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Running sluggish / missfire / blinking check engine light

  • Thread starter Thread starter martylavender
  • Start date Start date Dec 2, 2008
M

martylavender

New Member
Dec 2, 2008
2
0
0
Dec 2, 2008
#1
  • Dec 2, 2008
  • #1
96 CObra
121k miles


So about 2 weeks ago, the car started running sluggish under load. If I really got on it, it was like it didnt want to go anywhere. Once I got up to over 2500 RPMs it would take off more so like normal.

Thinking it was the air filter possibly, we cleaned it. The next day the check engine light came on.

Went to Autozone and had them read the code.

P0306 and P0308 which are cylinder 6 and 8 missfire. It was suggested to change the plugs and wires, by my father in law and Autozone. So bought new plugs and wires.

Immediatly after changing them and starting the car and driving it around a bit it felt like the car was idling rough. It doesnt do the studder thing but it still feels like there is not enough power to the engine. I figured I needed to drive it around, so I drove to the gym tonight, and the check engine light started blinking when I got up to around 60 mph. I slowed down and it stopped...once I got to the gym it started doing it again for a couple seconds as I sat idling. Then stopped.

Ive read numerous things about it.....people talking about excess gas getting into the CAT, overheating it, and killing it basically.

What do you guys suggest I look at now? Should I just take it into the shop? Someone said possibly coil pack going out?
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Dec 2, 2008
#2
  • Dec 2, 2008
  • #2
Maybe not but my 03 cobra did that.never had it scanned and car ran like crap.ended up being driverside head.a compression and leakdown test on that side is where i would start
 
W

whitesvt

New Member
Nov 24, 2008
6
0
0
Dec 2, 2008
#3
  • Dec 2, 2008
  • #3
Last year when i pulled my 97 cobra out of storage it was running horrible. it felt like a miss so i did a tune up and that didnt help, my uncle said i had a vacuum leak at the intake gasket so i changed that, and that didnt help. so i let the car idle and started unpluging sensor wires and i found it. my mass air flow sensor was covered in crud. i cleaned it with carb cleaner and a knife and the cars ran great ever since. I would take a look at it, maybe you can save yourself from the headache i went through. Good luck
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Dec 2, 2008
#4
  • Dec 2, 2008
  • #4
What did car do different when you unpluged maf?
 
M

martylavender

New Member
Dec 2, 2008
2
0
0
Dec 2, 2008
#5
  • Dec 2, 2008
  • #5
Would the MAF make the car sound more throaty, and run extremely rough. Idle rough, and to the point the exchaust clanks taking off in first gear??
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Dec 2, 2008
#6
  • Dec 2, 2008
  • #6
Dumb question of the day. Do you hear what one would say exhaust leak at manifold and head ?
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Dec 2, 2008
#7
  • Dec 2, 2008
  • #7
Not what you want to hear but my 1st head blew cyl 6.my 2nd head cyl 6.
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Dec 2, 2008
#8
  • Dec 2, 2008
  • #8
I had to diagnos mine myself with knowing anything about a motor other than just changing basic parts. Something to look 4. Every time i took off inlet to tb oil was coming out .
 
S

SLVRBOY

Member
Apr 7, 2005
91
0
6
st. augustine , fl.
Dec 2, 2008
#9
  • Dec 2, 2008
  • #9
the same thing happened to my 96 cobra, it was the square distributor " blocks" . change those and see what happens. if you already changed the plugs and wores it wouldnt hurt to change those also.
 
W

whitesvt

New Member
Nov 24, 2008
6
0
0
Dec 2, 2008
#10
  • Dec 2, 2008
  • #10
when i unplugged my mass air it ran alot better so i cleaned it and that took care of the problem.
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Dec 5, 2008
#11
  • Dec 5, 2008
  • #11
Great news .
 
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