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Rough Idle / Running Hot

  • Thread starter Thread starter mike3488
  • Start date Start date Sep 15, 2011

mike3488

New Member
May 23, 2010
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Sep 15, 2011
#1
  • Sep 15, 2011
  • #1
Hey guys, I know there are similar threads out there but every set up is different so I decided after much research to start this one and get your thoughts..

I have 88 mustang gt. Mods so far are:

mass air/a9L install (year ago)

cobra upper/lower intake
GT40 heads
65mm TB
73mm Mass air calibrated
bbk headers
accel 19lbs injectors
cold air fender intake

Initial start up went smooth, rough at first as expected. Did a few cold starts, let the car run for 10-15 to get up to temp then shut it down for 5 hours. The temp got to roughly 200? (stock temp gauge isnt much help but sat right in the middle) which seems like its a little higher than it used to be. So anyway, After a few start ups, the car idle eventually evens out and stays running, but when I turn it off and turn it back on if I dont give it gas it stalls. Today I decided to drive it to put some higher octane gas in it, the temp stayed consistant in the middle, but when I got to the gas station, put it in park it stalled again. Driving home I decided to give it a little push, nothing major, just to get it up to 3000 rpm and the temp shot way up, rolled into the drive way and stalled again. I replaced the TFI module about a year ago so doubt its that.

couple of things im thinking:
1. do i need a fuel pressure regulator with the new injectors?
2. do i possibly have a coolant problem?
3. sensor problem?
4. timing problem?

88 Mustang Gt - Second Start Up - YouTube is a link to my second start up. any suggestions?

Thanks!!
 

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Sep 15, 2011
#2
  • Sep 15, 2011
  • #2
See the "Surging Idle Checklist for help with all your idle/stall problems.

The quick and easy way to dump the codes is in there too, and all you need to do it is a paper clip! The first two posts contain all the fixes & updates. At last count there were 24 possible causes and fixes for surging idle/stall problems. I continue to update it as more people post fixes or ask questions.
 
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