WS6 GreeN

OK, I was at the track recently and after making a few passes I reviewed my logs. Right now, I am running in OL and I've tried this in SD and also with the MAF enabled. My LC-1 reads nice and rich at 12.5-12.8:1 but at around 5300 rpms, the air/fuel shoots up to 21.3 and I have no clue why. It doesn't feel like its losing a lot of power or dropping off. I'm not real sure what to think of this. I thought if the wideband sensor was going out, it would cause a code. It's strange that it's doing it on every WOT run and RIGHT at 5300 rpms. There is no knock above those rpms either. I'm kinda at a loss here. Any help is greatly appreciated. I don't know where to start. The plugs are gapped at .053 I think and the plugs and wires are new. I'm making 400 rwhp with bolt-ons and a cam.

SSpdDmon

iTrader: (10)

Maybe not getting enough power above 5300rpms???

RedHardSupra

iTrader: (1)

what injectors you got?

Sean Collins

thats not near enough power to max out a set of 28's.id suspect fuel pump issues. Check rail pressure with it during a pull either that or its lossing ignition.

Edit:

On second thought what type of valve trian you running ? could be valve float.

RedHardSupra

iTrader: (1)

yea it is, i hit 109% idc on 26.4s while putting down about 360rwhp

Sean Collins

Funny i get 450whp out of them (with stick shift cars)all the time 28's that is. Funny thing about PW calculators alot of them don't take into consideration that Sequential firing sequences have double the firing time of batch systems. Check to make sure the formulas you used to calculate DC are based on sequential injection.Although a big stall auto car with slippery converter might be pushing well over 500hp at the flywheel so its beliveable.

WS6 GreeN

I'm using the stock injectors and the car's an '02. Thanks for the input so far. Someone told me it couldn't be an ignition problem because it wouldn't show up as extremely lean due to the extra unburned fuel as well. It just goes straight to 21.3 with ONE cell of 16 before shooting up that high. But there is no knock. I don't understand. I may get some dyno time and a gauge to measure the pressure at the rail.

Sean Collins

I have seen one missfiring cylinde rpush the AFR to as high as 18.0:1 so if you had sevral it could peg the meter.

WS6 GreeN

So how do I track this misfiring cylinder? I've got a log set up for misfires but what should I look for? What is normal for my cam? If one cylinder is showing twice as many as the rest is that a good sign? Should I decrease the gap on the spark plugs? Replace coil packs? Wires? Fuel pump? lol

jimmyblue

iTrader: (11)

Fuel filter?

What is injector pulse width doing when this happens?
Have you taken and converted this to injector duty?
Or maybe your tool will display it straight, I recall this
as a "sensor" item in HPTuners I think.

Putting a pressure gauge to the rail for a pull, would
answer a lot of questions.

WS6 GreeN

Jimmy, I'll take a look at the IPW when I get home. From what I remember, it wasn't doing anything strange. I also forgot to mention another important piece of info about all of this. Sometimes while cruising, the car whill just decide to go lean to 16:1 or a little leaner sometimes. If I rev the car up a few times, it will return to normal. Fuel filter's an easy change so I may do that. If the coil pack or plug is not firing, would that show a false lean condition? Someone clarify that for me. Thanks!

RedHardSupra

iTrader: (1)

how about a leak? do your stock O2s hold steady at WOT, or do they have spikes toward the lean side occasionally?

dynocar

If your WB is going that lean, monitor both factory O2s, if both show a lean condition, you have a fuel system problem, if only one shows lean, you have it narrowed down to four cylinders on one bank, if none show lean, it's your WB acting up.