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  Topic Review (Newest First)
January 16th, 2014 04:39 PM
TG4 I had a similar idle issue with my car. It could be a sticky throttle plate or a dirty TPS sensor. My instructor suggested I first clean my throttle body with throttle / carb body cleaner and a toothbrush and scrub the whole inside. After than spray the body with a good amount of cleaner, get it on all sensors, etc, and start the car with the throttle to the floor, after it smooths out (it will be very rough for 30 seconds or so) rev the motor a bit. If your throttle body was filthy like mine you will spray a good amount of soot out the exhaust when you first start up.

That cleared up my issue for the most part, I don't think I could get it any better without taking it out and soaking it in a chemical bath.

A can of cleaner costs $3 and a toothbrush is often free so its worth a try.

BTW check key on engine off fuel pressure, it should be I believe about 35-37psi (I may be wrong). If the pressure is good look into doing a Fuel Pump Volume test.

Is your car exhibiting any signs of a bad or aging pump, such as the motor takes longer than about 1 crank to start, but if you turn the key on wait 5 seconds, recycle key, wait, then start the car, it fires right up?
January 16th, 2014 03:30 PM
Originally Posted by OHC230 View Post
25-28 PSI is definitely on the low side of things for sure. It might be time for a new fuel pump. I would suggest a V-8 pump when you replace yours as a minimum.
I always thought they were the same between the 2.3L and 5.0L. Do you have any idea what the flow rate is for the 2.3l compared to the 5.0l?
January 16th, 2014 09:30 AM
vristang Isn't 40psi with vac off per spec?

With iac replacement, recommend a base idle reset...
Summarized/Corrected Base Idle Reset Procedure

What is the manifold vac?
January 16th, 2014 06:46 AM
CGStangfan You should definitely check your throttle position sensor. It's on the throttle body below the idle air control valve towards the firewall. These 4 bangers were prone to this issue. It's getting harder and harder to find a good replacement TPS. Motorcraft doesn't make them anymore and Standard just stopped making them. I'm going to try an Echlin brand TPS and see how it does since I'm having the same issue on my 88. I hope this helps.
January 16th, 2014 02:35 AM
OHC230 25-28 PSI is definitely on the low side of things for sure. It might be time for a new fuel pump. I would suggest a V-8 pump when you replace yours as a minimum.
January 15th, 2014 11:45 AM
ranger50toy Did you change ignition PIP in distributor?
January 14th, 2014 12:14 PM
89stang_2.3 It has a MAP sensor and ill clean that when i get off. What should i clean it with????
January 14th, 2014 07:56 AM
Smokestang88 Do ya have a mass air flow sensor on that? I'd check that to see if it's dirty then spray and clean that out

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January 14th, 2014 12:45 AM
Mustang 2.3 Idle issues HELP!!!!

Okay i got a 89 mustang 2.3 5 speed. The car has never gave me a problem before till now! Just a few weeks ago the car would die at idle. Once it got down to 1000 rpm it would start to surge and the idle would jump from 500 to 1000 then it would die. It would start up with no problem cold or hot. When i go to take off it would start to jump and then it would take off when i just punch. It would run and drive great once im out of 1st gear but when im driving and if im staying steady at just under 2000 i feel the car acting like its not getting enough air or fuel. I got it to my brothers house and pulled the code on it. Funny thing is that the check engine light has never came on. When i checked it the only codes that popped up was the IAC and EGR. Okay the next day i replaced both of them and its still doing the same thing. Checked the codes again and nothing came up then i checked the compression on each cyl and all of them are at 120 thats good!!!! So I replaced plugs, wires, cap, rotor, ignition coil, distributor, and the TFI. When i did all of that the car was running a little bit better but still acting up. Then i jump to the Vacuum line bought all new hoses and tree. Still acting up. Next i Checked the fuel pressure. At idle the pressure is at between 25 to 28 wen its suppose to be at 30 when its idling. I disconnect the hose from the FPR and the psi would jump to almost 40 with my finger on the hose either way. So i replaced the FPR. The fuel pressure is still the same. Its now holding a idle for a little bit but it still surging and dieing like before. When im at one red light and i go to take off it would just start to jump and carry on and once i just punch it in 1st gear it would clear up it would drive good (still doing like i said in the beginning below 2000) The next light it would take off fine. but still idle like S**t. Everything Ive done to it so far the car has inprove. What else can it be PLEASE HELP!!!

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