o.k. guys I posted about my poor acceleration, it seems to be getting alot worse.
These are the tests that my dealer ran. Any ideas will help greatly.

EEC QK Test: Pass no codes
Relative Compression Test: Pass Equal Output
Power Balance Test: "" "" ""
Fuel Pressure Test: Pass Min 40 PSI
Mode 6 Data Aquisition: Pass No Misfire Data
DCL Display: Pass Idle Pid Data in Spec
Recorder Monitor Road Test: Pass Fuel Trim Data

this problem has only surfaced with in the last few weeks. I have owned the LS through summer time and even drive in Vegas part of the year. This issue is not because of the heat. Nor loss of power from use of the AC. I have about 86k. I have the KKM intake and custom 2.25 exhaust. This problem is really bugging me. I am wondering if it could be related to a bad cat?? (No jokes guys) I am fond of bad kitties if you know what I mean:D
I told the tech about the spark plugs but I don't think they checked them, unless thats what one of those tests does.....Seriously any ideas will greatly help. Thanks in advance....

did they do an O2 test for the cats?....is it getting hotter than normal?

If it was me Id look for a shop and let them do more than just a quik chk of the PCM/EMU.

they should be checking for exhaust restriction which can easily be done and alos EGR malfunction.

I just took it for a drive and Could this be related to my differential slipping?
I seem to be getting the power but feels like it's slipping then catching and taking off.

Also I am motor illiterate(sp) I can do custom fabricating but no motor work.....

EGR Malfunction????

And no it's running at normal temp. If this is mechanical those test won't find out what it is right? they only work for electrical problem right??

checking the spark plugs is not a simple task - so they normally simply replace them if they are going all the way into pulling a plug.

how about transmission? if the engine is running ok then the next step is to test the trannie.

have you done a coupl eof 0-60 and 1/4 mile tests to see if the car is close to where is should be on the numbers?

No, passes to see if the numbers are where they should be. I can do 1/8 runs here in San Diego on the weekends, but no 1/4. What if I dyno it? Would that give me some info to cross reference?

dyno is a great tool. make sure they read a/f while you're running it too.

Chart 8
Lack/Loss of Power
Note: Verify symptom is reported under normal driving conditions without excessive engine/vehicle load. Also, be aware of the engine rpm/speed limiting functions of the PCM.

Note: For applications with knock sensor, a lack of power may result when the vehicle is operated with a breakout box installed at the PCM. The KS circuits are not shielded in the breakout box, and KS signal noise may be noticed by the PCM. If this happens, spark timing will be retarded and a lack of power may result.



SYSTEM/COMPONENT REFERENCE (Section 5 Pinpoint Test unless noted)

Automatic Transmission Fluid

Throttle Linkage

Air cleaner element

Visual

Check the Following PIDS:
DPFEGR (if equipped) (hot idle value within 0.15V of KOEO value)
LONGFT1 / LONGFT2 (value between -20 and +20)
For 4.6L E/F Series, 5.4L 4V Navigator/Blackwood: IMTVF with both Key On Engine Off, and with transmission in PARK/NEUTRAL and engine rpm greater than 3000 rpm (PID should indicate NO in both situations).
DPFEGR PID value not within 0.15V of KOEO value:
GO to HE100
LONGFT1 / LONGFT2 value low (-):
Continue diagnosis.
Concentrate checks in areas that would cause the engine to run rich.
LONGFT1 / LONGFT2 value high (+):
Continue diagnosis. Concentrate checks in areas that would cause the engine to run lean.
IMTVF PID indicates YES:
GO to HU65

Fuel Delivery System
Natural Gas Applications:
GO to HB1
All others:
GO to HC1

Secondary Ignition
GO to JB1

Mass Air Flow (MAF) Sensor
GO to DC25

Exhaust System
GO to HF1

Base Engine
Engine System - General Information, Section 303-00 of the Workshop Manual

Automatic Transmission
Automatic Transaxle/Transmission, Section 307-01 of the Workshop Manual (Diagnosis by Symptom - Poor Performance)

Brake System (brake drag or binding)
Brake System - General Information, Section 206-00 of the Workshop Manual

Mustang only:
Check for lack of A/C cutoff under wide open throttle conditions.
Audible (listen for A/C clutch to disengage during a brief wide open throttle, then re-engage a few seconds after returning to idle). Follow Symptom Chart 21 if A/C does not cutoff.

F-150 Lightning (5.4 SC):
Supercharger bypass system
GO to KJ13

F-150 Lightning (5.4L SC):
Check high speed fuel pump secondary circuits
GO to KA70

Additional Testing
GO to Z1

Additional Checks:
NOTE: Some applications have a PID that will indicate whether the PCM is reducing torque (095E b0), and if so, why the torque is being reduced (095E b1-13).

Customer driving habits
Correct PCM vehicle identification (VID) block information (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM)
IMRC linkage (if equipped)
Clutch (M/T)
Charging System
Engine RPM/speed limiting functions of the PCM (look for incorrect high vehicle speed signal from ABS, VSS or OSS)
Visual. Appropriate Group of the Workshop Manual.

Any trouble shiftig? How does the clutch feel?

Any trouble shiftig? How does the clutch feel?

Shifting is smooth as usual, clutch has good solid pressure no grinding, It seems like something is slipping. As if I'm not having enough trouble with my car. I come home and see my Laptop screen has cracked!!!!!:mad:

Oh well I'm gonna go for a drive and see if I notice anything else to help you guys with more info.

I changed my air filter, had an extra one laying around. Checked my throttle cable, seems ok. O.k. around 40mph I am in 4th and try to accelerate, it shudders a bit then goes.... same in 2nd gear at 25mph same with 3rd @ 35mph. I am totally lost. I'm gonna make another appointment at the dealer, I am still under warranty. The oly time it doesn't do it is 2nd @ 40 mph, 3rd @ 60mph and 4th @ 80....( high RPMS)ne other ideas guys????

i had the same problem i searched and i think i need to replace my valve body and solenoid(tahts what i got from the resaech what my problem was)i bought my ls used so i'm pretty sure my pcm has beed reflashed. but it did it one day then the next but i laid off it a little and now its back to normal. but if it does it again i'm taking it to the dealership.

I swear...it sounds like your clutch is slipping. Can you smell it at all? At this point, I would take it to a shop that does clutches and see what they say. I sure don't mean to flame you here...but it sounds like you might be over your head with this one, so a good tranny shop (clutch) might get you on the right track. There are a couple of good tests for the clutch that the shop can perform. I'm betting that's it.

Not flamed at all, I said any ideas will help. I will try the clutch and see, My question is though even if I'm not shifting(cruising at 60mph and punch it to pass someone) would that be my clutch slipping or does that only happen on shifting?

It's my clutch.....It took it to my other mechanic and it's slipping like crazy. I got one price for 1k and I just thought I'd try the dealer.....for kicks...2k maybe more:rolleyes:

Neways I'm gonna get one more quote and go from there.

yes normally a clutch slip is most noticable in the low to mid rpm's in 4th or 5th gear under WOT. you'll see the rpm's "walk" up....

mine does the same thing but i drive a sport. i took it to the dealership and they are charging $95 to see whats wrong with it. i'm pretty sure it needs a new valve body and solenoid. and its covered under my after market warranty. so it should cost me about $200. and i'm goin to have them replace the window regulators also.