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FAST EZ 1.0 fouling plugs & O2 sensor

 
Old 10-07-2018, 01:21 AM
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MN80Vette
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Default FAST EZ 1.0 fouling plugs & O2 sensor

I installed a FAST EZ TBI EFI system 3 1/2 years ago that recently started fouling a set of spark plugs in ~50 miles and O2 sensors in ~100 miles, and it deposits black soot on the driveway or garage floor. This is happening AFTER I replaced the entire ignition including a MSD digital ignition with rev limiter (#83647) that provides a clean tach signal to the FAST EZ ECU, HEI coil, cap, rotor, and spark plugs. A couple of the plugs have less soot on them than all the other plugs.

I have a Walbro in-tank fuel pump that is not controlled by a separate fuel pump relay, not the FAST ECU, and the regulator is set to 43-45 psi with the engine turned off. The dual radiator fans are controlled by dual Ron Francis fan controls, not the FAST ECU.
The FAST ECU is mounted on the back of the passenger side wheel well ahead of the fender louver (30" from the distributor, 6" further than the recommended 24").
The handheld cable is routed through the firewall near the top of the passenger footwell. I don't have AC in my car, so that function of the ECU is not used.
I reset the ECU to the base tune after replacing the O2 sensor and ignition.

The engine ran GREAT with a new O2 sensor and all new ignition, but it started missing after about 30 miles and got progressively worse. The AF and TAF were pretty close until the O2 sensor system error came on at about 100 miles after being replaced.

I am wondering if one of the sensors can be bad and causing the degradation after new parts installed and the rapid soot buildup and spewing from the mufflers. If so, which sensor?




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Old 10-07-2018, 06:23 AM
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Originally Posted by MN80Vette View Post
I installed a FAST EZ TBI EFI system 3 1/2 years ago that recently started fouling a set of spark plugs in ~50 miles and O2 sensors in ~100 miles, and it deposits black soot on the driveway or garage floor. This is happening AFTER I replaced the entire ignition including a MSD digital ignition with rev limiter (#83647) that provides a clean tach signal to the FAST EZ ECU, HEI coil, cap, rotor, and spark plugs. A couple of the plugs have less soot on them than all the other plugs.

I have a Walbro in-tank fuel pump that is not controlled by a separate fuel pump relay, not the FAST ECU, and the regulator is set to 43-45 psi with the engine turned off. The dual radiator fans are controlled by dual Ron Francis fan controls, not the FAST ECU.
The FAST ECU is mounted on the back of the passenger side wheel well ahead of the fender louver (30" from the distributor, 6" further than the recommended 24").
The handheld cable is routed through the firewall near the top of the passenger footwell. I don't have AC in my car, so that function of the ECU is not used.
I reset the ECU to the base tune after replacing the O2 sensor and ignition.

The engine ran GREAT with a new O2 sensor and all new ignition, but it started missing after about 30 miles and got progressively worse. The AF and TAF were pretty close until the O2 sensor system error came on at about 100 miles after being replaced.

I am wondering if one of the sensors can be bad and causing the degradation after new parts installed and the rapid soot buildup and spewing from the mufflers. If so, which sensor?





Been down this road... its not your EZ EFI, you are sucking oil through the rocker studs or from the oil valley being sucked between the intake and heads...
See the oil on the threads? ...

Last edited by pauldana; 10-07-2018 at 06:26 AM.
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Old 10-07-2018, 08:58 AM
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Originally Posted by pauldana View Post
Been down this road... its not your EZ EFI, you are sucking oil through the rocker studs or from the oil valley being sucked between the intake and heads...
See the oil on the threads? ...
Oh snap. That's a lot worse than a bad sensor. Now I notice that the spark plug with little fouling does not have oil on the threads. Here is a picture of 4 spark plugs. The oil on the threads is obvious.

I also attached a picture I took before I installed the Edelbrock RPM Air Gap. How can oil get sucked from between the intake and heads?

Do you know what caused this problem in your car? What did you do to fix it?







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Old 10-07-2018, 09:55 AM
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ok.... its 1 of 2 things here.

1. the rocker arm studs were put in with out proper thread seal, thus every intake rocker will have to be removed, thread seal (use AFR thread seal) will have to be put on then reinstalled.

2. the gasket between the heads and the intake are not sealing,,, you may need a thicker gasket as your geometry my be off ... use correct RTV also on both sided of the gasket.


