Contour Enthusiasts Group Archives Forums Modifications 3.0L Duratec The 3L is up and running!

Yeah, that's why a lot of my questions come to you

What sucks is we took the UIM off and inspected the gaskets, especially right where the carb cleaner was affecting idle, and everything looks to be perfectly fine. The gaskets look fine and there was a little line on top of the LIM all the way around the suspect area which looks like it sealed good. We replaced the UIM gaskets anyways since I had a spare set laying around (the ones we originally used were also new BTW), and the idle got slightly better, but the problem is still there and that same area still reacts to carb cleaner slightly. Has anyone else had problems with getting the UIM to seal properly?

Also, is there any way in the SCT PRP to add more columns to the base fuel and knock tables? The RPMs only go in increments of 1000 on the fuel table and I want to at least have it go by 500 RPMs.

[Edit]
I forgot to mention about the IMRC spark adder. When the IMRC is turned off in the software, all of the IMRC specific tables disappear with it, so I'm guessing that there's no ~10* of timing being added anymore at IMRC point. I even turned it back on to zero them all out and turned it back off to be safe, but I still feel that jump in power at ~3000 RPM. I guess it's time to play with fuel and timing once more

You don't need to add more columns to your tables, you just need to change the axes of the colums so that you can change the increments.

below the actual tables in each section are little tables of columns that show the normalizers for each axis.
Such as this example for the maf tables:

ynorm_maf_01(stock) xnorm_maf_01(stock)
TP Row # RPM Col #
1023.9844 9 16383.75 9
750 9 7000 9
500 8 4000 7
300 6 3000 6
0 0 1800 2
0 0 600 0
0 0 0 0
0 0


The first column is ynorm_maf and the second is xnorm_maf.

the Y axis is the value in Throttleposition counts for the stock MAF at each row. The zeros are just blanks that can be used if you want to specify more of the rows.
The top row number is 9 meaning there will be 10 rows in the table the bottom being 0. That means that the number of row s will be 10, with the range of TP going from 0 to 750. THe 6 row will be 300, 8th 500, and 9th 750. Well if you look at it, that means that from rows 0-6 you have a TP value of 0-300, meaning that the computer will automatically assign a value for rows 1,2,3,4,5 in equal spacing.
Like this:
0 - 0
50 - 1
100 - 2
150 - 3
200 - 4
250 - 5
300 - 6

And so on. If you wish, you can change the top end of the scale from 750 to say 900 at row 9 and specify the 0 position as zero. The computer would assign all values in between evenly. IF you felt the need to specify exact areas of TP then you can do as above, up to and including using every cell to specify a rang of TP.

For the RPM range it is the same way.
Say you want extra precision in your table from 3200-3800 rpm so you can tune that area in better detail. It would look like this:
0 - 0
0 - 600
2 - 1800
3 - 3200
4 - 3400
5 - 3550
6 - 3700
7 - 3900
9 - 7000
9 - 16383.75

The bottom 0 - 0 and 16383.75 - 9 is automatic and defines the min/max values for the table. Anything you input falls in between. By assigning 7000rpm the value of the 9th column you end the range there rather than at 16383rpm. Anything above 7000 rpm will use the same values as you input into the cells below the 7000 rpm range at the respective TP values.

So, if you don't car and want even spacing assigned by the computer you do the following
0 - 0
....(meaning other cells filled with 0 - 0)
0 - 600
9 - 7000
9 - 16383.75
Now the computer will assign the rpm to the ten columns evenly from the two values in even increments, 640 rpm each so that column 0 - 640, 1 - 1280, 2 - 1920, ... 8 - 6360, 9 - 7000.


Okay, hope this is clear enough on how to modify the axes for ANY of the tables in your PRP setup.
I advise you to NOT adjust the ranges unless you have something you want to do. For example fuel and or timing control of the IMRC point, or changing the RPM range of the actual IMRC point. You can specfiy added areas of rpm and load for the IMRC opening/closing points to take care of certain problems, or to smooth transitions out.
Also, if your rpm range is raised and you feel you need to alter something at rpms above 7000 rpm, in such a way that the values used in the cells below 7000 rpm doesn't apply, then you would make your upper limit the rpm where you want to change that thing, such as 7200 rpm; say for increased fuel at the top of the range for added resistance to detonation.

Clear? Clear as Mud I'll bet. Well don't anyone go PM'ing me over this. IF you have questions post them here where others who have time and experience can elaborate on this stuff and when I get time I'll come back on and help.
With the frequency of people buying the PRP going up, this kind of information will become more usefull, and when people understand that tuning isn't Voodoo or Rocket science then maybe there will be less people paying through the nose when they really want to do the detail work themselves.
Good luck.

Actually what you said makes perfect sense to me (I think). But just to make sure I get it exactly, I want to go through an example using the fuel table. Let's just use:

ynorm_fuel_base_table
1.9999695 7.000
0.8500061 7.000
0.1499939 0.000
0.0000000 0.000
0.0000000 0.000
0.0000000 0.000

and xnorm_fuel_16
16383.750 9.000
7500.000 9.000
6500.000 8.000
4000.000 3.000
1000.000 0.000
0.000 0.000

If I understand correctly, if my car is at a load of .8500061 and an RPM of 6500, the AFR value should be whatever is in row 7 column 8 of the base_fuel_table. What I don't understand is which normalizer table is used and when. What I'm talking about are xnorm_fuel_16, xnorm_fuel 18, ynorm_fuel_15, and ynorm_fuel_base_table. The info in Advantage doesnt really tell me why there are all of these different tables instead of just one ynorm and one xnorm.

