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Can ANYONE please help me..

  • Thread starter Thread starter 9646gt
  • Start date Start date Apr 12, 2005
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9646gt

Member
Apr 7, 2005
595
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Holloman AFB,NM
Apr 12, 2005
#1
  • Apr 12, 2005
  • #1
OK I am running out of money trying to fix my 96 GT...it is running fine during normal driving...when you accelerate quickly or go WOT it stumbles and sounds so horrible...I replaced the plugs with NGK t55's and they came gapped at 54 I also SEA Foamed the motor and it smoked like crazy of course...even changed fuel filter...The car ran EXCELLENT right off the bat..then after about a tank and a half of gas it is running HORRIBLE again..changed plugs with Auto Lite 764 coppers and it is STILL hesitating...I gapped them at 53 (between 52 and 54 like told) and it hasnt helped..if anything it is almost a tad worse! The plug wires look to be brand new (had the car only 2 weeks) ford racing wires and like i said they seem GREAT..ran a bottle of fuel injector cleaner with no luck...cleaned CAI and still no luck...what can I try that wont cost me the last few bucks I have? Check engine code says stopped up cats bc the cats are gone...someone PLEASE help me out at 2.41 a gallon 14 miles to the gallon is killing me!
 
K

Kilgore Trout

Fried or Broiled ?
10 Year Member
Mar 30, 2005
4,749
95
134
Apr 12, 2005
#2
  • Apr 12, 2005
  • #2
Clean MAF, IAC

Replace PCV

Reset PCM
 
9

97gtblue

New Member
Apr 11, 2005
283
0
0
pensacola,florida
Apr 12, 2005
#3
  • Apr 12, 2005
  • #3
what grade gas are you running
 

9646gt

Member
Apr 7, 2005
595
3
18
Holloman AFB,NM
Apr 12, 2005
#4
  • Apr 12, 2005
  • #4
Will clean and or replace all of the above ASAP...
as for gas I have ran 87 89 93 and 93 with ocatane booster ..right no I am running 93 with fuel inj cleaner with no luck...This is very aggrivating..I love mustangs and now I finally have a GT and have a problem I can't solve..kinds hard to drive like this heh
 
P

PowerSplash93

Member
Dec 25, 2004
42
0
6
Apr 12, 2005
#5
  • Apr 12, 2005
  • #5
try the tps if that doesnt fix it. it may have a bad spot in it.
matt
 

CanadaStang

New Member
Sep 7, 2003
2,093
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Mb
Apr 12, 2005
#6
  • Apr 12, 2005
  • #6
9646gt said:
OK I am running out of money trying to fix my 96 GT...it is running fine during normal driving...when you accelerate quickly or go WOT it stumbles and sounds so horrible...I replaced the plugs with NGK t55's and they came gapped at 54 I also SEA Foamed the motor and it smoked like crazy of course...even changed fuel filter...The car ran EXCELLENT right off the bat..then after about a tank and a half of gas it is running HORRIBLE again..changed plugs with Auto Lite 764 coppers and it is STILL hesitating...I gapped them at 53 (between 52 and 54 like told) and it hasnt helped..if anything it is almost a tad worse! The plug wires look to be brand new (had the car only 2 weeks) ford racing wires and like i said they seem GREAT..ran a bottle of fuel injector cleaner with no luck...cleaned CAI and still no luck...what can I try that wont cost me the last few bucks I have? Check engine code says stopped up cats bc the cats are gone...someone PLEASE help me out at 2.41 a gallon 14 miles to the gallon is killing me!
Click to expand...

What was the cel code #?
 

9646gt

Member
Apr 7, 2005
595
3
18
Holloman AFB,NM
Apr 12, 2005
#7
  • Apr 12, 2005
  • #7
CanadaStang said:
What was the cel code #?
Click to expand...

I dont remember exactly what the CEL code was but i think it was a 40 something and the guy at auto zone said it was pointing to the cats being plugged...
 

Thundermouse

Member
Sep 17, 2003
168
3
18
Decatur, GA
Apr 12, 2005
#8
  • Apr 12, 2005
  • #8
as long as it won't ping, run the lowest octane gas
 

CanadaStang

New Member
Sep 7, 2003
2,093
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Mb
Apr 12, 2005
#9
  • Apr 12, 2005
  • #9
9646gt said:
I dont remember exactly what the CEL code was but i think it was a 40 something and the guy at auto zone said it was pointing to the cats being plugged...
Click to expand...

