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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Cobra is Missing and Shuttering, Sounds Like a Train!

  • Thread starter Thread starter nazstang
  • Start date Start date Nov 10, 2008

nazstang

Member
Mar 26, 2004
204
0
16
Rhode Island
Nov 10, 2008
#1
  • Nov 10, 2008
  • #1
Hey guys, i've got myself a weird situation here. I just finished rebuilding my rearend, and repainting my whole motor, so i had it all torn apart. While apart, i checked the normal stuff like the plugs, gasket surfaces, vac hoses and such, and it was all good. I put here together minus the smog pump(left it in the extra parts pile ) and it ran perfect for over a week.

Then i got some gas(93 as always) and drove to work. On the way home, it started to stumble and stutter, it was raining so i was going slow but it was noticeable. Now i go to take the car out and this thing is chugging like a damn train! It is hesitating sooo bad, aslong as there is load on the motor, she's limp. Idles crappy, motor shakes like ricer at FunFordWeekend. What's going on?

So for a quick history.
-Has new pip spring 08
-Has ne ignition module spring 08
-Has new plugs
-New msd cap n rotor
-Fresh fluids
-Clean MAF and IAC
-Timing at 14
-FP at 38
Stockish motor, just boltons.

So what do you think?!!!!

I'm thinking swap the plug wires(these are all low mileage tho), and i only had time to throw 1 new O2 sensor in a while back, so ill throw the other in. Perhaps a vac leak??I'm lost fellas
 
N

neoxaero

New Member
Oct 3, 2008
39
0
0
Nov 10, 2008
#2
  • Nov 10, 2008
  • #2
my first thought would be a tank full of bad gas

Did you goto a different station? I stay away from the old stations with the crappy pumps for 93 octane... Its not a big seller, so it sits in tanks longer and tends to get more water in it...
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
9,297
1,641
214
Acworth, GA
Nov 11, 2008
#3
  • Nov 11, 2008
  • #3
neoxaero said:
my first thought would be a tank full of bad gas

Did you goto a different station? I stay away from the old stations with the crappy pumps for 93 octane... Its not a big seller, so it sits in tanks longer and tends to get more water in it...
Click to expand...

+1 Throw some water remover in the tank and see what happens.

Kurt
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Nov 11, 2008
#4
  • Nov 11, 2008
  • #4
My 03 would do that in the rain. Ended up being o2s
 

nazstang

Member
Mar 26, 2004
204
0
16
Rhode Island
Nov 11, 2008
#5
  • Nov 11, 2008
  • #5
This is weird, i got the gas from the same Hess place i've gone to for years.... but, stuff happens. I did notice though that i left the smog hose uncapped(i was quite a few beers deep that day). I did cap it yesterday and it still ran the same, could that be an issue?
Yesterday i threw in some lucas cleaner in, but i'll get some drier tonight. As for if it was a vac leak, what's the best way to hunt one down(besides spraying car cleaner everywhere and ruining my new paint).
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Nov 11, 2008
#6
  • Nov 11, 2008
  • #6
Is cel on?moisture around coils .is it always running crappy or just when accelerating?
 

nazstang

Member
Mar 26, 2004
204
0
16
Rhode Island
Nov 11, 2008
#7
  • Nov 11, 2008
  • #7
No Cel , and it runs like crap right off the back, sometimes stumbling down and turning off. I just don't get how it was fine for 15 miles after the new gas, and then it just went limp
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Nov 11, 2008
#8
  • Nov 11, 2008
  • #8
Beer beer and what ever else .happens all the time .how much gas is in tank now?if you feel everything you did is perfect and car was fine i would empty tank and see if its ok with new gas vs add stuff.why go to far to fast.save old gas might not be bad
 

nazstang

Member
Mar 26, 2004
204
0
16
Rhode Island
Nov 12, 2008
#9
  • Nov 12, 2008
  • #9
Yeah, i filled the tank, so i guess it's gonna be a pain. I threw some drier in it last night and will try tonight, but this is strange. If it's not the gas, what the hell could it be!
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Nov 12, 2008
#10
  • Nov 12, 2008
  • #10
You can use a hose connected to your fuel line and turn key?depends on how many things were removed and parts that were repaired.most of the time its something u did.as u know air fuel spark.vacuum is air related yes.fuel needs volume pressure and injector to pulse on time.than electric.your car is running so now its easy.read your car.does it idle smooth? To go faster it needs more timing fuel and air .you did touch ur dizzy.when i had mine out last month i got a new vacuum harness.it was like 70bucks .those mini lines crack and also clog.Let me know if this helps
 
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