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Poor Running 86 GT

  • Thread starter Thread starter ItalianStanger
  • Start date Start date Apr 22, 2004
I

ItalianStanger

Founding Member
Oct 12, 2000
93
0
0
Addison, IL
Apr 22, 2004
#1
  • Apr 22, 2004
  • #1
I have a Kenne Bell S/C 6PSI Kit on my 86 Mustang GT. Recently, the car started running very choppy when the MAP Sensor is connected. Although, when it is disconnected, it runs smooth, until it dies out. If I adjust the TPS sensor for idle, maybe it won't die out.

Any ideas of why this is happening? I am getting correct fuel pressure. I have no vaccum leaks. Why would the car be ideling choppy?

Also, the car seems to be running very rich. I have a 255 lph in tank fuel pump, although I believe the injectors are stock. Would I need an adjustable fuel pressure regulator?
 

cavallonero

Founding Member
Mar 28, 2002
86
0
0
Denver
Apr 22, 2004
#2
  • Apr 22, 2004
  • #2
I had a similar problem a few years back on my four banger... it ended up being the O2 sensor. This would also make sense with yours if its running rich.
Good luck
 

N8Miller

I need NOS....make it 2 of the big ones
Founding Member
Jul 26, 2000
2,661
0
0
Kingston, PA, USA
Apr 22, 2004
#3
  • Apr 22, 2004
  • #3
do you have the mass air conversion? i dont know if you need it, but it might help. did it just start after the blower install???
 
I

ItalianStanger

Founding Member
Oct 12, 2000
93
0
0
Addison, IL
Apr 23, 2004
#4
  • Apr 23, 2004
  • #4
My 86 GT is speed density, so I do not have the Mass Air, nor did I convert the car to mass air. I have had the S/C on for about a Year and a Half. Check my signiture for other modifications.
Here is the story: I was driving home one day on the highway and I noticed that the car was idling a 1,500 RPM. I took it home and checked it out, I couldn't find anything.
I took it to a good mechanic of mine who told me that a vacuum hose came off and they just reconnected it for me. When I went to pick up the car, it started, idled choppy for 5 sec. and died. I left it with them and they couldn't find the problem.
Now I have taken it to a speed shop, they have set the timing correctly, fixed my vacuum leaks (which consisted of the PCV and the gasket between the EGR & Throttle Body). The car idles, but it is choppy. He says that when he disconnects the MAP Sensor, the car idles and runs fine, until it dies because the throttle may need to be opened a little more.
Although when the MAP is connected, he says that it idles choppy. He also said that the injectors don't look stock, he said their blue, and that the car smells like it's running rich.

My confusion is that the car ran fine, all of a sudden on the way home one day, the idle kicks up to 1,500 after a drive on the expressway.

Any ideas??
 
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