sensor...

Ok ill unplug the bank one o2 sensor tonight
Edy-when i was installing the motor in the original o2 sensor was getting hung up on the streering rack an in the process of trying to remove it one of the wires got frayed pretty bad an didnt look fixable or useable so i replaced it with a bank 2 sensor from the junkyard since it was easiest to get to.

Maybe it is the O2 sensor. Wouldn't think which bank would matter, upstream O2 sensor should be an upstream O2 sensor. Possibly the one you got was bad to begin with.

Maybe but might have to wait till i get my next check to find out for sure
Im running alittle low on that leafy green paper stuff
Ok?

Correct, or reading the fuel trim setting. The long term should be no more than 5% + or -

So far long an short term have both read 0%

The short term should be fluctuating. If they are both consistantly zero then your ECU is running on factory programming. When you get a chance try to graph the 02 sensor 1 on bank one and two. It should be a line that jumps up, levels off, jumps down to then levels off, jumps up , and so on

Ok ill ad that to my list
Is that more likely to happen after the motor warms up?