I still can't figure out why my car occasionally stumbles (sudden power drop spike) during acceleration under partial throttle. I doubt it's because of the vacuum leak because it seems to happen right at the same RPMs every time (right around 2300 RPMs and again around 2800 RPMs. I don't think it could be a misfire either for the same reason, although it does feel like a misfire. What do you suggest I start playing with on my PRP to try to cure this?

As for the IMRC, I gutted it all out of the LIM, and turned it off in the PRP software, so there's no more tables for controlling anything having to do with IMRC. I did add fuel and spark advance below 3000 RPM (~12-14* more advance added than above 3000 RPM) in the base knock table (and maxed out the maximum allowed spark table so I don't have to keep changing it also) and I still feel a jump in power right at 3000 RPM. I'm guessing there's something else I need to change that I've overlooked, but I haven't been able to find it yet. BTW, if it makes any difference, the car does run a lot smoother, albeit less powerful, when the A/C is on. Even the idle is almost always smooth and right where it should be when the A/C is on.

I also tried to raise my rev limiter to 7500, but that didn't work either. I raised several different values having to do with the rev limiter but it still gets stopped at 6750 RPMs

The only other problem I'm having is the car is occasionally "jerky" when coasting down with my foot off the gas.

Okay, all of those things are fixable I think.

Lets start with the Max Allowed table:
No NO and HELL no on raising it up all the way.
Between me and you....the max allowed table is kind of the central table that all the spark timing hovers around.
All of the other tables (except for a one or two) are used in conjunction with the max allowed table. ACT and ECT tables are just multipliers of the max allowed spark value in a particular cell.
So if at 0.50 load and 3000 rpm you have a value of about 20* max allowed advance, the ACT at loads similar to that may introduce an 10% increase in spark at that point based on cool temps, or th ECT may also do the same. Then there is the IMRC which will add more spark at certain loads above the opening point. It ALSO works in conjuction with the max spark allowed table as a base table.

When I was planning out my Max allowed table, I started with stock, increased the load range on the Axes since I was forced induction to about .99 and then put limitations that I felt would be safe in the loads above 0.6 to 0.7 Then I let the computer actually add any timing to those maximum values based on ACT ECT and as long as it didn't go above my maximum desired timing. For example, I didin't want to go above 23* on a cool day boosting 7-8psi, so I did a rough calculation on the timing advance for cells above 0.85 at the appropriate RPM to determine the maximum it could hit, then adjusted the max allowed table accordingly.

As far as the MBT spark tables, they do absolutely NOTHING for advance but after I worked out the timing tables to my liking I adjusted them downward by about the same percentages to keep the computers torque calculations in-line.

Most importantly, I used a OBD II scanner, AND The XCAL2 to datalog while driving around to see what the values and loads were at cruise, idle, and full throttle. After about 5 days I had a good tune and felt comfortable to raise the boost after confirming with the wideband that the AFR was as expected.

So leave everything close to stock...then remove the IMRC, then test drive. If the stuttering goes away, then you know you had too much timing.
Don't rely on the knock sensor tables to appropriately pull back timing as protection. They don't work all that good and you will be losing power in some cases before you actually experience predetonation.

Leave the stock settings mostly alone until you get it driving fine with no codes, doing only what is necessary to correct for intake system changes and other mods. Then change only one major variable at a time, such as increasing the maximum timing at max load, all by 10%, or changing only the last 1000 rpm by some amount...you know what I mean? Address specific problems first. Have an overall plan of attack on what you want out of your car.
or change the priority order once you know what you want.

I have found that a timing change of just 2* made the difference between a rough sounding engine at high rpm windout to a smooth sounding engine. I mean at 6000 rpm and spinning toward 7000 rpm, you can hear little things that are hard to describe. If you go slowly and increase till you get these audible changes, then pull back a little, you can get a 90% solution before you ever hit the dyno.
You can see, I was able to roll into the dyno in Montgomery and with NO required tuning changes after the first run. I was able to raise the power to the wheels from about 310 up to 355 in 3 or 4 dyno runs just by turning up the boost....at least until the soft wastegate spring began opening on its own. This is the power of the EEC-V adjustable PCM, getting the settings basically right and letting the computer adjust as it needs to, to meet those settings.

Also, don't underestimate the power of a bad set of ingition components to introduce misfires and stuttering.
At 40K miles on my car I once spent over $500 "modding things" because I felt the stuttering must have been caused by a mod I did on the 3L. 3 months later with a gradually worsening problem, I finally gave up and bought a new pair of plug wires to replace the "visually apparently New" stock wires, and the problem was gone.
It was my greatest shame of misdiagnosis I've done in many many years. However it taught me a lesson and I always go back to basics before I suspect something complicated when diagnosing a problem.

So fix what needs to be fixed first; start with stock and go incrementally till everything runs right, THEN optimize with a controlled set of variables, never changing more than once component at a time if possible to limit the possible problems.

Sorry for the length....there's different points in different paragraphs.