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one fast 98 mach-z
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Discussion Starter · #1 ·
Does anyone think a rich fuel mixture with a 600 sdi could cause a red glowing exhuast can at night? And if so why? 90% of the people say it is caused by a lean fuel to air mixture. But I am willing to listen to other reasons. thanks
 

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edlund said:
Does anyone think a rich fuel mixture with a 600 sdi could cause a red glowing exhuast can at night? And if so why? 90% of the people say it is caused by a lean fuel to air mixture. But I am willing to listen to other reasons. thanks

[snapback]726800[/snapback]​
This is what my dealer told me. At about 7000 rpm the engine runs very lean, the exhaust gas probe senses this and trys to lower the temps by adding more fuel. If you do not move the throttle any, the sled then runs way to rich, the fuel that isn't getting burnt in the engine burns in the can causing it to get too hot. So yes, it is actually a rich fuel mixture.
 

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WOT said:
edlund said:
Does anyone think a rich fuel mixture with a 600 sdi could cause a red glowing exhuast can at night? And if so why? 90% of the people say it is caused by a lean fuel to air mixture. But I am willing to listen to other reasons. thanks

[snapback]726800[/snapback]​
This is what my dealer told me. At about 7000 rpm the engine runs very lean, the exhaust gas probe senses this and trys to lower the temps by adding more fuel. If you do not move the throttle any, the sled then runs way to rich, the fuel that isn't getting burnt in the engine burns in the can causing it to get too hot. So yes, it is actually a rich fuel mixture.
[snapback]727270[/snapback]​
Check your exhaust can.It could be plugged.
 

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It has to be rich to be burning down stream... lean burns in the engine and melts pistons.. when rich, the left over fuel not burned, will burn in the pipe and the muffler if there is sufficent oxygen.

You can do this on an automobile too.. did this in an automotive research lab back in the beginning of emmison testing.. we were playing with one, two and three miss firing plugs on a V8 to see when we would have the whole exhaust system glowing cherry red.. and when it would catch the unflameable carpet and mastic on fire.. Lots of fuel and air going down the pipe and burns in the pipe/muffler.. can be exciting when the whole system is glowing cherry red.

I personally would say that the dealer who said the system added fuel and was was rich is correct.

Just maybe 90% of the people are non knowledgeable about this issue... Of course it is possible the other 10% of us are full of it too.. but I don't think so based on experience and learnings and reading. You have to have both fuel and oxygen to burn.. most firemen will can tell you that.. Lean burns up the combustion chamber (pistons goes first) Rich burns down stream if there is oxygen from somewhere..
 

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diabolic said:
dealer told me not to use 94 octane it has ethanol or something like that
94 burns to hot
[snapback]727555[/snapback]​
When ethanol is used as a means of octane boost the fuel actually burns cooler, but ethanol also carries oxygen which, when used in a high enough concentration can cause a lean condition creating the need to jet richer. Most all gasolines have ethanol or something similar as an additive, Its my understanding it doesnt need to be advertised at the pump unless it exceeds 10%.
 

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one fast 98 mach-z
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Discussion Starter · #8 ·
djm said:
It has to be rich to be burning down stream... lean burns in the engine and melts pistons.. when rich, the left over fuel not burned, will burn in the pipe and the muffler if there is sufficent oxygen.

You can do this on an automobile too.. did this in an automotive research lab back in the beginning of emmison testing.. we were playing with one, two and three miss firing plugs on a V8 to see when we would have the whole exhaust system glowing cherry red.. and when it would catch the unflameable carpet and mastic on fire.. Lots of fuel and air going down the pipe and burns in the pipe/muffler.. can be exciting when the whole system is glowing cherry red.

I personally would say that the dealer who said the system added fuel and was was rich is correct.

Just maybe 90% of the people are non knowledgeable about this issue... Of course it is possible the other 10% of us are full of it too.. but I don't think so based on experience and learnings and reading. You have to have both fuel and oxygen to burn.. most firemen will can tell you that.. Lean burns up the combustion chamber (pistons goes first) Rich burns down stream if there is oxygen from somewhere..
[snapback]727544[/snapback]​
You sound dam smart. I think you are correct. This is why my pistons have not melted being aluminum having a lower melting point than steel, which the can is made from. I think that if the pistons were as hot as the glowing red can that they would have melted by now.
 

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I'm not sure if the "blue flame" issue stems from the same problem or not. But if it does, this happens on non HO 800's, as well has the HO's and SDI 600 + 1000's.
My main concern with this issue right now is if I am doing engine damage or not.
I think I can regulate how often I get the motor into his condition for the most part, but not all the time.
For those of that have seen it, it don't look good. Makes you wonder if you are going to go up in flames like others have reported.
Would be nice of BRP to let us in on whats up though.
 

