Vacuum leak

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Jul 20, 2015 | 08:57 PM

JoeS.

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Vacuum leak

I have a V-10 in my Y2K F-250. Under the throttle body there is an elbow on a vacuum line that is badly cracked. I went to parts store and bought a heater line that fit both ends (different sizes) but isnt the exact angle of the original. It fixed the hissing vacuum leak but now it is running pretty rough. Doesnt seem to be pinched but it's definitely different. The poor performance during acceleration wasnt a problem before but is very noticeable now. Could the line being different effect the performance?

Laser pointer is touching the bad elbow in this pic.

Jul 20, 2015 | 08:59 PM

JoeS.

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I have the bettery disconnected now trying to let the computer reset so the check engine light goes off. Hoping that maybe the computer is still trying to compensate for the vacuum leak that isnt there anymore. And hoping that when reset it will level out.

Jul 20, 2015 | 09:01 PM

projectSHO89

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From: St Louis

You still have a vacuum leak, perhaps a new one from working around the old tubing.

Make sure you check that PCV hose elbow all the way back in the back.

Jul 20, 2015 | 09:14 PM

JoeS.

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Will do. Check engine light is off but it's still running rough. And now there is an odor almost like an exhaust wihen the cat is getting full. Kind of a sulfur-ish smell.

Jul 21, 2015 | 05:57 AM

projectSHO89

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From: St Louis

That indicates excessive unburned fuel is getting dumped into the exhaust. Usually caused by either a 1) vacuum leak or 2) misfire or 3) leaky injector(s).

Jul 21, 2015 | 06:34 AM

JoeS.

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Thanks! I'll check the PCV. A buddy told me last night to use a temp scanner to see if there's a large difference on either side of the cat and that may indicate a clog.

Jul 22, 2015 | 03:07 PM

JoeS.

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Vacuum leak and a bad boot ended up being the problem. I believe i'm going to put a high flow pipe, er, cat and maybe a muffler of some sort on it next.

Are yall seeing any benefit from putting a program on your early V-10's?