94 gt backfiring while driving please help

S

shanek

New Member

Mar 2, 2010

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Mar 2, 2010

#1

• Mar 2, 2010

• #1

While im driving and if I slowly push on the gas it wants to backfire and buck , but I can go ahead and hit the gas hard it will stop and clear up.

Also when comeing to a stop I can push in the clutch or take it out of gear the rpm will drop and then the car will stall . It will fire right back up.

I have put a new coil, wires,cap and rotor. What im thinking it the pick up on the distributor.

Can someone please help me.
Thanks

 

toyman

10 Year Member

Jul 19, 2007

1,944

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79

Vernon BC

Mar 2, 2010

#2

• Mar 2, 2010

• #2

shanek said:

While im driving and if I slowly push on the gas it wants to backfire and buck , but I can go ahead and hit the gas hard it will stop and clear up.

Also when comeing to a stop I can push in the clutch or take it out of gear the rpm will drop and then the car will stall . It will fire right back up.

I have put a new coil, wires,cap and rotor. What im thinking it the pick up on the distributor.

Can someone please help me.
Thanks

Click to expand...

Doesn't sound like a PIP problem. Check for fault codes if possible, clean MAF element and confirm timing. Also, I would replace the fuel and air filters if they haven't been touched in a couple of years.

 

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shanek

New Member

Mar 2, 2010

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Mar 2, 2010

#3

• Mar 2, 2010

• #3

toyman said:

Doesn't sound like a PIP problem. Check for fault codes if possible, clean MAF element and confirm timing. Also, I would replace the fuel and air filters if they haven't been touched in a couple of years.

Click to expand...

I dont know about the filters. I just got the car about 4 days ago. I did know it was doing this before i got it. But I did not think it was going to be a big problem or a hard fix. I had one a few years ago do almost the same thing and it was the pick up. Im going to get a new fuel filter tomorrow and try it.
Thanks alot

 

joeltx_2000

New Member

Jan 29, 2010

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Huffman,TX

Mar 2, 2010

#4

• Mar 2, 2010

• #4

need help i bought a sct dash scan for my 94 gt , and it won't come on , what's wrong??

 

toyman

10 Year Member

Jul 19, 2007

1,944

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Vernon BC

Mar 2, 2010

#5

• Mar 2, 2010

• #5

joeltx_2000 said:

need help i bought a sct dash scan for my 94 gt , and it won't come on , what's wrong??

Click to expand...

Wrong scan tool. The car is OBD-1 NOT OBD-11. The port you are looking for is in the engine bay on the passenger side strut tower on the fire wall side. The under dash port is there because it shares the same wiring harness as the V6 but is non functional on the GT's.

 

desertcox05

New Member

Oct 3, 2007

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south atlanta

Mar 3, 2010

#6

• Mar 3, 2010

• #6

double ck you firing order again.
you could have 2 mixed up. It's easy to do

 

R

RatStang

New Member

Feb 11, 2010

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Mar 3, 2010

#7

• Mar 3, 2010

• #7

desertcox05 said:

double ck you firing order again.
you could have 2 mixed up. It's easy to do

Click to expand...

Good Call!

View attachment 228101

 

99FiveOh

15 Year Member

May 20, 2006

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99

J-Ville, FL

Mar 3, 2010

#8

• Mar 3, 2010

• #8

And I doubt it's the fuel filter. Think about it, if it clears up when you floor it then it's not starving for fuel. I was having similar issues and I had a full fuel diagnostic (idle, driving under load and wot) and my fuel pressure never moved. I did swap my fuel filter for the heck of it and it was NASTY!

My problem ended up being the PIP sensor. Only difference from your symptoms was that mine would also ping like crazy on 10* of timing WITH 93 octane!

 

desertcox05

New Member

Oct 3, 2007

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south atlanta

Mar 3, 2010

#9

• Mar 3, 2010

• #9

also ck to make sure your harmonic balancer hasn't slipped and now your timing readings are off.

 

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shoua50

New Member

Feb 19, 2010

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Mar 4, 2010

#10

• Mar 4, 2010

• #10

sounds to me like you got a vacuum leak. under hard throttle, manifold vacuum goes away and under decel, manifold vacuum increases. the increase in vacuum under decel can bog your car down and a small vacuum leak will make it run lean under part throttle causing your misfires and bucking. rpm at idle can still be ok due to your ecu compensating for the leak.

 

ProKiller

Founding Member

Apr 26, 2002

3,064

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PA

Mar 4, 2010

#11

• Mar 4, 2010

• #11

check for vacuum leaks.

 

S

shanek

New Member

Mar 2, 2010

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0

Mar 5, 2010

#12

• Mar 5, 2010

• #12

worked on it last night for a while. I found the the TPS was falling off. someone must have drilled it to tune it and did not tighten it. will find out today if that is it.