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one fast 98 mach-z
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Discussion Starter · #10 ·
miniz said:
I'm not sure if the "blue flame" issue stems from the same problem or not. But if it does, this happens on non HO 800's, as well has the HO's and SDI 600 + 1000's.
My main concern with this issue right now is if I am doing engine damage or not.
I think I can regulate how often I get the motor into his condition for the most part, but not all the time.
For those of that have seen it, it don't look good. Makes you wonder if you are going to go up in flames like others have reported.
Would be nice of BRP to let us in on whats up though.
[snapback]728497[/snapback]​
wouldn't it be nice if brp had a tech rep read these pages at doo talk, and when they find a real problem that many are having, actually reply to use owners of doo's. I would be willing to list my s-n so they could check that it is still under warranty.
 

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one fast 98 mach-z
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Discussion Starter · #11 ·
miniz said:
I'm not sure if the "blue flame" issue stems from the same problem or not. But if it does, this happens on non HO 800's, as well has the HO's and SDI 600 + 1000's.
My main concern with this issue right now is if I am doing engine damage or not.
I think I can regulate how often I get the motor into his condition for the most part, but not all the time.
For those of that have seen it, it don't look good. Makes you wonder if you are going to go up in flames like others have reported.
Would be nice of BRP to let us in on whats up though.
[snapback]728497[/snapback]​
wouldn't it be nice if brp had a tech rep read these pages at doo talk, and when they find a real problem that many are having, actually reply to use owners of doo's. I would be willing to list my s-n so they could check that it is still under warranty.
ok
 

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After rereading this, I agree with WOT.
So, I guess it is really a fuel mapping issue. Sled goes lean, program calls for more fuel, temp probe shows over temp, program calls for more fuel. Round and round she goes, till something blows..
 

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one fast 98 mach-z
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Discussion Starter · #13 ·
After rereading this, I agree with WOT.
So, I guess it is really a fuel mapping issue. Sled goes lean, program calls for more fuel, temp probe shows over temp, program calls for more fuel. Round and round she goes, till something blows..
Not a good thing a hundred miles from the nearest road.
 

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Edlund .I think I posted before on someones thread before.
Its a fuel mapping program.
But it also is part Tps sensor and EGT sensor. if these 2 sensors are not in the correct range at idle it will change or for your situation be a rich fuel problem.
For everyones info the sensor in the exhaust is a temp sensor.
You need to find a good dealer or dealer tech that knows the latest remap code and can verify it is downloaded into your sled.

And now that ambient temps are way above normal operating temps in the winter .I wouldn't expect too many good techs to try and get your sled tuned right now.

but it is a fuel maping problem.
We had 2 sdi's that run with us ,that had the same problem as you. all were fixed by remap from buds from dealers.
Rich
 

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After the first time I saw it, I knew it was because I had been in the midrange for a long time. That was that last time it happened.
I took mine to dealer, and we found no faults on buds. I had expected to see an over temp on the exhaust probe.
For the most part my sled has run pretty sweet. Only 3100 miles. Other than the lean issue, no other problems. I have been a happy camper. In hope the electronics hold on for many more years.
 

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one fast 98 mach-z
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Discussion Starter · #16 ·
edlund said:
Does anyone think a rich fuel mixture with a 600 sdi could cause a red glowing exhuast can at night? And if so why? 90% of the people say it is caused by a lean fuel to air mixture. But I am willing to listen to other reasons. thanks

[snapback]726800[/snapback]​
This is what my dealer told me. At about 7000 rpm the engine runs very lean, the exhaust gas probe senses this and trys to lower the temps by adding more fuel. If you do not move the throttle any, the sled then runs way to rich, the fuel that isn't getting burnt in the engine burns in the can causing it to get too hot. So yes, it is actually a rich fuel mixture.
?
 

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one fast 98 mach-z
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Discussion Starter · #17 ·
After the first time I saw it, I knew it was because I had been in the midrange for a long time. That was that last time it happened.
I took mine to dealer, and we found no faults on buds. I had expected to see an over temp on the exhaust probe.
For the most part my sled has run pretty sweet. Only 3100 miles. Other than the lean issue, no other problems. I have been a happy camper. In hope the electronics hold on for many more years.
ok
 

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one fast 98 mach-z
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Discussion Starter · #20 ·
Does anyone think a rich fuel mixture with a 600 sdi could cause a red glowing exhuast can at night? And if so why? 90% of the people say it is caused by a lean fuel to air mixture. But I am willing to listen to other reasons. thanks
 
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