Unsticking IMRC's by hand?

try this....

run to an autozone and see if they have a fuel pressure tester in their "loan a tool" program.

I'm wondering if the one your using now isn't working right.

at 100% duty cycle if your regulator is good should be well in excess of 40PSI.

I hate to have to just "throw parts" at the car, but I wonder if your regulator isn't bad..(just a far fetched guess tho)

my luck is always worst case scenario..
I wonder if your luck might be better and you have a bad regulator..

THAT would be a first that I'd heard of though.

just thinking outloud here
if the regulator wasn't working it could be running yoru fuel system in "Full return" and pumping ALL the fuel back to the tank..
the pump is running at 100 D/C trying to "keep up".

See if you have about 35-40PSI at idle with the vacuum hose connected to the regulator, then unplug the vacuum line and the pressure "SHOULD go up into the 43-45 range.

give that a shot..and keep us posted
 
weird...
I dont see 100% duty cycle on teh pump.
The car is still knocking though...definately

In the Xcal.. go into the spark settings and pull 2 degree's out from 0-2000 and 2 degrees out from 2000-4000RPM

dont change anything else..
 
Also, if I may add.....

when you make a datalog, add in STFT1 and STFT2 and always log "vehicle acceleration rate" along with vehicle speed.
 
On the duty cycle: I had seen a post on the old SCT forums by a guy from SCT that the fuel pump is at 100% at either 1.0 or .5, depending on which version of live link you have or something like that, and since the log for mine maxes out at .5 it makes sense that .5 is probably the max in this case. Or I could be wrong... but it just seems weird that it would stop right at .5 then never go over it if it wasn't maxing out.

But anyways, I reflashed again and pulled an extra 2 degrees out from 0-4000, and left the rest the way it was. Did another datalog, here's a link that hopefully works for you: http://www.filefactory.com/file/af2aaeg/n/2-23-09_WOT_csv

Only thing worth noting on this log is that the tires spun a little off the line, and it was done by the on device datalogging instead of pass through datalogging to a laptop like all the other ones have been done. Other than that though, it's all the same.
 
Kraze, I cant download that file...haha

can you email it to tomdouglas@hotmail.com

Something with our firewall at work isn't connecting to these free upload sites..(weird)
 
Lol done. I'll just email them to you right off the bat when I have new ones and upload them for everyone else lol.
 
looks like it's still knocking...

I'd say pull 2 more degree's across the RPM range.
0-2000K -2 degrees 2000-4000L -2 degree's 4000-8000 -2 degree's
 
Kraze, I noticed in your latest datalog file you lost Fuel Pump Duty Cycle.. can you add that back? (lol)

Also, you have 3 different spark sections.
take out borderline and MBT spark and put fuel pump duty cycle back in.

cool?
 
I had seen a post on the old SCT forums by a guy from SCT that the fuel pump is at 100% at either 1.0 or .5, depending on which version of live link you have or something like that, and since the log for mine maxes out at .5 it makes sense that .5 is probably the max in this case. Or I could be wrong....

could be either you right or wrong.. not sure.

what version of Livelink are you using?

I saw that post Ryan made on SCT about that persons version being old.
he had a version 2sumthing...

I've only got livelink3 and livelink4.
 
And finally, we have a run without any knock sensor activity at all! Well, negative knock sensor activity at least lol. Here's the file: http://www.mediafire.com/?sharekey=e2fe112b800ba28ded24a2875c7fa58ee04e75f6e8ebb871

And I'll email you the file also XLR.

This was with an extra 2 degrees pulled out from the whole range, for a grand total being: -6 at 0-4000 rpms and -5 at 4000-8000. This is still 6% richer too. Seems kinda excessive just to get it to stop knocking huh? Should I keep these settings for now?

And for some reason the fuel pump duty cycle didn't want to log, along with a couple other things, so I'll have to take a look into that and hopefully get that working again. BUT.. I did some more researching and .5 is the max for many PCM's. However, and I'm not sure on this one, but since our cars have a return-style fuel system, I guess it's normal for the fuel pumps to reach max at high loads since the excess fuel is just being returned anyways? There's not too much info on that though, so if anyone knows more about it then feel free to chime in.

Also something weird about the log. According to it, the car shifted from 1st to 2nd at 45 mph but at 6100 rpm's. Now I know for a fact that if I'm at WOT the car doesn't shift into 2nd until about 55.. what's up with the log then?
 
It's not unreasonable... if Torrie tossed a bunch of spark at your tune and your car can't handle it then you need to pull some out... Put it back to stock and see if it knocks.
 
