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nathaniel11
Member
Is anybody running straight av gas having trouble with it taking out your afr sensors or getting false readings?
Av gas with afr
- Thread starter nathaniel11
- Start date
The concerns with lead in regards to sensors is a longer term issue that is really practical to worry about in the life of a sled. Many of us have run thousands & thousands of miles without any issues. On my turbos I ran either av or leaded race fuel, and never had any sensor issues. They WILL go out on occasion, but IMO the lead concern is a non issue.
Never had any false readings I could contribute to it either.
Never had any false readings I could contribute to it either.
nate, if your running a straight UN muffled dump pipe you will get readings that will not reflect the true state of tune. too much fresh air gets to the sensor and makes it look rich ( cold) when in fact you are not..
Temp of the gasses drops instantly when entering the unresticted large OD of the dump pipe.
Temp of the gasses drops instantly when entering the unresticted large OD of the dump pipe.
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Spaarky
Well-known member
I will try to help him(nate) clarify a bit. The AFR readings bounce all over the place, AEM gauge, it will even go to the dashed lines. Typically on mine if it does that, pig rich. We really had not spent much time on it over the last year, so finally a couple weeks ago I stopped him. Time to get it figured out.. FINALLY. In the past he has just turned it down till it ran clean. The same way Twister taught me to do it.
So, I had him turn it down a quarter turn on the power jets. Couple runs ... 12.9. I have seen them read lean in the past when they were still rich, so lets turn it down another quarter. I have seen them go from 13's to 10-11 readings on a small turn. The next quarter turn went to 13.2. Ok, one more but be careful. It just read leaner. It got rid of the jumping around but was just lean. Appeared that way anyway. Tough to read wash on those Doo's.
He has something else going on too, or a combination of things. It doesn't idle the best so I was messing with it to set the idle. I was trying to get it to calm down and grabbed the choke. When I did, the motor raced. I am guessing he has a air leak somewhere? Also when he grabs the throttle, it sounds like he has some reeds going south. Need to check that.
Oh yeah, not done yet. His FPR, freezes up all the time. I have never seen anything like it. Take a heat gun to it and its fine all day. Leave it sit outside and the next morning its froze and the pressure is through the roof. I don't understand it. Only thing I could figure is he is getting some water in the fuel, but he has been to three different airports. Next would be condensation in the tank. I have seen that when it goes from warm to cold and back again. We tried to turn the FPR down to 3, but the lowest it would go is 3.5-4.
Its a Peak kit, the exhaust comes off the turbo and makes a long S and into the tunnel in front of the chain case. It could be that causing false readings. I have my Poo the same way, and mine reads dead nuts on. Checking wash. Only thing is he has 3" exhaust and mine is 2.5". Not sure if that would make a difference.
The whole thing just needs a little love. We need to go through everything. The kits needs to be upraded/updated in my opinion. I like the simplicity, but it needs a bigger charge tube and bigger turbo.. IMO.
So, I had him turn it down a quarter turn on the power jets. Couple runs ... 12.9. I have seen them read lean in the past when they were still rich, so lets turn it down another quarter. I have seen them go from 13's to 10-11 readings on a small turn. The next quarter turn went to 13.2. Ok, one more but be careful. It just read leaner. It got rid of the jumping around but was just lean. Appeared that way anyway. Tough to read wash on those Doo's.
He has something else going on too, or a combination of things. It doesn't idle the best so I was messing with it to set the idle. I was trying to get it to calm down and grabbed the choke. When I did, the motor raced. I am guessing he has a air leak somewhere? Also when he grabs the throttle, it sounds like he has some reeds going south. Need to check that.
Oh yeah, not done yet. His FPR, freezes up all the time. I have never seen anything like it. Take a heat gun to it and its fine all day. Leave it sit outside and the next morning its froze and the pressure is through the roof. I don't understand it. Only thing I could figure is he is getting some water in the fuel, but he has been to three different airports. Next would be condensation in the tank. I have seen that when it goes from warm to cold and back again. We tried to turn the FPR down to 3, but the lowest it would go is 3.5-4.
Its a Peak kit, the exhaust comes off the turbo and makes a long S and into the tunnel in front of the chain case. It could be that causing false readings. I have my Poo the same way, and mine reads dead nuts on. Checking wash. Only thing is he has 3" exhaust and mine is 2.5". Not sure if that would make a difference.
The whole thing just needs a little love. We need to go through everything. The kits needs to be upraded/updated in my opinion. I like the simplicity, but it needs a bigger charge tube and bigger turbo.. IMO.
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good job addict. nice when you have friends on boost to throw a hand in and cure the ills..
funny thing specific to a doo,,, when a mag side crank seal is going away or gone, they will have a sizable BOOST leak and a funky idle..they wiil NOT however burn down from the leak, they will if you keep chasing it thinking the lost power is in the tune,,good luck my friend. glad your helping.
funny thing specific to a doo,,, when a mag side crank seal is going away or gone, they will have a sizable BOOST leak and a funky idle..they wiil NOT however burn down from the leak, they will if you keep chasing it thinking the lost power is in the tune,,good luck my friend. glad your helping.
