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a tiny tiny gas, car drops rpms?

  • Thread starter Thread starter custom89stang
  • Start date Start date Aug 12, 2005
C

custom89stang

New Member
Dec 9, 2003
705
0
0
Seattle, WA
Aug 12, 2005
#1
  • Aug 12, 2005
  • #1
okay so i start my car, let it warm up at 1200rpms, then it drops (rough idle) to the normal 850 or W/E and i have my foot on the clutch and give it just a tiny tiny bit of gas and the RPMS drop to like 500 and it feels like its gonna die but it never does, then i give it a tiny tiny more bit of gas and everything is fine and rpms go right back up....i can do this conistantly, like....give it JUST tiny bit amount of gas to make it drop VERY low (and then the computer saves it or something everytime?)....... CURIOUSLY this goes away after the car is warm...ANY IDEA WHAT IT COULD BE DOING THIS? the EEC maybe?
 

Dean85GT

New Member
Nov 27, 2004
502
1
0
Thorold, Ontario, Canada
Aug 12, 2005
#2
  • Aug 12, 2005
  • #2
my carbed car does that all the time...Its just how it is LOL
 

90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
2,773
17
89
Dallas, GA
Aug 12, 2005
#3
  • Aug 12, 2005
  • #3
May had idle issues. Clean the TB and IAC. Run the engine to full operating temprature. Then disconnect the IAC and use the idle set screw to your desired idle, then set the TPS signal voltage to .99. Plug IAC back in, start car, let it idle a minute or two then see if the problem is fixed.

I had this issue with a 97 Ford Ranger 2.5 OHV the other day. The A/C would come one but after revved up a little it would shut off, a few seconds later the A/C compresor would kick on, then imediatly shut back off, I noticed the RPM's were dropping. After the other switches were checked, a coworker suggested to clean the TB, I did this and did the idle reset procedure as I mentioned, not only made the A/C work, but the truck ran much better (about as good as a 4 banger ranger could run).
 
C

custom89stang

New Member
Dec 9, 2003
705
0
0
Seattle, WA
Aug 12, 2005
#4
  • Aug 12, 2005
  • #4
thx
 

Euphoric306

New Member
Apr 5, 2004
905
0
0
Aug 13, 2005
#5
  • Aug 13, 2005
  • #5
i got a ? 90mustanggt.... where in that process do u shut off the car, and how do u set tps voltage (voltmeter of course), but what adjusts it?
 
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