98 Cobra with BADDDD hesitation...

R

ree11

New Member

Apr 20, 2008

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0

0

Apr 25, 2008

#1

• Apr 25, 2008

• #1

I have a 98 cobra with almost 72K miles and it has developed a very bad hesitation and shake. It hesitates in pretty much all conditions but sometimes it runs perfect. Only under about 70% throttle or higher is there no hesitation. It also has a bad shake at idle. The check engine light comes on intermittently and says it is running lean and rich in the #1 bank. I checked and replaced the spark plugs and a tiny amount of oil was on that one. I am thinking it is maybe a valve cover gasket leak?? Any help is appreciated.

Thanks,

ree11

 

stang dreamer

New Member

May 24, 2005

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0

Manchester, UK

Apr 26, 2008

#2

• Apr 26, 2008

• #2

i have a 98 cobra as well, just about covered 75,000 miles and only recently had the exact same problem. to stop the engine light i just checked the 02 sensors and replaced the bank 2 sensor. no more engine light and the idle is miles better. maybe worth checking your 02 sensors.

 

Lil'_Red_Rocket

Founding Member

Oct 10, 1999

58

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6

Lloydminster, AB.

Apr 26, 2008

#3

• Apr 26, 2008

• #3

Have you changed the plugs and wires? If they are 10 years old you may have a spark issue and it could cuse the shake at idle and the hesitation.

 

R

ree11

New Member

Apr 20, 2008

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Apr 26, 2008

#4

• Apr 26, 2008

• #4

I replaced the plugs but not the wires, but they look like they have been changed recently. They are very clean. I am installing the Steeda adjustable clutch cable tomorrow, so I will replace the O2 sensors while I am under there, and if that doesn't fix the problem I will go to the wires and check the plugs again for oil and maybe go to the valve cover gaskets from there. If that doesn't fix it then I guess to the fuel system. But I hope we dont have to go that far lol!

 

F

fiveofanatic

How to fuel a Mustang:

Founding Member

Aug 12, 1998

8,152

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76

Phoenix, AZ suburbs

Apr 27, 2008

#5

• Apr 27, 2008

• #5

Rich and lean doesn't make sense. What code # is it?

 

R

ree11

New Member

Apr 20, 2008

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0

Apr 28, 2008

#6

• Apr 28, 2008

• #6

EXACTLY!!! Not sure the code # but there were 2 codes, one said it was rich, and the other said it was lean

 

F

fiveofanatic

How to fuel a Mustang:

Founding Member

Aug 12, 1998

8,152

0

76

Phoenix, AZ suburbs

Apr 29, 2008

#7

• Apr 29, 2008

• #7

Get the codes, dude, gotta have the codes.

 

9

98'CobraSVT

New Member

Feb 23, 2008

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0

May 1, 2008

#8

• May 1, 2008

• #8

Check your MAF sensor as well