strange idle problem

[89streetbeast]

working with an 88 gt speed density aod car. ok, when i start my car on a cold start it idles fine for about 15 seconds then starts to spudder just a bit. if you lightly press the throttle it almost cuts out but if you press a little more it almost sounds like a overloaded carburator. its kind of hard to explain what its actually doing. but if you hold the rpm's to about 1500 for 30-45 seconds it idles fine and runs good. all that i have done since i got the car was remove ALL of the smog equipment including the egr related stuff and o2 sensors. are the speed density computers that sensitive about smog and o2's than the mass air cars? never had a prob with the 89 gt when i removed all of its stuff. it almost sounds like it had a lopey cam in it when it has its fit lol.

thanks

 

[jrichker]

. ...all that i have done since i got the car was remove ALL of the smog equipment including the egr related stuff and o2 sensors. ...
thanks

Removing the O2 sensors is a big NO NO. They are some of the most important sensors that the computer uses to control the engine. No O2 sensors means the engine runs in Emergency Failure Mangement mode or Limp mode with decreased performance and fuel economy. The only reason you don't see the Check Engine light growling at you is that it doesn't work in 87-88 5.0 Mustangs.

Removing the smog equipment does not make these computer controlled cars faster. All it does is make the computer go into limp mode, which reduces performance.

Here's a book that will get you started with how the Ford electronic engine control or "computer" works.

Ford Fuel Injection & Electronic Engine Control 1988-1993 by Charles Probst :ISBN 0-8376-0301-3.

It's about $25-$35 from Borders.com see http://www.amazon.com/ . Select boo...very good, and I found it to be very helpful.

 

[Modular2v]

Speed density or not....your car still NEEDS o2 sensors!

 

[2000xp8]

I've yet to figure out why people think it's ok to remove o2 sensors.

 

[hotcobra03]

I've yet to figure out why people think it's ok to remove o2 sensors.

Posted via Mobile Devicemy guess is most werent born when carbs were used.the 02s are like the fuel and air adjustments.

 

[89streetbeast]

forgot to mention before that it has done this prior to the removal of said parts. so me removing those items had no effect on what its doing now. i'll have more time to look at it tomorrow to see if i can figure anything else out on it.

 

[jrichker]

Fix the missing O2 sensor problem first, then see the "Surging Idle Checklist for help with all your idle/stall problems. Everything you need to find and fix idle problems is in there.

The first two posts contain all the updates to the fixes. 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.