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Fuel Running Rich, White smoke

  • Thread starter Thread starter Tas_Jak
  • Start date Start date Jun 1, 2024
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Tas_Jak

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Hey guys, first time poster here so feel free to tell me what I'm doing wrong with my post,

But, anyway I bought my first fuel-injected fox a little bit ago and have been trying to get it to run, got it started, and now seems to be running very rich, has lots of aftermarket goodies as was previously a drag car so probably going to be a pain to diagnose. After starting it, white smoke out of the exhaust, smells of fuel, not coolant. Also after a quick tap of the throttle drops below where it idles and then revs back up. Attached videos of the smoke and rpm gauge. Ran KOER codes and got a bank lean code, so thinking either one of the O2 sensors isn't working? Lmk what yall think, trying to get onto summit point this summer. Thanks.

- Smoke out the exhaust

- rpm gauge
 

limp

wrap a little cheese around it and its a done
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You said it was a drag car?? The cam in it could have alot of overlap allowing unburnt fuel to pass at low RPM....
usually white smoke is water, blues is oil, and black is fuel...
 
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Tas_Jak

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limp said:
You said it was a drag car?? The cam in it could have alot of overlap allowing unburnt fuel to pass at low RPM....
usually white smoke is water, blues is oil, and black is fuel...
Click to expand...
Theres more smoke that comes out at higher rpm. Low rpm its barely noticeable, but when you get higher it smokes the whole street out.
 

Noobz347

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Have you noticed [any] coolant loss?
 

limp

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Tas_Jak said:
Theres more smoke that comes out at higher rpm. Low rpm its barely noticeable, but when you get higher it smokes the whole street out.
Click to expand...
Do you know what parts are in the engine??
 
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Tas_Jak

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Noobz347 said:
Have you noticed [any] coolant loss?
Click to expand...
No, I'm pretty sure its holding in all the coolant.
limp said:
Do you know what parts are in the engine??
Click to expand...
All I know as of right now, JPC upper intake, cobra rockers, aftermarket heads, don't know about pistons or cam
 
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Tas_Jak

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Tas_Jak said:
No, I'm pretty sure its holding in all the coolant.

All I know as of right now, JPC upper intake, cobra rockers, aftermarket heads, don't know about pistons or cam
Click to expand...
It also has a bunch of stuff deleted, like the evap system, and all the heating box and stuff.
 

Potomus Pete

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I would start with vacuum lines. Check all connections. Even electrical ones because somebody else was fooling with it.
 

AeroCoupe

lube between the nut and the face. I know my lubes
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Have you pulled the plugs and looked at them?
 

2000xp8

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What is a JPC upper intake?
I've been doing this a long time and i don't think i've ever heard of that intake.

With the correct meter and injectors for these cars they will run right most of the time (assuming no vac leaks or coolant and oil going missing)
What color are the injectors and what is the calibration on the meter?
Always the chance someone removed a supercharger and left oversized injectors on the car.
 
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Tas_Jak

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Plugs are wet and covered in soot, which confirms it’s running rich at least.
2000xp8 said:
What is a JPC upper intake?
I've been doing this a long time and i don't think i've ever heard of that intake.

With the correct meter and injectors for these cars they will run right most of the time (assuming no vac leaks or coolant and oil going missing)
What color are the injectors and what is the calibration on the meter?
Always the chance someone removed a supercharger and left oversized injectors on the car.
Click to expand...
The injectors are just the bosh 19 lb injectors, checked the part number online and bought the correct meter to go with it.
The JPC intake is a custom one that was hand welded by that company, don’t know a whole lot about it other than it’s a speed parts company.
 

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Noobz347

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Soot? That is a [lot] of oil in there.

Those plug are completely toast. BTW. Do they all look like that?
 
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Tas_Jak

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Noobz347 said:
Soot? That is a [lot] of oil in there.

Those plug are completely toast. BTW. Do they all look like that?
Click to expand...
Ive pulled 5 and yep, so I’m guessing they all look like it, brand new plugs too
 

Noobz347

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Man... That could be rings, valve seals, PCV system gushing oil...

Time for a compression and leak down test.
 

Noobz347

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Is the intake plenum soaked with oil?
 
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Tas_Jak

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Noobz347 said:
Is the intake plenum soaked with oil?
Click to expand...
Yep just took it off and was gonna post that it also has oil in it.
 
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Tas_Jak

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Oil everywhere
 

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Noobz347

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Ok... Do you happen to know if a high volume oil pump is installed?


Also.... Pull the PCV valve and grommet. Shake the valve and see if it still clicks.

Under the grommet, there should be a screen. Pull that too. You should be able to see daylight through it when you hold it up to the sun.

Once the screen is out.... Hold your tongue [just] right and get your peepers down that PCV hole and see if there's a shield still down there or if you can see all way down to cast aluminum.
 
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Tas_Jak

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PCV system has also been gone, you think there’s too much crankcase pressure and it’s going through the valves and into the intake?
 

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Tas_Jak

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Noobz347 said:
Ok... Do you happen to know if a high volume oil pump is installed?


Also.... Pull the PCV valve and grommet. Shake the valve and see if it still clicks.

Under the grommet, there should be a screen. Pull that too. You should be able to see daylight through it when you hold it up to the sun.

Once the screen is out.... Hold your tongue [just] right and get your peepers down that PCV hole and see if there's a shield still down there or if you can see all way down to cast aluminum.
Click to expand...
Just drained the oil, still close to 5 quarts in there but it does seem very runny.
 
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