Hmmm.... I wonder if there were any other codes that came up? There are 4 different codes pertaining to the catalyst, without knowing which one or if there was more than the one code it's pretty hard to pin point. If you could get the code or codes I'm sure we could help you out.
Would it be one of these: PO420
PO421
PO430
PO431
 

9646gt

Member
Apr 7, 2005
595
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Holloman AFB,NM
Apr 12, 2005
#10
  • Apr 12, 2005
  • #10
i want to say it was 420 but i could be wrong ...seems like there was either a 0 or 2 at the end...should i buy coil packs? Maybe worth while to change the TPS or IAC? they are all three kinda pricey but I really want to pin point this and get it taken care of...I dont like to drive it with it acting up and risk damaging it ..
 

9646gt

Member
Apr 7, 2005
595
3
18
Holloman AFB,NM
Apr 13, 2005
#11
  • Apr 13, 2005
  • #11
I am going to try checking MAF, TPS,IAC and maybe even plug wires with a volt meter..where can I find the propper specs for these? I know I need to test the ohms but I need to know what a normal reading is...will my Haynes manual tell me? Thanx for all the help so far...
 

bham_gt

New Member
Sep 21, 2004
94
0
0
Birmingham, AL
Apr 13, 2005
#12
  • Apr 13, 2005
  • #12
Have you checked to make sure your plug wires aren't rubbing against any metal that could be grounding them out? If they've been changed especially, one or more of them could be rubbing somewhere.
 

gtstangrunner

Member
Sep 21, 2004
61
0
6
Litchfield Park, AZ
Apr 13, 2005
#13
  • Apr 13, 2005
  • #13
How is the car at idle? If its only hesitating at WOT it could be a fuel delivery problem. Did you check the pump, I saw you changed the filter. Your computer could be spazzing out on you. My car started hesitating real bad and about 3 days later the headgasket blew . I had looowwww compression in like every cylinder. I would try to get it on the dyno and that will most likely pin point the problem.
 

Dan_Soprano

15 Year Member
May 7, 2003
7,410
53
129
Jacksonville, FL
Apr 13, 2005
#14
  • Apr 13, 2005
  • #14
9646gt said:
OK I am running out of money trying to fix my 96 GT...it is running fine during normal driving...when you accelerate quickly or go WOT it stumbles and sounds so horrible...I replaced the plugs with NGK t55's and they came gapped at 54 I also SEA Foamed the motor and it smoked like crazy of course...even changed fuel filter...The car ran EXCELLENT right off the bat..then after about a tank and a half of gas it is running HORRIBLE again..changed plugs with Auto Lite 764 coppers and it is STILL hesitating...I gapped them at 53 (between 52 and 54 like told) and it hasnt helped..if anything it is almost a tad worse! The plug wires look to be brand new (had the car only 2 weeks) ford racing wires and like i said they seem GREAT..ran a bottle of fuel injector cleaner with no luck...cleaned CAI and still no luck...what can I try that wont cost me the last few bucks I have? Check engine code says stopped up cats bc the cats are gone...someone PLEASE help me out at 2.41 a gallon 14 miles to the gallon is killing me!
Click to expand...
so the car does or does not have cats?
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Apr 13, 2005
#15
  • Apr 13, 2005
  • #15
9646gt said:
The car ran EXCELLENT right off the bat..then after about a tank and a half of gas it is running HORRIBLE again..
Click to expand...

by this do you mean it ran great right after the fuel filter change?? then ran horrible after a tank or so of fuel.. if this is the case you may have something contaminating the fuel supply.. and clogging the fuel filter...

please provide more info..
 

9646gt

Member
Apr 7, 2005
595
3
18
Holloman AFB,NM
Apr 13, 2005
#16
  • Apr 13, 2005
  • #16
The car doesn't have cats its straight pipe from headers to mufflers...It seems to idle jsut fine..I think it has a bad heater core but that doesn't explain the hesitation...i am leaning towards the TPS not reporting WOT to the ECU...if someone can tell me how to test the ohms of the tps with a volt meter it may tell me right away..I am going to have the codes ran again today if it doesnt rain and have them run with engine running this time also...

