surging idle again!!

[willys1]

I have a 93 lx with 34,000 original miles.It had a small surge ,about 100rpm's. The other day I installed a screamin demon ign.system,and it went away ,briefly,then it came back.then I replaced my fuel filter because of a pinging problem,the pinging stopped and so did the surge.The surge is back,,any Ideas what to do???

 

[firehart2]

In order to fix the problem correctly, you will need to go to ford and get the idle air adjuster plate. This will stop your surging idle. Ford has known about this for ever and issued this component as the "fix". When installing the plate, be sure to follow the instructions exactly and you shouldn't have any problems. The plate is only $17.00 or so, it is a "ford" part.

, Jodie

 

[TrophyHead]

I second buying the idle air adjuster plate. It goes in between your throttle body and IAC. Theres a screw on it so you can adjust the airflow. With only 34,000 miles I highly doubt its anything else. That part fixed surging idle on my 125,000 mile car. Get some fuel injector/carburator cleaner and spray a lot of it inside your IAC, It cant hurt anything. Just to get the carbon buildup off. The IAC is that cylinder looking thing on the front side of your T.B. I'm sure this will work but If not your TPS voltage could be out of whack another easy fix, but try the before mentioned first.

 

[HyPer-50]

#f2pe-9f939-aa thats the part # for the idle air adjuster please let me know if it works, I haven't tried it on mine yet, but going to as soon as I get done with everything else.

 

[willys1]

Im leaving for the dealer in 30 min. I'LL let you know how I make out.I'm putting on my new TB on at the same time.Accufab 65mm.

 

[86GT-Top]

let us know if that part fixes it. If it does, im off to the dealer!

 

[Black Sun 5.0]

If the idle air adjuster plate doesn't resolve the problem, I might recommend the fuel pressure be adjusted and giving the car a full tune-up. When I had my intake and TB installed, I developed a mad idle surge, to the point where the car would eventually stall out at idle. After much trial and error, I had an adjustable fuel pressure regulator installed and gave the car a full tune-up. I haven't had any surge since. Just a possible suggestion.

 

[jerry beach]

I got the idle adjuster plate, and it made no difference. Some have had good luck with it, so its a cheap shot at fixing it. Something nobody mentioned is cleaning the throttle body. Get some new gaskets, take it off and clean it really good, many times this will eliminate surge. I heard that ford decided it would save labor to install the adj. plate instead of cleaning the TB. If you remove it, you have to drain the coolant down some, dont want any of it down in you motor.

 

[noslow5_0]

im gonna subscribe to this cause i have tried everything in the book even the idle air adjuster.... the only sensors that are left to replace are the 02's and maf...

 

[MAC'n89Blckstng]

I think my car surges from 02 sensors, I have the idle screw set higher and the IAC is disconnected (surged up and down by 600 rpm and almost always stalled after a while when I let it idle). But it still surges when the weather gets warm. So Im gonna get a new IAC and 02's. Could the warm weather surging be that my MAF is bad? My car does have 193000 miles on it so anything could be a possibility.

 

[mustangdaren]

A little tweeking of the throttle blade position and the tps voltage can help a lot. I just installed a new intake and the car was sluggish and would not idle worth a crap. The fix was two turns of the throttle plate screw and setting the tps voltage from 1.021 volts to .987 volts. It now idles perfect. I never notice as much differece with the tps voltage when the car was N/A but with the supercharger it made a world of difference adjusting it. Another thing you might want to check is the vacuum lines under the intake. They can become dry rotted over time. I found a rubber cap broke off under my GT40 intake when I removed it. Who knows how long it has been that way but it was a 3/8 barbed fitting which most definitely was causing loss of vacuum and boost.

 

[willys1]

let us know if that part fixes it. If it does, im off to the dealer!

I went to Hackettstown Ford,,ordered the part,it will be in tomorrow morning! 21 beans. Im putting on my new accufab TB first,,I have a feeling that might do it.If not, I got the part!!

 

[grippper]

i agree with jerry. clean the throttlebody real good. replace gaskets. and o2 sensors.

 

[willys1]

I dont have to clean it,Im putting a brand new one on with new gaskets.If thats the problem,I waisted 21 bucks.I'LL find out tomorrow!!

 

[willys1]

Put in the accufab.It whistles!!! It still surges ,,guess I"'LL put that part in Monday!

 

[88GTStreetRod]

When I was having the same problems you were, clocking the mass air was only part of the fix. I pulled out my computer and found out that it was a cobra computer (X3Z) and that there was a custom chip in it. I pulled the chip out and the car ran great. Have you looked at your computer?

Put in the accufab.It whistles!!! It still surges ,,guess I"'LL put that part in Monday!

 

[willys1]

When I was having the same problems you were, clocking the mass air was only part of the fix. I pulled out my computer and found out that it was a cobra computer (X3Z) and that there was a custom chip in it. I pulled the chip out and the car ran great. Have you looked at your computer?

Actually no,where is the computer?? How did you know it was a custom chip?

 

[noslow5_0]

i just found out today that the sensor on the lower intake which is suppose to measure the temp. of the air can cause a surge.... I just snapped a bolt of inside my lower intake when i went to replace the gaskets between the head/lower intake. So i cant vouch for this working if it is replaced....once i get mine back together im gonna go buy a new sensor and see if it fix's it at all cause mine keeps gettin worse to the point were i pull up at a light it dies...

 

[TrophyHead]

Actually no,where is the computer?? How did you know it was a custom chip?

Its under the plastic kick panel on the passenger's side. After you install the plate and if that dosnt fix it, adjust your TPS. Did you clean your IAC valve do that when you put the plate on. Get some carb cleaner and use a lot try to get it spotless with no carbon build up left inside.

 

[GMstomper]

If your idol is surging try pumping your brakes quikly. If it levels out as long as you're pumping the brakes then its time to start checking hoses. Because you my friend have a vacuum leak.