running rich
Thread Starter
Instructor
Joined: Apr 2008
Posts: 153
Likes: 7
From: Painesville Ohio
running rich
Started my 94 this morning and noticed the idle seemed rough, decided to drive it to see if it was my imagination or maybe just cold. I got about 200 ft. down the road and noticed the cloud of light colored smoke behind me and a strong smell of fuel (no coolant odor). Turned around and pulled in the garage and took my truck to work. Is it possible that my cylinders were so loaded with fuel it would cause the rough idle? Engine started right up and ran but was just rough. Haven't had time took look at it further as I had to get to work. I'm thinking I need a fuel pressure gauge and look in that direction. Any suggestions for tommorrow when I can look at it?
Burning Brakes
Joined: Feb 2009
Posts: 785
Likes: 3
From: Richmond Virginia
first thing I'd check would be...pull the vacuum line loose at the fuel pressure regulator...if there is fuel in the vacuum hose or dripping from the regulator nipple....regulator is bad. I may be way off base...could be many things, but that's where I'd start
Safety Car
Joined: Feb 2000
Posts: 3,771
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From: MANDEVILLE, LA La
Thread Starter
Instructor
Joined: Apr 2008
Posts: 153
Likes: 7
From: Painesville Ohio
Had a chance to look at the car for a few minutes. Started car for a short time and it is definitely fuel vapors out of the pipes and there is fuel dripping from the engine area pretty good. Nothing leaking from the top of the engine,(injectors, fuel rail, etc). Pulled the vacuum line from the regulator and it is dry. Gonna try to mow the lawn before it rains and jack it up this afternoon and take a look.
Race Director
Joined: Jun 2009
Posts: 10,428
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From: Southside of Western Norte Americano State of Confusion, ColoFornia
St. Jude '13
I have exactly the same problem. I bought an 85 as a project car. and this is what it does.. its running so rich there is black soot on the back bumper.. and no check engine codes, all of the normal suspects have been check/replaced by previous owner (about $3,000 worth of shotgun replacement technique prom/ecm injectors pressure regulator,O2 sensor etc, sigh I am sensing my "project" may be more long term than anticipated.) so I would be most curious what you discover.
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Thread Starter
Instructor
Joined: Apr 2008
Posts: 153
Likes: 7
From: Painesville Ohio
Fuel is blowing out exhaust manifold and dripping down to the cat on the drivers side. Is it possible I have an injector thats stuck open and filling a cylinder with fuel? if so, how do I test?
Thread Starter
Instructor
Joined: Apr 2008
Posts: 153
Likes: 7
From: Painesville Ohio
Definitely an injector. Fuel system not holding pressure. Pulled fuel rail and could see fuel leaking from left rear injector. Call FIC injectors (bought injectors 1 year ago from them) and they are sending me a replacement set. Great customer service!
Race Director
Joined: Apr 2003
Posts: 17,700
Likes: 1,667
From: moraga ca
I would also suspect injectors. Don't run it any more until you swap them out. Whatever it is, you can wash down your cylinder wall and ruin your cylinders/rings. Make sure you change your oil after you get it figured out.
Safety Car
Joined: Jan 2004
Posts: 3,759
Likes: 8
Is that done while the car is running, or after you shut it down?
Burning Brakes
Joined: Feb 2009
Posts: 785
Likes: 3
From: Richmond Virginia
I usually check right after I turn off the engine..if the regulator diaphragm is torn/ruptured...you'll see and/or smell fuel around the vacuum hose or regulator nipple. The danger IMO on a running engine is if the diaphragm has a large hole...fuel pressure could spray fuel onto a hot engine. I'd still suggest wrapping a rag around the regulator and hose....and use care when removing.
Melting Slicks
Joined: Feb 2005
Posts: 2,135
Likes: 0
From: Sebastian Florida
St. Jude Donor '06
Are you kidding me, there are 20 different things that can cause this problem.
Number 1 is the fuel pressure regular, also a non firing spark plug(s).
Do the research and find out the problem, to many people throw money at the problem, if it is the FI's Jon is the man.
Number 1 is the fuel pressure regular, also a non firing spark plug(s).
Do the research and find out the problem, to many people throw money at the problem, if it is the FI's Jon is the man.
Thread Starter
Instructor
Joined: Apr 2008
Posts: 153
Likes: 7
From: Painesville Ohio
I did research the problem, thats how I came up with the injector as the culprit. Waaaay too much fuel to be a non-firing spark plug.
If you read the thread I've already contacted Jon.
Team Owner
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