New member need help

beedy11

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06 gt 5 speed, recently picked the car up starts and drives great, only issue is when coming to a stop, the car starts rough idling and dies, will start back and is fine again while driving, note I've replaced fuel pump, filter, coils, plugs, and injectors, could it be the brake booster? Any help would be appreciated
 

stkjock

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Is the car stock?

5spd - you mean manual trans? all 05+ GTs are 5 spd manual or auto
 

stkjock

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Have you checked the MAF and TB for dirt?
 

beedy11

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I've not yet, but I have a new TB and MAF on the way, I was just thinking it might be a vacuum leak, and wondered if anyone else has delt with this, the car sat for a few years before I got it, and the guy got rid of it because of this problem, I've had it on the scanner, with light on, while driving, and it's saying its running lean
 

JC SSP

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Bottle of soapy water spray it around the intake... if engine revs go up you have a vacuum leak. You can do smoke test too, but you need specific equipment.

Also, run a diagnostic on the system for codes...
 

VBSTANG06

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You can check STFT/LTFT at idle with a scan tool just to see what the ECM is giving the engine. My car has +22 LTFT at idle w/CAI and LT headers (straight pipe). It idles well though it's just SUPER RICH. It will also give me a low idle when I hit the clutch to come to a stop and I hit the brakes with the clutch in. I tried to watch live stream data while it happened and my RPM went to about 745 (but normal idle for me is 800 RPM steady).
 

VBSTANG06

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I say my engine is rich because commanded lambda in OL is .85-.98 while the fuel trims are these values (I have a Dyno tune so idle for me will be different than idle for you) but lean codes (+fuels trims) could be fuel, air intake/vacuum or lack of it, and spark I don't know for sure but I would think if there was no spark the ECM would dump more fuel to the engine and show positive fuel trims.
 

eighty6gt

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Take the car to Ford. They'll be able to scan and repair it without just throwing parts at the problem (that are worse than the ones the car came with, aftermarket/replacement parts quality is shit.)
 

yote0

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YES this methods has been used for many years to find vacuum leaks.
I think he's talking about the soap water part. Gotta be something flammable like carb cleaner, etc. for that to work.
 

JC SSP

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No bro. Soapy water gets sucked into the vacuum and idle increases. It’s an old trick. I have done it many times.
 

yote0

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Never heard of this method either, but after doing a quick search, it is indeed a legit method. It appears the soapy water momentarily seals the leak thus allowing the idle to return to its normal RPM. I have always used flammable aerosols for this.
 

JC SSP

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Smoke test is the best but you need special equipment. I have been using this method for many many years. It works, at least for me it does. Lol
 

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