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PE nuts

Setting TM back to stock had no effect.

Here's what happened on my 100% stock file:

06302008_160907 from sabrewings -- Scan Depot dot net

Question. I've just been doing partial writes. When I loaded my stock file back, I didn't do anything about the fuel trims either. That shouldn't really make a difference with PE should it?

What could be causing knock in PE like this??? Something mechanical?
 


Just a thought... Could this be a bad gas issue? I don't use much fuel. A whole tank will last me three weeks since I work very close to where I live. I recently just refilled from the same gas station (an Exxon) I always gas at. So, if there was something wrong with their 93 I'd be running that fuel for a while.

I've got a 6 hour drive coming up so I'll be able to clear this tank pretty quickly and get a new tank in Memphis. Following this train of thought (as I was just resting my head on my desk), I remember my friend commenting that my spark advance was awfully low. Could I be running on my bad_fuel_spark table? If my PCM thinks I have bad gas, I probably do...
 
I always copy my high octane spark table to my low octane just so the timing stays where i put it. imo bad gas could not cause that much kr. this is not directed twards you or anyone on here but why does everyone always talk about bad gas? what is bad gas? Like how is it different from regular gas? I think gas now a days has a pretty high q/a control on it. just my thoghts. i'v never had bad gas to my knowledge. good thinking though...it's probably the smallest that you and everybody else have over looked that is causing all of this lol.:p
 
Bad gas doesn't have the octane rating it claims, or it has some sort of contaminant limiting its power. Some bad gas you car can barely run on, other gas causes knock (also known as "hot" gas). Put simply, I can think of no reason mechanically why it should knock like this with the settings all returned to stock.
 
Bio248 said:
wideband. you need one.
Click to expand...

Why? Obviously I have issues beyond tuning because a completely stock file and its still going berserk and it didn't used to do this. I have a mechanical issue and a wideband is a waste of money in trying to find it.
 


Here's a scan to look at. I went out on my stock file again, a complete write instead of just partial. Still seeing the same issues, but this is a nice long scan with all the values. Maybe someone will see something. One WOT run, a few 60-65% TPS runs, and a good bit of cruising.

06302008_220607 from sabrewings -- Scan Depot dot net

I added some fuel treatment stuff (couple bottles) since it was at the onbase shoppette for cheap. Hopefully that'll keep it good enough to run home on. I'm also topping off at a Chevron this time before I leave.
 
Do you have an old scan when it was not messed up?
What did you install when this started?
Keep the stock bin in and rescan the car. Compare it to an old scan if you have one.
lets find out why this is happening before we start chasing our tails in a tune.

webracin
 
Holy ****. Do I have to run this freaking rich??? I found this scan. I chopped out the part I want you to look at...

possiblesolutionpe from sabrewings -- Scan Depot dot net

Note how the AFR keeps dropping and O2s are climbing... the, at about an AFR of 10.4 it starts dropping off and the AFR finally hits about 9 with O2s in the nearly 960 range. I have to run THAT freaking rich?!?!

Edit: Or look at this one. Same thing happening, but it gets down to nearly 8:1 and my O2s are up over 960 and the knock is practically cleared you can tell by the rate at which it's recovering. I'm so excited I can hardly contain myself. I had no idea I had to be that rich, but whatever tune I was on at that time was working.

http://www.scandepot.net/viewscan.php?pk=5156
 
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my bad, didnt read into it that much.

why the crap are you knocking at 2000+ rpm?! your mod list doesnt reflect anyting that could be screwed up since your tune has good fuel trims. im lost.

i havent had much experience with tuning as i dont have any of the tuners/software, but something is wrong that youre knocking down low so much. that cannot be a tuning issue. when did you replace your o2 sensor last? fresh plugs? new wires? all the tune up stuff done?
 


Bio248 said:
when did you replace your o2 sensor last?
Click to expand...

Never. Only got 67k miles.

Bio248 said:
fresh plugs?
Click to expand...

Coming soon.

Bio248 said:
New wires?
Click to expand...

See above

Bio248 said:
all the tune up stuff done?
Click to expand...

Fuel filter not long ago, air filter is good, etc.

Though, I may have found my problem, crazy as it seems. See last post of previous page.

Also, according to this diagram, my injectors are breaking the laws of physics:

post-385-1192633064.jpg


You can clearly see in one of my scans that at 5160.5 RPM my IPW is 25.28ms. My injectors are going practically static with the AFR the PCM is commanding, but its fixing the knock. I may see if I can tweak it as I don't think that low an AFR is required. Just that the RPM vs Time table was driving it so low. At least that's my theory...

Interesting development to say the least. It may be my plugs or O2 sensor are on the way out...
 
you should never ever max your injectors with your amount of mods. is it possible that one of your injectors is fubar'd or your fuel rail/line is kinked in any way?

i didnt really look, but how does your timing look? are you commanding something like 30* WOT?
 
I don't believe I have a fueling issue. I have no misfires recorded, and as the PCM commands a particular AFR the O2 sensor is showing its achieving that AFR. I'm just wondering why I need such high O2s to not knock.

I'm going to do some maintenance at home. I'm about to order PRJ wires, AL605 plugs, and a new O2 sensor. If that doesn't fix it, I'll do a fuel pressure test. Depending on the results from that, it might be time for new injectors (since I was planning on swapping to 04-05 L67 or maybe L32 injectors anyway before I start moving towards more mods so I always have the headroom).
 
Someone on the DHP forum brought up that it might be TM showing up. Does TM appear then go away at the standard KR recovery rate? Does it appear right as you enter PE?

I left a lot of my TM settings alone. I want my tranny to last, but I did adjust it so that it can't turn off injectors.
 


I have always been told that TM will appear to be knock, but its not actually. It tells the PC there is knock present so that it can control spark and fuel. May want to see what Overkill has to say.

webracin
 
Bio248 said:
torque management does not create knock. it's a myth.
Click to expand...

We know it doesn't create knock, but there's strong evidence to support that it shows up as knock (since the "KR" value should be renamed "SR" or spark retard).

I'm very interested in what Will would say.
 
Just to clarify something. KR could be a few things...TM will show up as KR in the PCM and here's why. Anytime that timing is pulled it shows up as KR. yup, it's as simple as that.

Now, onto the problem. I honestly think that this deal is running way to rich for a n/a. If you're running too much fuel, some can be left over in the cylinder, and once fresh air/fuel hits it it could be flubbing up your AFR and your timing. It probably is knocking from all the fuel it's getting.

Some suggestions I'd start with.

Put the VE back to stock
Put timing back to stock
Fueling back to stock
Raise all of your TM settings in your spark/fuel/transmissions tables...put them to the max.

I'd put a goal to start off with to get the O2's in the upper 800 range. Don't immediately go WOT, only go say maybe 60-70% throttle. That way if it starts to knock, you won't fubar your engine. Adjust your fueling by the MAF table, pull out 1% at a time in the Htz areas that you see the problem manifest. You probably want an AFR to start off with at maybe....12.6? I'm pretty inexperienced at tuning n/a engines right now, but I'm helping a local so I'll be more fluent soon I hope.

Just take this with a grain of salt, I may be totally off my rocker here as well. Just like everyone else, I'm just trying to help
 
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