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Please help! I need some insight!

  • Thread starter Thread starter btsclan
  • Start date Start date Oct 2, 2008
B

btsclan

Member
Feb 22, 2004
64
0
6
Seattle, WA
Oct 2, 2008
#1
  • Oct 2, 2008
  • #1
Ok so, I have a question about a problem with my 87 GT. It all started when I did a new exhaust install, I went from a crappy stock system with 2 inch tail pipes to BBK headers, off-road h-pipe and flowmaster 40 catback. The car idles just fine but it sounds like it misses or cuts out when you give it gas, I have no codes in the computer and have replaced just about every sensor on the engine so my question is, when adding a new exhaust that flows way better then stock is there a chance that the car will run lean? The fuel pressure is 39psi, new senors everywhere(TPS, o2, CTS, ACT, new plugs, wires etc etc)

Could it be a bad distributor? Also when the car is cold it runs like a jem but as it warms up it starts to miss under load.

If you have any idea what this could be or any insite please let me know, it all started when I put in the new exhaust, please help your fellow stanger out.:SNSign:
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Oct 3, 2008
#2
  • Oct 3, 2008
  • #2
The exhaust itself should not present an issue.

Did you use copper plugs? Plats can cause a miss around 4K RPM.

Possible areas to keep an eye on include the TFI module and ignition coil. Both can cause a miss when hot and under load.

Good luck.
 
B

btsclan

Member
Feb 22, 2004
64
0
6
Seattle, WA
Oct 3, 2008
#3
  • Oct 3, 2008
  • #3
HISSIN50 said:
The exhaust itself should not present an issue.

Did you use copper plugs? Plats can cause a miss around 4K RPM.

Possible areas to keep an eye on include the TFI module and ignition coil. Both can cause a miss when hot and under load.

Good luck.
Click to expand...

Yeah I've heard that the TFI could go bad and cause that problem, but if it was bad would it be intermittent? When the car is cold its fine but also once warmed up when the problem is pressent from time to time it clears up and acts just fine as I drive, the problem comes and goes? So if it is going bad can it be intermittent?

Thanks for your help
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Oct 3, 2008
#4
  • Oct 3, 2008
  • #4
btsclan said:
Yeah I've heard that the TFI could go bad and cause that problem, but if it was bad would it be intermittent? When the car is cold its fine but also once warmed up when the problem is pressent from time to time it clears up and acts just fine as I drive, the problem comes and goes? So if it is going bad can it be intermittent?

Thanks for your help
Click to expand...

In general, electrical components fail or show signs of failure when they get hot. If your issue literally comes and goes (once you're up to temp) recursively, the TFI might not be at fault. I'd simply have it bench tested several times (to heat it up and simulate underhood heat).

Otherwise, it takes seeing sensory input and testing it while it acts up to find the issue.

There was a TSB regarding an inductance crossfire with the stock plug0wire routing. Be sure your wires are not leaking, new or not.

Keep trying to retrieve codes, just in case a cookie pops into the KAM (codes are stored without illuminating the CEL).

Good luck.
 
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