As far as fuel delivery the fuel pressure gauge under the hood shows at or above 40 even when reving the motor while idleing..it goes up but never really seems to drop any... could the seamfoam I ran into the intake manifold have been what made it run so well the first time? meybe something is building up very quickly and this removed it? i sucked it straight into a vacume and the engine NEVER killed itself out like i figured it would...

thanks so much for your guys help and PLEASE keep any suggestions comming...

also is it bad if the plug wires cross over each other quite a bit? I always heard it was.... this sputter has to be fixed
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Apr 13, 2005
#17
  • Apr 13, 2005
  • #17
9646gt said:
I dont remember exactly what the CEL code was but i think it was a 40 something and the guy at auto zone said it was pointing to the cats being plugged...
Click to expand...


there is no code for the cats being plugged... this is why you dont listen too the auto zone guy... look at the scan tool yourself and write the code down..

there is no code 40 and no code for cats being "stopped" up

since your car has no cats i would ignore the cat codes... probally a cat ineffecincy code..

but keep in mind the computers may have built in logic too create driveability problems when cat codes have been running for awile... ( this is done so you bring the car in too have the emmisions work done) i know GM has done this.. and i would not be surprised if ford has done this on early obd2 cars...

to fix the cat codes all you need is mil eliminators...

i stoped into a auto zone once with a friend of mine in his truck too get a code read.. i already knew what was wrong with it i just wanted too be a dick and **** with the autozone guy..

the truck was a 2001 explorer with a po401 innsuficent egr flow... and this guy reads the code and then trys too sell me a egr valve

i told him why he was wrong and explaned too him that the DPFE sensors on just about all fords built around that time goes.. ( these are the small black sensors.. not the big old metal ones.. you can tell if your car has one because it's a standalone unit with no bracket) and then i told him he should not try and diag cars.. just give the code and let them take it from there..
 

9646gt

Member
Apr 7, 2005
595
3
18
Holloman AFB,NM
Apr 13, 2005
#18
  • Apr 13, 2005
  • #18
MikeZ28 said:
by this do you mean it ran great right after the fuel filter change?? then ran horrible after a tank or so of fuel.. if this is the case you may have something contaminating the fuel supply.. and clogging the fuel filter...

please provide more info..
Click to expand...

Sorry i was so aggrivated that I messed up there..I changed the fuel filter last ..it ran GREAT after only seafoam and plugs ..i changed filter as a last resort after the tank and a half where it started running crappy again...it doesnt even sound right when you rev the motor at idle....sounds nothing like it did when it was running so well....
 

9646gt

Member
Apr 7, 2005
595
3
18
Holloman AFB,NM
Apr 13, 2005
#19
  • Apr 13, 2005
  • #19
MikeZ28 said:
there is no code for the cats being plugged... this is why you dont listen too the auto zone guy... look at the scan tool yourself and write the code down..

there is no code 40 and no code for cats being "stopped" up

since your car has no cats i would ignore the cat codes... probally a cat ineffecincy code..

but keep in mind the computers may have built in logic too create driveability problems when cat codes have been running for awile... ( this is done so you bring the car in too have the emmisions work done) i know GM has done this.. and i would not be surprised if ford has done this on early obd2 cars...

to fix the cat codes all you need is mil eliminators...
Click to expand...

Ill do everything in my power to get those codes ASAP ...i am just having a hard time understanding why after that tank and a half of gas the whole car turned around again...all i did was plugs and the seafoam...Look like I will learn alot from this experience heh
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Apr 13, 2005
#20
  • Apr 13, 2005
  • #20
9646gt said:
Ill do everything in my power to get those codes ASAP ...i am just having a hard time understanding why after that tank and a half of gas the whole car turned around again...all i did was plugs and the seafoam...Look like I will learn alot from this experience heh
Click to expand...


yeah that is kind of weird how it ran well at first...

i dont like the use of aftermarket plugs in ford motors.. use the motorcrafts.. I have had so many problems related too non-motorcraft plugs in the past... now it's the first thing i look for..

when did it first start running like crap.. after or before the first plug change...

plus does it idle ok.. i need too know this too help..
 
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