How to stop running too rich
07-19-2011, 06:04 PM
#31
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Year: 1994
Model: Cherokee
Engine: 4.0 L/242 CID I-6 High Output MFI
On the valve cover, there is two plastic elbows and your oil fill cap. The two elbows are what helps your engine breathe, and they connect to the airbox in such a way that they only "breathe" filtered air.
07-19-2011, 06:09 PM
#32
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Year: 1990
Model: Cherokee
Engine: The venerable 4.0
Originally Posted by 94JeepCherokeeMan
On the valve cover, there is two plastic elbows and your oil fill cap. The two elbows are what helps your engine breathe, and they connect to the airbox in such a way that they only "breathe" filtered air.
07-19-2011, 07:42 PM
#33
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Year: 1989
Model: Cherokee
Engine: Inline 6, 4.0L
Rear line is still where it should be. Front line is just loose so I'll extend the line and run it to the snorkel tomorrow. Are those the only two lines that should be breathing? Intake and front valve cover line? Others have something they should be plugged in to?
07-20-2011, 12:47 AM
#35
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Year: 1990
Model: Cherokee
Engine: The venerable 4.0
Originally Posted by 94JeepCherokeeMan
Sorry about that, slick, I keep forgetting renix is different
07-20-2011, 10:10 AM
#36
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Year: 1994
Model: Cherokee
Engine: 4.0 L/242 CID I-6 High Output MFI
I know there's two that go to the airbox. One is def the front ccv, and the rear one probably goes to intake, and then a different one goes to the airbox. I just replaced both ccvs and grommets too.
07-20-2011, 10:11 AM
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Year: 1990
Model: Cherokee
Engine: The venerable 4.0
Originally Posted by 94JeepCherokeeMan
I know there's two that go to the airbox. One is def the front ccv, and the rear one probably goes to intake, and then a different one goes to the airbox. I just replaced both ccvs and grommets too.
07-20-2011, 12:23 PM
#39
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Let's just jury rig this and do it the sneaky way. Dump 10 ounces of Acetone in there and that'll lean you up.
07-20-2011, 08:01 PM
#40
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Year: 1989
Model: Cherokee
Engine: Inline 6, 4.0L
Well my excitement was short lived. Just went out and cranked the jeep after I messed with my snorkel a bit. Installed a piece that was to restricting to the air flow. Cranked it and let it run for 10-15 seconds then I gunned it a bit. When I really revved it up it BLEW black smoke. When it was at idle the exhaust was clear.
Took out the restrictive piece, no big deal. Intake was totally clear, repeated steps 1 and 2, still blew smoke. I mean heavy, it dyed the grass below the pipe black.
Is this just carbon buildup from the vacuum leak being present for so long, being blown out? If not, what's the problem?
Took out the restrictive piece, no big deal. Intake was totally clear, repeated steps 1 and 2, still blew smoke. I mean heavy, it dyed the grass below the pipe black.
Is this just carbon buildup from the vacuum leak being present for so long, being blown out? If not, what's the problem?
07-20-2011, 08:52 PM
#41
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Well my excitement was short lived. Just went out and cranked the jeep after I messed with my snorkel a bit. Installed a piece that was to restricting to the air flow. Cranked it and let it run for 10-15 seconds then I gunned it a bit. When I really revved it up it BLEW black smoke. When it was at idle the exhaust was clear.
Took out the restrictive piece, no big deal. Intake was totally clear, repeated steps 1 and 2, still blew smoke. I mean heavy, it dyed the grass below the pipe black.
Is this just carbon buildup from the vacuum leak being present for so long, being blown out? If not, what's the problem?
Took out the restrictive piece, no big deal. Intake was totally clear, repeated steps 1 and 2, still blew smoke. I mean heavy, it dyed the grass below the pipe black.
Is this just carbon buildup from the vacuum leak being present for so long, being blown out? If not, what's the problem?
I had your EXACT symptoms, and I'm here to tell you you have one hell of a vacuum leak. I had a hard time tracing it because I could never hear the damn thing. My cruise control diaphragm was stuck open a little. Whenever I gunned it driving down the road the car behind me got smoked out.
You definitely have a vacuum leak. The MAP is sensing the amount of air you have at the intake. The air is getting through to your manifold after the MAP, so you're actually getting more air into the cylinder(s). The 02 reads the lean conditions and dumps more fuel in to correct it. There's also a good possibility that you have a small exhaust leak so clean air is going right into the 02 sensor. Either at the collector on your exhaust manifold, or maybe your intake/exhaust bolts have loosened up. I've actually had that happen to me a few times. Seems like I can't drive this thing 400 miles without needing to retighten those damn bolts. The more engine vibration you have the more they work themselves out faster.
07-20-2011, 09:12 PM
#42
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Year: 1989
Model: Cherokee
Engine: Inline 6, 4.0L
Originally Posted by CoffeeCommando
Well my excitement was short lived. Just went out and cranked the jeep after I messed with my snorkel a bit. Installed a piece that was to restricting to the air flow. Cranked it and let it run for 10-15 seconds then I gunned it a bit. When I really revved it up it BLEW black smoke. When it was at idle the exhaust was clear.
Took out the restrictive piece, no big deal. Intake was totally clear, repeated steps 1 and 2, still blew smoke. I mean heavy, it dyed the grass below the pipe black.
Is this just carbon buildup from the vacuum leak being present for so long, being blown out? If not, what's the problem?
Took out the restrictive piece, no big deal. Intake was totally clear, repeated steps 1 and 2, still blew smoke. I mean heavy, it dyed the grass below the pipe black.
Is this just carbon buildup from the vacuum leak being present for so long, being blown out? If not, what's the problem?
I had your EXACT symptoms, and I'm here to tell you you have one hell of a vacuum leak. I had a hard time tracing it because I could never hear the damn thing. My cruise control diaphragm was stuck open a little. Whenever I gunned it driving down the road the car behind me got smoked out.
You definitely have a vacuum leak. The MAP is sensing the amount of air you have at the intake. The air is getting through to your manifold after the MAP, so you're actually getting more air into the cylinder(s). The 02 reads the lean conditions and dumps more fuel in to correct it. There's also a good possibility that you have a small exhaust leak so clean air is going right into the 02 sensor. Either at the collector on your exhaust manifold, or maybe your intake/exhaust bolts have loosened up. I've actually had that happen to me a few times. Seems like I can't drive this thing 400 miles without needing to retighten those damn bolts. The more engine vibration you have the more they work themselves out faster.