95 GT doesn't want to idle

[94fordmustanggt]

I was doing some work on my buddy's car for him since he's over in Iraq and won't be home for a few more months. His dad brought his car to my house and it seemed to be running fine- he left it idling in my driveway for a minute. I dont know a whole lot about his car but I know engine mods include F cam, Edelbrock heads, Trickflow intake, 24 lb injectors, bigger MAF, TB, CAI, MSD6A and blaster coil, shorty headers, etc. The car doesn't sound like it has been tuned. I started it up to move it 10 feet forward in my driveway and stalled it. After that I tried to start it and it wouldn't start unless my foot was on the gas keeping it running. It was also surging pretty badly. I d/c'd the battery for a while and charged it up all the way. Reconnected it and it does a little better with the surging but still will not idle. If you take your foot off the gas it will die. I can keep it idling around 800 with my foot on the gas. Check engine light is not coming on. Couldn't find a vacuum leak.

 

[UTGAMER]

I had similar problem and this fixed mine, so it wont hurt to try

1. Turn key to ON (not start) position
2. Press gas pedal to floor(feel little button go click) Although no click for me
3. Hold for 5 seconds
4. Keep pedal to floor and turn key to off
5. Release gas pedal
6. Wait 2 minutes and then start car.

Let us know

 

[Bad2thebone]

I have a 94 mustang with the same cam , World sr. Heads, trick flow upper - lower intake, 75mm tb, 24lb injectors, custom mass air, msd streetfire ignition, summit distributor, msd coil, ford racing 9mm wires, and lots of other stuff and i had the same problem. My major problem was on the throttle body adapter , i forgot to block off the egr plate. You have a much more minor problem. the f cam alone has a very rough idle and sounds like its about to die when it idles. I would adjust the idle with the flathead screw right above the idle air control valve. If that doesn't work check and make sure that the timing is set correctly. i found mine likes about 6-8 degrees advanced. If you still have a problem it will more than likely be a small vacuum leak.

 

[BlackVert]

with mods like that and no tune, our cars often have problems like what you are describing ... sometimes they will start up better when cold than hot. others are the opposite ... starts up better hot than cold. if you keep your foot off the gas pedal, the rpms go up and down and it eventually dies (aka the searching or surging idle problem). it has to do with the tune and the first 30-60 seconds where it gives more fuel than normal because it just started up. usually, if you can keep it running (with the gas pedal) for 30-60 seconds, then the idle calms down and it is happier. another way to make it idle better is to drive it for about the same amount of time (30-60 seconds). or you can do what bad2thebone says and increase the idle speed by opening the throttle with the adjustment screw a little.

but don't worry ... you didn't do anything to cause it.

 

[94fordmustanggt]

Thanks for the help guys. Found that the IAC sensor wasn't making a good connection and the harness clip was broken. Cleaned it and wrapped it with electrical tape to hold it tight- good to go.