Tune or something else?

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Falcon_LS

Falcon_LS

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My '01 Grand Marquis is tuned, part of which involved increasing transmission line pressure. I've been told the line pressure is the same across the board, except it has been increased from 33 PSI to 100 PSI at WOT. For anyone in the know, this is what the tuner's sent me:

Code:
Trans Tv Pressure 12



SGA2 - 1



5.000 0.000 12.000 23.000 23.000 25.000 26.000 28.000 100.000 100.000



5.000 0.000 12.000 23.000 23.000 25.000 26.000 28.000 100.000 100.000



5.000 0.000 12.000 23.000 23.000 25.000 26.000 28.000 100.000 100.000



5.000 0.000 12.000 23.000 23.000 25.000 26.000 28.000 100.000 100.000



5.000 0.000 12.000 23.000 23.000 25.000 26.000 28.000 100.000 100.000



5.000 0.000 12.000 23.000 23.000 25.000 26.000 28.000 100.000 100.000



5.000 0.000 12.000 23.000 23.000 25.000 26.000 28.000 100.000 100.000



-20.000 -7.000 12.000 23.000 23.000 25.000 26.000 28.000 100.000 100.000



-20.000 -7.000 12.000 23.000 23.000 25.000 26.000 28.000 100.000 100.000



-20.000 -7.000 12.000 23.000 23.000 25.000 26.000 28.000 100.000 100.000







SGA2 - 2



--- --- --- --- --- --- --- --- 33.000 33.000



--- --- --- --- --- --- --- --- 33.000 33.000



--- --- --- --- --- --- --- --- 33.000 33.000



--- --- --- --- --- --- --- --- 33.000 33.000



--- --- --- --- --- --- --- --- 33.000 33.000



--- --- --- --- --- --- --- --- 33.000 33.000



--- --- --- --- --- --- --- --- 33.000 33.000



--- --- --- --- --- --- --- --- 33.000 33.000



--- --- --- --- --- --- --- --- 33.000 33.000



--- --- --- --- --- --- --- --- 33.000 33.000







Trans Tv Pressure 23



SGA2 - 1



-22.000 -22.000 -22.000 -15.000 0.000 6.000 8.000 15.000 100.000 100.000



-22.000 -22.000 -22.000 -15.000 0.000 6.000 8.000 15.000 100.000 100.000



-22.000 -22.000 -22.000 -15.000 0.000 6.000 8.000 15.000 100.000 100.000



-22.000 -22.000 -22.000 -15.000 0.000 6.000 8.000 15.000 100.000 100.000



-22.000 -22.000 -22.000 0.000 6.000 6.000 8.000 15.000 100.000 100.000



-22.000 -22.000 -5.000 0.000 6.000 6.000 8.000 15.000 100.000 100.000



-22.000 -8.000 -5.000 0.000 6.000 6.000 8.000 15.000 100.000 100.000



0.000 -8.000 -5.000 0.000 6.000 6.000 8.000 15.000 100.000 100.000



0.000 -8.000 -5.000 0.000 6.000 6.000 8.000 15.000 100.000 100.000



0.000 -8.000 -5.000 0.000 6.000 6.000 8.000 15.000 100.000 100.000







SGA2 - 2



--- --- --- --- --- --- --- --- 22.000 22.000



--- --- --- --- --- --- --- --- 22.000 22.000



--- --- --- --- --- --- --- --- 22.000 22.000



--- --- --- --- --- --- --- --- 22.000 22.000



--- --- --- --- --- --- --- --- 22.000 22.000



--- --- --- --- --- --- --- --- 22.000 22.000



--- --- --- --- --- --- --- --- 22.000 22.000



--- --- --- --- --- --- --- --- 22.000 22.000



--- --- --- --- --- --- --- --- 22.000 22.000



--- --- --- --- --- --- --- --- 22.000 22.000


Trans Tv Pressure 12 is shift pressure from first to second, Trans Tv Pressure 23 is shift pressure from second to third. The first batch of numbers is the tune, the second batch underneath with the "---" is stock. I've been told "---" represents no change. I'm not sure what the "-" represents, because negative pressure would be a vacuum if you know what I mean. SGA2 is my PCM code.

To be honest, my pressure regulator is buzzing as I drive, so I am pretty sure some changes must have been made to line pressure other than WOT.

I use Motorcraft or Kendall branded Mercon V and always drain the torque converter so I get at least 14 quarts or so of fluid at each ATF change (25,000 miles). I use a Motorcraft FT-105 filter and also reset the PCM after I change the ATF.

