Please Read-98 Cobra Acceleration Problem

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MacDiesel

New Member

Feb 5, 2004

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Feb 18, 2004

#1

• Feb 18, 2004

• #1

I Have Tried To Post This Before, But I Gues I Didn't Explain Myself Clearly Before. Basically, When I Take Off In 1st Gear My Car Accelerates Like Normal. When I Shift To Second Gear And Accleerate My Car Kind Of Stalls Out Like It Can't Breathe Or It Is Not Getting Enough Fuel. Same Thing 3rd, 4th, And 5th Gear. If I Am Really Putting The Pedal To The Medal It Doesn't Do It As Bad. I Change Spark Plugs And Pcv Valve And It Helped Out A Little Bit. Could Anyone Please Help? It Has 38500 Miles On It. Off Road H-pipe Flowmasters, And K&n That Is All That I Know Off. Thanks To All In Advance

 

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COBRA_SVT_VERT

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Feb 3, 2002

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JawJa

Feb 18, 2004

#2

• Feb 18, 2004

• #2

Spark plug wires?

Check engine light?

Have you pulled codes to make sure nothing's stored from long term?

 

M

MacDiesel

New Member

Feb 5, 2004

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Feb 18, 2004

#3

• Feb 18, 2004

• #3

COBRA_SVT_VERT said:

Spark plug wires?

Check engine light?

Have you pulled codes to make sure nothing's stored from long term?

Click to expand...

I DID NOT PUT NEW WIRES ON, BUT I WOULD THINK THAT THEY WOULD BE TOO BAD WITH ONLY 38500 MILES. ALSO, THE CHECK ENGIEN LIGHT IS NOT ON NOR HAVE I PULLED CODES.

 

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tama

New Member

Dec 27, 2003

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San Jose, CA

Feb 18, 2004

#4

• Feb 18, 2004

• #4

my 98 used to do that till I got used to the clutch. Anyway, Try using a fuel injector cleaner first, might help, second, check the k&n, you will be surprised on how quick they get dirty, I clean mine every six months. If your spark plug wires are the stock ones, you should definetly change them. It might just be you. If you ever get a chance, run it at a local track to see how it runs, I used to think mine was a slug till I ran 14.1 at the track which is normal.

 

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Thunder5.0

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Jul 25, 2003

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Feb 19, 2004

#5

• Feb 19, 2004

• #5

Change the fuel filter and run 93 octane.

 

M

MacDiesel

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Feb 5, 2004

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Feb 19, 2004

#6

• Feb 19, 2004

• #6

Thunder5.0 said:

Change the fuel filter and run 93 octane.

Click to expand...

i will change the fuel filter and i do run 93 octane in it, but the person before might not have.

 

Tat98Cobra

Founding Member

Nov 2, 2002

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Feb 19, 2004

#7

• Feb 19, 2004

• #7

MacDiesel said:

i will change the fuel filter and i do run 93 octane in it, but the person before might not have.

Click to expand...

Has it done this since you bought that car?
Check and make sure all air clamps are tight and there's no other leaks - could be an un-metered air problem.
I would definately check for codes too - for all you know, the mil light could have been turned off by a chip.

peace

 

DCOBRA97

Member

Oct 14, 2002

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Bel Air MD

Feb 19, 2004

#8

• Feb 19, 2004

• #8

I would suggest to check the fuel pressure. Even with the low miles and the fact that it is only 6yrs old if the tank gets below a 1/4 of a tank I have heard that the excess heat causes the pump to work harder, ie; wearout faster?
Mine is a 94 and with only 49,000 I wll be replacing the pump before much longer............because I have been stuck when they go out and it is not fun.

 

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sLOWSVT

New Member

Apr 16, 2003

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Lockport, IL

Feb 20, 2004

#9

• Feb 20, 2004

• #9

Maybe thats my problem too...

Where do you check the pressure? My father has a gauge, but we havent really played with my car yet?

 

D

drizztkun

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Aug 10, 2003

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Montreal Quebec

Feb 20, 2004

#10

• Feb 20, 2004

• #10

The o2 sensor could do something like that too

 

R

Roush21

New Member

Dec 31, 2003

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Feb 21, 2004

#11

• Feb 21, 2004

• #11

MacDiesel said:

I Have Tried To Post This Before, But I Gues I Didn't Explain Myself Clearly Before. Basically, When I Take Off In 1st Gear My Car Accelerates Like Normal. When I Shift To Second Gear And Accleerate My Car Kind Of Stalls Out Like It Can't Breathe Or It Is Not Getting Enough Fuel. Same Thing 3rd, 4th, And 5th Gear. If I Am Really Putting The Pedal To The Medal It Doesn't Do It As Bad. I Change Spark Plugs And Pcv Valve And It Helped Out A Little Bit. Could Anyone Please Help? It Has 38500 Miles On It. Off Road H-pipe Flowmasters, And K&n That Is All That I Know Off. Thanks To All In Advance

Click to expand...

First I would check the fuel filter, then the air filter cuz thats your cheapest way out. If that doesnt work it would probably be your fuel pump. Try also run some fuel injector cleaner thru your injectors maybe they are dirty. These are the basic starting points.

 

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SPICOLI

New Member

Feb 10, 2004

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Edwards California

Feb 26, 2004

#12

• Feb 26, 2004

• #12

I had a somewhat similar problem with my 98 Cobra 3 weeks ago. It ended up that the small plastic cover on the top of my fuel pump had worked its way loose and it was fluctuating the amount of gas it was pumping throught the line...I just tightened the 2 screws that held it on the outlet side of the pump and it runs perfect....Just one of those off the wall things that you might want to check if the obvious dosent fix it...Good Luck

SPICOLI

 

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sirhisss

Founding Member

Dec 12, 2000

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Quincy, WA

Feb 27, 2004

#13

• Feb 27, 2004

• #13

Here's what I would suggest:

Considering that you have changed your plugs. BTW I do hope that you put antisieze on the threads!

1. Change that fuel filter! You have 38K miles of dirt in it.
2. Make sure your KN air filter is clean! Quick way is replace with new if you are pressed for time.
3. Check that all of the air track clamps are tight.
4. Check that your plug wires are fully seated on the plugs. Also, you should have applied silicone dielectric grease to the inside of the plug boots. If you did not, then you could have some of your spark going on the outside of the plug. I've seen it happen many times.
5. Check your fuel pressure at the shrader valve Key on engine off. (not started). You should have 30-35 psi.
6. If you have a code reader check for any pending codes. If not, pull battery lead, wait 30 minutes then reconnect.
7. Take it for a "cruise". Will probably run crappy for a few miles as the computer relearns.

That is the cheap correction.

Consider replacing your plug wires. IMO plug wires should be tossed after 3 years anyway because the core has absorbed moisture and the resistance has increased thereby reducing your spark. Stock wires are in the $100 range.

Good luck!

 

S

spanky442

New Member

Feb 3, 2004

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Feb 27, 2004

#14

• Feb 27, 2004

• #14

Sounds like an 02 sensor possibly. On my 93, when I put the h-pipe I had a similiar issue with went away when I replaced the 02 sensors.