1991 Ford Bronco Running rich

1991 FORD BRONCO
112,000 MILES • V8 • 4WD • AUTOMATIC
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NICKOLYN1
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My Bronco just had a major tune up consisting of:
spark plugs,wires,dist. cap, rotor,fuel pump,fuel filter,fuel injectors,fuel pressure reg.,map sensor, ignition control module,coil,IAC. It just about had all emmision stuff changed out. Even changed out the dist. Doubled checked the timing. Now my bronco is running rich with black smoke coming out of the exhaust. Its acting like the fuel filter is clogged. Can't give it throttle when under a load its bogging down. In neutral it revs up fine. I'm not sure what is going on. I don't have a CAT converter,due to long tube headers and don't have a O2 sensor either. It ran fine befroe but now I'm clueless on what is wrong.
Dec 25, 2008 at 9:29 AM
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BUDDYCRAIGG
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wow.
that was a lot of things to replace all at once.
if you paid a shop to do it. take it back to them and tell them to fix it.

if you did it yourself.
hummm.
well why did you replace so much stuff?
a tune up at the most would be
spark plugs,wires,dist. cap, rotor,fuel filter
you missed the air filter, oil change, tranny fluid change, coolant change.

unless there is a problem you should not have needed to touch these items that you changed.
fuel pump,fuel injectors,fuel pressure reg.,map sensor, ignition control module,coil,IAC, distributor.

if you had a clogged fuel filter, it would be running lean, not rich.

if you brought this truck to me as it is. these are the things i would check in this order.

spark plug wire order.
timing
load balance test

good luck
Dec 25, 2008 at 9:55 PM
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BUDDYCRAIGG
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sent via PM
[quote:6f29a833c6="nickolyn1"]I had a vacuum leak. My idle was surging. So I decided to pull the plenum and intake off. I did check the timing after all work was done. I had all new parts laying around so decided to change them out. When starting vehicle and let warm up and when I stop it, it will not start right away. Have to let sit for an hour before it will start again. Could the water in fuel done something to my heads? Did not do a compression check yet. Forgot to mention that my plugs are new but carboned up after a short stroll around the neighborhood. What is this saying that I cannot seem to understand?[/quote:6f29a833c6]

What does a fuel pressure test show?
you replaced the regulator, hopefully it's just letting too much fuel pressure to the injectors.

are the replacement injectors the correct type?
nothing that would let more fuel get into the combustion chamber right?
Dec 26, 2008 at 4:43 PM
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NICKOLYN1
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Stiil have the same issue. No power under load and to much fuel. Can you set timing if the timing chain has to much slack? I'm thinking now it might be timing problem. I can set the timing according to spec. 10deg. BTDC. What about any sensors I may have missed or not set after changing them out?
Feb 25, 2009 at 1:34 AM
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BUDDYCRAIGG
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have you tested anything?

and I'm surprised that you do not have a check engine light from the O2 sensor missing.
Mar 2, 2009 at 6:42 PM