If I reset the PCM, the car is as smooth as butter. As soon as it relearns its cycle, the car drives like it's on a leash. I find this very strange, because I was under the impression that the adaptive learning function would be disabled. For example sake, it's like a manual transmission that's stuck in gear and the RPMs won't go down when you release the gas. I took it up to 40 MPH and touched the brakes just enough to illuminate the brake lights, and the RPMs does not drop...stays at roughly 1,300 rpm. So I replaced the TCC solenoid to no avail. It still does the same thing.

Here's where it gets worse. Sometimes as I'm coming to a stop, I feel a thump and the RPMs go down - usually to 4xx RPM and back up to 600 RPM (idle speed raised to 600 in gear and 800 in park/neutral). If it goes lower to 1XX RPM, the engine stalls.

I have a feeling this is the tune, so I've contacted Lonnie at Blue Oval Chips, considering his mastery with mail tunes. But I'm still not ruling out the possibility of a mechanical issue. Any ideas?
 
A little background:
I've had 2 CV's tuned by Lonnie, my 2002 sometimes exhibited a flashing OD indicating 2-3 shift out of range. This was not really a big deal, what it was telling me was that the unit had enough miles/wear to sometimes slip slightly. I could never feel it, but the PCM read the slippage as out of range. Just an example where sometimes the tune (and associated re-program of the EPC solenoid) will uncover internal wear that is masked by the factory program. This can happen with a seemingly "normal" transmission.
The EPC solenoid in your 4R70W is what controls the overall line pressure from the pump. However there is also a shift solenoid pack (1-2, 2-3) that controls timing of the up/downshifts between these clutchpacks as well as having input into OD band application.
That shift solenoid pack sometimes can get some debris into the fine mesh screens that insert into the valve body to cause extended up/downshifts.
What I had done before the tune was to replace a series of components that are wear items since I knew that the tune would recalibrate (increase) the EPC line pressure. Among these parts were all accumulators, OD servo, and all shift/tcc/EPC solenoids. I had also done the j-mod to ensure that the internal fil/exhaust fluid volume was increased to compliment the increased line pressure. This was on a transmission with about 140K on it, well maintained. Sounds like a lot of parts but other than that occasional 2-3 anomoly, the transmission(combined with engine mods) shifted hard enough to chirp tires at both 1-2 and 2-3 shifts. However, the characteristics of the shift patterns were changed even with slight throttle applications - not bad, just different. This included a slightly longer "hang time" for downshifts.
For your transmssion, I suspect that the EPC pressure may indeed need to be throttled down a bit, but I think also that perhaps Lonnie may want to double check the PCM settings for engine management as well. The 4xx rpm is too low, obviously. The other wild card is that you may have a masked issue with shift solenoids and/or one of the shift accumulators/OD servo that is being incovered with the reduced shift overlap times. When people install the j-mod for example, they get all excited about how hard the transmssion shifts, yet the internal line pressure is unchanged. What they are feeling is the greatly reduced overlap between clutchpack applications and disengagements, just faster shifting. If the internals are not up to snuff, strange things can happen with the install of a tune.
The buzzing you hear from the EPC is a good clue, it may not be balancing pressure correctly and can be the cause of the erratic shifting. Too high a pressure is usually harsh shift patterns, too low is late/soft shifts that overheat the clutch facings. If I had a choice of what I would do, I would consider replacing the EPC solenoid - valve body has to be dropped to do this so new separator plate gaskets (cheap) are a must. And I always use a torque wrench to tighten the VB bolts, easy to warp it.
Hope some of this helps. Go on cvnet and look up a tech write-up I did (Blue95) on OD servo replacement, it includes info/pics of all this stuff.
 
Sounds almost like the converter isnt unlocking.
I had a BOC tune. I wasnt happy with it and he wasnt willing to make changes, so I went to Marty at Mo's Speed Shop and they set me up with a tune I am happy with.
 
Thanks for the input!
thumbsup2.gif


Mud, I've found your article and will be tearing into the transmission in about a week's time. With the valve body out, I plan on doing the J-Mod as well and the OD spring upgrade. I'm a bit worried about doing the J-Mod though, in case I screw up. Trying to find a step by step article.
 
The write up on TCCOA about the J-Mod is one of the best out there. Just be really careful drilling the plate, if you mess up, you need to get a new valve body from FoMoCo.
 
No need to get that, I'm not sure its right for your Marquis anyway. I've seen the care you put into your vehicles, you will be fine doing the j-mod yourself.
There is a complete how-to in the cvnet body of knowledge under Powertains, about second from the bottom, authored by drock.
 
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