I sometimes have a bit of a rough idle and a small hesitation from idle to off idle on the car above. Car is all stock except for a Flowmaster cat back system, and K&N air filter in the stock housing.
So far I have cleaned the air filter, and ran some Techroline (Chevron gas to clean the injectors). Tomorrow I will change the fuel filter. IF that doesn't work, I have been told that the IAC's sometime get dirty or go bad. Should I be looking at it for the next step? I just bought the car about 10 days ago. Car has 34,000 original miles to date. Any other suggestions would be great. Thanks in advance...
Frank
On edit: Talked to a couple of guys that say that the hesitation is normal to these cars. Sure doesn't seem right. The small bit of rough idle doesn't bother me, but the hesitation does.
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1993 Cobra teal, leather, Kenne Bell 2,1L @ 8psi, 90mm LMAF, 42# injectors, TwEECer RT, Hurst Billet SST Shifter, Max Motorsports Full Length sub frame connectors & K-member brace, 75mm Accufab throttle body.
did you try cleaning the iac sol and throttle body with a tooth brush and chemtool? throttle body, do it with engine cold so if drips on exhaust wont catch on fire, engine off, spray inside throttle body ,throttle plate open and brush till clean,wipeing off excess cleaner, also use crc electrical contact cleaner to clean maf meter sensor wires, a couple of shots of this on the sensor wires inside the tube that the air flows over, do not, i repeat do not touch or brush those sensor wires, let air dry, let me know, big G
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93 LX, 5.0, aod 3.73,bbk shortie headers, x pipe, pypes 2 1/2" all mandrell bent , carbon fiber driveshaft,70mm throttle body,73mm c&l meter, 24lb hr injectors,b303 cam, crane cobra 1.7 r rockers, electric fan, 6g alt,underdrive pullies,00 gt wheels 17x8 1/4 mile time 12.85. @ 108.96 mph .100% italian
I think that I would check the voltage on the TPS before doing anything else. The voltage with ignition on and engine off should read 0.95 to 0.99 volts. The voltage can be adjusted by loosening the screws on the TPS and turning it slightly clockwise or counter-clockwise until the proper voltage is reached. After adjusting the engine off voltage you should check the voltage with ignition on and engine running at idle which should be 1.05 +/-. If that doesn't solve the problem then I would remove and clean the IAC.
i agree with snake. the reason i do is because 34k miles seems a little soon for a IAC solenoid to start acting up. they should go a lot longer than that before you need to clean or replace them. second the hesitation sounds like your EGR system acting up you might want to check that as well
a contaminated maf sensor hot wire from the oil mist of a k&n filter will cause a hisitation because it will cause a lean run condition, have had success by doing this, big G
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93 LX, 5.0, aod 3.73,bbk shortie headers, x pipe, pypes 2 1/2" all mandrell bent , carbon fiber driveshaft,70mm throttle body,73mm c&l meter, 24lb hr injectors,b303 cam, crane cobra 1.7 r rockers, electric fan, 6g alt,underdrive pullies,00 gt wheels 17x8 1/4 mile time 12.85. @ 108.96 mph .100% italian
Thanks for the info guys. I'll look into all of that now that I have a decient manual. I'm not really in tune with the injected engines as I'm pretty much an 'ol school guy. Only because I haven't untill two weeks ago, have a gas engine that was injected.
Frank
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1993 Cobra teal, leather, Kenne Bell 2,1L @ 8psi, 90mm LMAF, 42# injectors, TwEECer RT, Hurst Billet SST Shifter, Max Motorsports Full Length sub frame connectors & K-member brace, 75mm Accufab throttle body.
Okay, I pulled the MAF and cleaned it with CRC MAF cleaner. It didn't apear to be dirty at all, but I sprayed it anyway. Looked at the Throttle body and it looked clea alos, until I opened the throttle plate and seen some black soot behind the plate. Wiped it out as best as I could using a rag with some cleaner. Looked much better than before. Put it all together and it is the same. It is deffenetly an off idle problem. IF I hit the throttle hard from an idle (in neutral) it will actually knock. If it's just above idle, it doesn't do this. Any other ideas???
Frank
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1993 Cobra teal, leather, Kenne Bell 2,1L @ 8psi, 90mm LMAF, 42# injectors, TwEECer RT, Hurst Billet SST Shifter, Max Motorsports Full Length sub frame connectors & K-member brace, 75mm Accufab throttle body.
not a mustang but,my ranger had a hesitation ,worse when cold and if you lugged it it would miss and ping, i did a "b g" injector clean at work and it fixed it? you disconnect the fuel lines and add a pressurized bottle with this injector cleaner in it and start engine, let it idle in about 5 min. it will die or the cleaner runs low making it run rough or ping,and knock then turn it off, reconnect lines, i work at a ford dealer ,i dont really believe in all that snake oil but it did work, big G
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93 LX, 5.0, aod 3.73,bbk shortie headers, x pipe, pypes 2 1/2" all mandrell bent , carbon fiber driveshaft,70mm throttle body,73mm c&l meter, 24lb hr injectors,b303 cam, crane cobra 1.7 r rockers, electric fan, 6g alt,underdrive pullies,00 gt wheels 17x8 1/4 mile time 12.85. @ 108.96 mph .100% italian
not a mustang but,my ranger had a hesitation ,worse when cold and if you lugged it it would miss and ping, i did a "b g" injector clean at work and it fixed it? you disconnect the fuel lines and add a pressurized bottle with this injector cleaner in it and start engine, let it idle in about 5 min. it will die or the cleaner runs low making it run rough or ping,and knock then turn it off, reconnect lines, i work at a ford dealer ,i dont really believe in all that snake oil but it did work, big G
Hmmm, never heard of it. Where did you get itl
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1993 Cobra teal, leather, Kenne Bell 2,1L @ 8psi, 90mm LMAF, 42# injectors, TwEECer RT, Hurst Billet SST Shifter, Max Motorsports Full Length sub frame connectors & K-member brace, 75mm Accufab throttle body.
Bad IAC on 1993 Cobra? 
