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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Pi Swasp Help

  • Thread starter Thread starter Angel Rivera
  • Start date Start date Sep 4, 2014

Angel Rivera

New Member
Jul 8, 2014
19
0
1
Rochester NY
Sep 4, 2014
#1
  • Sep 4, 2014
  • #1
Hello,

I just finished my PI swap, brand new heads and intake, and I'm experiencing idle issues. I will start the car an it runs fins for a few seconds and dwindles down until it stalls out. It does this while driving for a bit until the temperature gets to about half way. Once it is warmed up it runs pretty good but shifting the idle will drop pretty fast, but wont stall out. Any advice? I had the swap done at a professional shop to make sure I didn't goof timing, and I have checked all vacuum lines but haven't sen anything weird. Any advice? I am currently waiting for a tune from BAMA and running 90 octane with no ethanol. The car is old but only has 38k on it so its a really health motor and was running solid prior to the swap.
In addition all new gaskets were used. It shot out a p171 and p174 code which led me to check the vacuums but after clearing it and running it it has not come back on.
Any and all suggestions are welcome!
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
Sep 5, 2014
#2
  • Sep 5, 2014
  • #2
Just wondering. Was the tune built for a PI swap? Are you aware how a PI head swap changes the CR?
 

Angel Rivera

New Member
Jul 8, 2014
19
0
1
Rochester NY
Sep 6, 2014
#3
  • Sep 6, 2014
  • #3
Yes, it raises the compression ratio to 10.3:1 or around there I believe. The tune is for the PI swap and for the gas i usually run ( 90 no eth). Prior to the tune it had these issues. After the tune it is running better but the idle still tends to flux and possibly drop during the initial morning start. After its a temperature it is fine all day. I was thinking of raising the idle a bit just so it does not drop as far down.
 
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