black smoke, rough idle, stalling
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New User
Joined: Jan 2003
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black smoke, rough idle, stalling
my '91 V6 explorer is running rich, stalling and idling rough. I replaced plugs and plug wires, air filter and numerous sensors. The catalytic converter was even replaced but still, no luck. No check engine light comes on and the code scanner doesn't register any problems. Can anyone help me solve this quandry? Thanks!
Lead Driver
Joined: Nov 2002
Posts: 9,557
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From: Concord, NC
black smoke, rough idle, stalling
Check the fuel pressure regulator. It may have a hole in it allowing manifold vacuum to suck fuel into the intake bypassing the injectors, causing it to run rough.
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black smoke, rough idle, stalling
[updated:LAST EDITED ON 01-14-03 AT 00:52 AM (EST)]That sounds logical. I actually replaced my fuel pressure regulator a few months ago. How could this metal/alloy part have a hole in it? How do I test the part? If it does have a hole can it be plugged or does this expensive part need to be replaced?
Lead Driver
Joined: Nov 2002
Posts: 9,557
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From: Concord, NC
black smoke, rough idle, stalling
To test it, pull the vacuum hose off the back of it and if you have fuel in there, the internal diaphragm (rubber?) has a hole in it and is allowing manifold vacuum to suck fuel into the intake. If it's bad, it will need to be replaced. Check to see if it is warranted, especially if it is only a couple months old. I would start there, and also see if you can pull the codes (if any) that are stored in the computer.
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black smoke, rough idle, stalling
no fuel was visible. No codes when using scanner. I'm thinking either vacuum leak (but it wouldn't it run lean, not rich)or a leaking injector (rough cold but hot engine vaporizes excess gas maybe). What's the vacuum pressure supposed to read using a vacuum pressure guage? Same question for fuel pressure using related guage. Any other possibilities you can suggest would be appreciated. Thanks!
Posting Guru
Joined: Apr 2002
Posts: 1,471
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From: Greenwood In. USA
black smoke, rough idle, stalling
You said you changed plugs and wires. Have you double checked the connections? Checked the order? Also did you change the cap and rotor?
Vacumn on a good warm engine should be around 18-21" and steady
Gasman
Do you have Gas?
Propane Execeptional Energy
Vacumn on a good warm engine should be around 18-21" and steady
Gasman
Do you have Gas?
Propane Execeptional Energy
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