Until this problem is fixed your EZ EFI will never function properly.

p
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Old 10-07-2018, 01:30 PM
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Originally Posted by pauldana View Post
ok.... its 1 of 2 things here.

1. the rocker arm studs were put in with out proper thread seal, thus every intake rocker will have to be removed, thread seal (use AFR thread seal) will have to be put on then reinstalled.

2. the gasket between the heads and the intake are not sealing,,, you may need a thicker gasket as your geometry my be off ... use correct RTV also on both sided of the gasket.


Until this problem is fixed your EZ EFI will never function properly.

p
My engine is a GM Performance 350 HO crate, and GM built Gen 1 small block engines for decades. I searched online and didn't find ANY mention of leaky rocker studs on GM Performance crate engines.

On the other hand, I installed the FAST EZ EFI and Edelbrock RPM Air Gap intake in my garage. It was my first and only such project.

The gasket between the heads and the intake not sealing is the safe bet.

Thank you for your prompt reply to my post!



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Old 10-07-2018, 02:56 PM
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how you will tell if it works

1. you will no longer burn oil
2. you will not have backfire "pops" on deceleration
3. you will not blow smoke after deceleration then hit throttle
4. the engine will be much smoother and will not have noticeable more vibration above 3500
5. will idle better
6. the plugs after 300 miles will show no black

points:

1. after fixed, it will take your EFI 100-300 miles to resell learn.
2. run your car for 30-60 sec at 1000, 1500, 2000, 2500, 3000, 3500, 4000, 4500, 5000.... in gear driving steady without moving peddle
3. full throttle 3 times from 25% throttle ~ 30-80mph
4. same as above backwards
5. re-adjust IAC and throttle blades
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Old 10-08-2018, 07:35 AM
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Could be too much fuel pressure. Injectors are opening correct number of milliseconds but too much fuel comes out in that amount of time causing rich condition.
Burning oil would look like white fluffy stuff on the plugs. Gasket leaks cause un metered air so lean condition. Your plugs look like rich condition.

I would guess fuel pressure regulator failing or fuel line from engine back to tank restricted.
If you have a returnless pump check control wiring.

Last edited by Greengear; 10-08-2018 at 07:42 AM.
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Old 10-08-2018, 09:33 AM
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No
it is what I told him
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Old 10-08-2018, 10:10 AM
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Looks like the root cause is lack of oil control like pauldana says. The oil causes misfiring which adds oxygen to the exhaust and makes the O2 sensor read lean. EFI adds fuel to compensate which makes the plugs both oily and sooty. Fixing the oil control issue will also fix the bad air/fuel ratio.
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Old 10-08-2018, 10:57 AM
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Originally Posted by zwede View Post
Looks like the root cause is lack of oil control like pauldana says. The oil causes misfiring which adds oxygen to the exhaust and makes the O2 sensor read lean. EFI adds fuel to compensate which makes the plugs both oily and sooty. Fixing the oil control issue will also fix the bad air/fuel ratio.
^^^^^^^^^^^Yes, This^^^^^^^^^^^^^




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Old 10-29-2018, 09:03 AM
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Originally Posted by pauldana View Post
No
it is what I told him
Originally Posted by zwede View Post
Looks like the root cause is lack of oil control like pauldana says. The oil causes misfiring which adds oxygen to the exhaust and makes the O2 sensor read lean. EFI adds fuel to compensate which makes the plugs both oily and sooty. Fixing the oil control issue will also fix the bad air/fuel ratio.
Yes, fixing the intake gasket leak fixed the problem main problem as the picture of a before-fix spark plug and after-fix (and 280 miles) spark plus show:



The O2 sensor still fouls though. My theory is that there was a LOT of carbon build-up in the cylinders and headers that is still being blown out now.




With Live Data displayed, the O2 indicator is checked and the SE is clear (not checked), but when I start from a stop, the SE (Wideband O2) comes on and the car bucks violently until I let up on the gas. The O2 indicator stays checked, "This indicates the sensor is warmed up
and functioning." Once I get going and clear the SE/Wideband O2 error, the car runs perfectly...for a while. After a while and a few miles on the highway, I feel the engine studder and the SE/Wideband O2 error returns but the engine still seems to run well. I can clear the error and it SE stays clear for a while and a few miles before the SE error returns.

