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Installed Cai Now Rough Idle

  • Thread starter Thread starter SoFlStang
  • Start date Start date Jul 31, 2013

SoFlStang

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May 22, 2013
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Jul 31, 2013
#1
  • Jul 31, 2013
  • #1
I just removed the under hood cone filter the previous owner had installed. I replaced it with a cold air intake. My car is a 1988 GT with MAF. The CAI kit I got is for foxes with MAF. I installed the CAI and got everything tightened up. I started the car and it idles horrible, around 500-600 rpm and if I give it gas it revs up and then dies. Just disconnected the battery and will reconnect and try in like 30 mins. I am going to keep searching for ideas, but figured I'd also ask you guys. Thanks.
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
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Jul 31, 2013
#2
  • Jul 31, 2013
  • #2
everything is tight around the TB? Did you use the same MAF? Is it plugged in?
 

SoFlStang

Member
May 22, 2013
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Jul 31, 2013
#3
  • Jul 31, 2013
  • #3
stykthyn said:
everything is tight around the TB? Did you use the same MAF? Is it plugged in?
Click to expand...


Yes, just rechecked all the clamps, everything is tight. Used the same MAF and it is plugged in. I ran the car about an hour before installing the CAI, and it ran fine. The previous filter was pretty dirty, not sure if that matters, I was thinking maybe the car needs to reset itself from having a restricted airflow?
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
5,232
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gainesville
Jul 31, 2013
#4
  • Jul 31, 2013
  • #4
i highly doubt that. did you spray the filter with filter oil? If so you may have some in the MAF now which will cause these symptoms. Huge problem with a few of the aftermarket filters.
 

SoFlStang

Member
May 22, 2013
87
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Jul 31, 2013
#5
  • Jul 31, 2013
  • #5
I did not spray it with any oil. I was just reading about resetting the idle, do you think its worth trying? Or putting the old filter back on and seeing how it runs?
 

f8tlfiveo

My wife likes my spool and blow-off valve.
Aug 8, 2007
1,585
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Lancaster, PA
Jul 31, 2013
#6
  • Jul 31, 2013
  • #6
Yeah, I had this problem. The oil coated the sensor and screwed it up. Cleaned the sensor with electrical parts cleaner and back to normal
 

SoFlStang

Member
May 22, 2013
87
1
19
Jul 31, 2013
#7
  • Jul 31, 2013
  • #7
Its running fine now. I disconnected the IAC and adjusted the idle to around 700-800 and let it idle for a minute. Shut it off and connected the IAC. Checked the voltage on the TPS then disconnected the battery for 5 mins. Put the terminals back on and started it up, ran nice. Took it for a short drive, about a mile, and it ran nice. Maybe it was what I did above, maybe oil from the filter got in the MAF and it cleaned off, maybe something was stuck and worked loose, I will never know for sure. So, hopefully all is well.
 

jrichker

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Jul 31, 2013
#8
  • Jul 31, 2013
  • #8
Your idle setting
SoFlStang said:
Its running fine now. I disconnected the IAC and adjusted the idle to around 700-800 and let it idle for a minute. Shut it off and connected the IAC. Checked the voltage on the TPS then disconnected the battery for 5 mins. Put the terminals back on and started it up, ran nice. Took it for a short drive, about a mile, and it ran nice. Maybe it was what I did above, maybe oil from the filter got in the MAF and it cleaned off, maybe something was stuck and worked loose, I will never know for sure. So, hopefully all is well.
Click to expand...

Your idle setting procedure is incorrect. You guys with idle/stall problems could save a lot of time chasing your tails if you would go through the Surging Idle Checklist. Over 50 different people contributed information to it. The first two posts have all the fixes, and steps through the how to find and fix your idle problems without spending a lot of time and money. I continue to update it as more people post fixes or ask questions. You can post questions to that sticky and have your name and idle problem recognized. The guys with original problems and fixes get their posts added to the main fix.

It's free, I don't get anything for the use of it except knowing I helped a fellow Mustang enthusiast with his car. At last check, it had more than 125,000 hits, which indicates it does help fix idle problems quickly and inexpensively.
 
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