Very true. I just looked at XLR's 1/8 mile run again, and even with all that timing pulled out on my car I still have more spark than him throughout most of the RPM range. However, he's running a quite a bit more lean commanded A/F ratio, and his load and MAF voltage is a lot better than mine.

Do you have any datalogs from your car that you could upload for me to take a look at kid?
 
Hey, am I seeing this right?
the car didn't knock this time?

from what it looks like the KS did go into positive numbers rather than dumping timing like the last runs.


At the beginning of the runs, it still looks to be spinning the tires?
With that said.. does your car have traction control?
Wondering about the big dip in spark at teh beginning, but it's not really an "issue" per sey.

So, from between 3900 and 5900 you actually getting some spark chunked back IN by the Knock Sensors
I would go back in, and add 1 degree between 4K and 6K.

looks as if we're actually "getting a handle on this".

I think we're very close to nailing down the spark, or detonation..
 
Seems kinda excessive just to get it to stop knocking huh? Should I keep these settings for now?
?


I would make the small changes I mentioned above, and I think KK nailed your question fairly well.

Without knowing how much spark was added, there's no way to determine if what you have taken out is considered "excessive".
 
Also something weird about the log. According to it, the car shifted from 1st to 2nd at 45 mph but at 6100 rpm's. Now I know for a fact that if I'm at WOT the car doesn't shift into 2nd until about 55.. what's up with the log then?

your peak RPM is indeed at 45MPH but .72 seconds later the car is in 2nd at 51MPH and it's accelerating at 5.2MPH per second.

I would trust the datalog for the information it's giving you, over the cars speedometer.
 
Very true. I just looked at XLR's 1/8 mile run again,

That pass was in July in the texas heat, absolute worst case scenario for running a car at the track.

My tune has changed 4-5 times since those passes but I've made no significant changes to timing.

I made some initial changes to timing early on in the tune (almost a year ago) and haven't made any changes since.

I need to get back to the track while the air is still good and get some recent datalogs.

My car went 9.97 on that pass in July and it went 9.79 about a month ago.

...dont ask why I didn't datalog my recent passes
{embarrassed n00b look)
 
If might be able to grab a few logs here soon.... I haven't driven my car since fall... it's about time to roll it out of the garage.
 
Alright I'll go back and add a degree to that range after class today and see what I come up with.

And it's just weird that it would say I'm shifting into 2nd at 45 when all the other logs say it's happening at about 54, and that's what the speedometer in the car is saying to. But all the other data seems right so I guess I won't worry about it.

What do you guys think about my fuel pump duty cycle theory though?

Lol and don't forget to log your next pass XLR!
 
And for some reason the fuel pump duty cycle didn't want to log, along with a couple other things, so I'll have to take a look into that and hopefully get that working again. BUT.. I did some more researching and .5 is the max for many PCM's. However, and I'm not sure on this one, but since our cars have a return-style fuel system, I guess it's normal for the fuel pumps to reach max at high loads since the excess fuel is just being returned anyways? There's not too much info on that though, so if anyone knows more about it then feel free to chime in.

i think your correct, and until I can find a datalog that says otherwise. I'm inclined to agree with you.

I have another buddies log file and his "reaches" .5 and doesnt go any higher, roughly AT the same time yours does.. but his doesnt "flat line" like yours does
 
Does he also have a Mark VIII? If so, would you mind uploading the log or sending it to me? I always like looking at other logs to see how my car stacks up to the others.
 
it's a 97 LSC
shoot me your email and I'll send it over.. no problem
 
Alright, added back 1 degree of spark to the 4000 on up range and came up with this: http://www.megaupload.com/?d=HUXCHN75

It looks awesome! ...until you get to 3rd gear. I need a damn PRP :( So what steps do you take now? The knock sensors don't even touch the timing in the first two gears.. maybe I'm just going to have to accept that it will pull some timing in 3rd for now until I get everything figured out?
 
. I need a damn PRP So what steps do you take now? ?

yea it looked like it knocked, the the fuel pump duty cycle was pegged.

I agree, your at the edge of the cliff... you probably need the PRP software.

the spark adders in the xcal have no where near the adjustability found on the software.

With your issue your working with "global"/"blanket" adders.

With the software you can change individual load points, along WITH RPM ranges..that gives you alot more adjustability.

I'd say at this point, pull some spark out of the top.. leave the rest the way it is..and maybe chunk that 4% fuel you left out.. I suggested a 10% increase and I think you only did 6%?

Bump it to 10... before you pull any timing.. if it still knocks..THEN pull some timing.
 

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