If I stop and clear the error, it idles perfectly, the O2 indicator stays checked, and the SE error stays cleared UNTIL I start to get under way. That's when the SE/Wideband O2 error gets set and the car bucks violently again. If I baby the pedal right, I can accelerate but the engine continues to momentarily cut out repeatedly. That's what causes the bucking. The Live Data display can't keep up to the large and rapid changes, so I can't tell you what the AF ratio is doing. I have several O2 sensors, and the problem is the same for each. I ordered another one.

Can carbon build-up from the intake gasket leak be causing the O2 sensor fouling and SE now (after 280 miles)? Or is there something else I should check?
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Old 10-29-2018, 09:22 AM
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O2 is not getting power to heat
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Old 10-29-2018, 10:58 AM
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That makes sense. I just found instructions for testing that problelm:
"Does your O2 sensor heat up now? If it does not you need to troubleshoot the wiring to find out why. With the key on you should see 12V on pin 3 of the 6-pin O2 connector (orange wire) to vehicle ground. If you see 12V, measure between pin 3 and pin 4 of the O2 connector. Pin 4 is the O2 sensor heater ground (white wire).
You should see 12v. If you do not see 12V go to the Schematics in the Help file and use the schematic to trace the wiring back through the harness to the ECU to find the problem."

I will test the wiring tonight and post results here so others might benefit too.

Thank you!
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Old 10-29-2018, 11:05 AM
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Don't know how good the WBO2 diagnostics are on your system. I can see two possibilities:

1) Heater not getting power.
2) Heater is powered but sensor is overheating. I had this happen with the sensor in the collector. Would work for a while and then throw an overheat code. I fixed it by sandwiching a 4"x8" copper sheet between sensor bung and sensor. This reflected enough heat to where it worked.
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Old 10-29-2018, 11:30 AM
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Originally Posted by zwede View Post
Don't know how good the WBO2 diagnostics are on your system. I can see two possibilities:

1) Heater not getting power.
2) Heater is powered but sensor is overheating. I had this happen with the sensor in the collector. Would work for a while and then throw an overheat code. I fixed it by sandwiching a 4"x8" copper sheet between sensor bung and sensor. This reflected enough heat to where it worked.
The O2 sensor is a few inches behind the collector in the passenger side pipe. Overheating might still be a problem that close to the collector. I will start by chasing #1. If the voltage is good, then #2 could very well be the problem. How do you know if the O2 error is caused by an overheat code? If that's the problem, then I will try your solution for #2.
Thank you!!
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Old 10-29-2018, 12:39 PM
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Don't know if FAST distinguishes between error codes. The WBO2 I had the overheating problem with was from Innovate and it showed a code on the display.
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Old 10-29-2018, 12:42 PM
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Originally Posted by MN80Vette View Post
The O2 sensor is a few inches behind the collector in the passenger side pipe. Overheating might still be a problem that close to the collector. I will start by chasing #1. If the voltage is good, then #2 could very well be the problem. How do you know if the O2 error is caused by an overheat code? If that's the problem, then I will try your solution for #2.
Thank you!!

The O2 sensor NEEDS to be hot and should be in the collector.

Last edited by pauldana; 10-29-2018 at 12:42 PM.
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Old 10-29-2018, 01:19 PM
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Old 10-29-2018, 02:23 PM
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Originally Posted by pauldana View Post
The O2 sensor NEEDS to be hot and should be in the collector.
True for a narrow band O2 sensor, not true for a wide band. A WBO2 is fine running on nothing but its built-in heater. Too much exhaust heat will overheat it and give bad readings.

This is from Innovate which throws Error 8 when this happens:


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Old 10-29-2018, 03:01 PM
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Originally Posted by zwede View Post
True for a narrow band O2 sensor, not true for a wide band. A WBO2 is fine running on nothing but its built-in heater. Too much exhaust heat will overheat it and give bad readings.

This is from Innovate which throws Error 8 when this happens:


I remember having this conversation with FAST about a year ago... the lead tech, forgot his name, told me the best place for there O2 to be was at the collector.
Remember... The above is for a more factory system with a cast ram exhaust manifold and 1-2" pipe. The exhaust gasses in this setup stay much hotter all the way out.

Us/me on the other hand, run 1 7/8" ceramic coated headers with 3" free flowing mandrel bend exhaust with X-pipe,,, thus the heat is dissipated more quickly///

Thus the bung on the collector.
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