Cracked down pipe flex pipe.
#1
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I was searching hear in forums to see if anyone else had this problem and found the answer.. to just replace the the flexpipe in any muffler shop. I took the down pipe out and there it was a crack in the edge of the flex.. took it to a few muffler shops including mieneke and was told the flex part can not be replaced... Can anyone tell where they got there'* done?
Also getting a p0301 code cylinder #1 misfire detected.. is my cracked flex pipe the cause?
Thanks.
Also getting a p0301 code cylinder #1 misfire detected.. is my cracked flex pipe the cause?
Thanks.
#2
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The flex pipe can be replaced. I just had a new one installed on my system. Check ZZPerformance and 3800Performance..they carry down pipes and flex pipes.
The misfire you are showing should not be related to the cracked flex pipe. Check your coil and wires https://www.gmforum.com/t278818/
The misfire you are showing should not be related to the cracked flex pipe. Check your coil and wires https://www.gmforum.com/t278818/
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Yes, you can change the flex pipe, go to a custom exhaust shop, not a big box place. The misfire could be from the exhaust leak. The leak makes the PCM think it'* leaner then it is and can cause problems by making it rich. Fix the cracked pipe before you change anything else.
#4
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Thanks guys,
I searched in these sites already and cannot find the original flex part on it'* own..What they have is the after market down pipe with a braided flex on it. Witch claims it can add 10 to 11 hp, sounds good to me ..How true is this? Hogan performance has it DP8S shipped 3 TO 5 business days.
What I was trying to avoid was parking the car for a week. Kevin did the muffler shop have this piece or did you have to order it? I was reading here the shop could replace it for about 70 dollars parts and labor.
Now as far as the trouble p0301 code, it is a coincidence that it happened wright after the flex down pipe started making noise.
I searched in these sites already and cannot find the original flex part on it'* own..What they have is the after market down pipe with a braided flex on it. Witch claims it can add 10 to 11 hp, sounds good to me ..How true is this? Hogan performance has it DP8S shipped 3 TO 5 business days.
What I was trying to avoid was parking the car for a week. Kevin did the muffler shop have this piece or did you have to order it? I was reading here the shop could replace it for about 70 dollars parts and labor.
Now as far as the trouble p0301 code, it is a coincidence that it happened wright after the flex down pipe started making noise.
#6
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What they have is the after market down pipe with a braided flex on it. Witch claims it can add 10 to 11 hp, sounds good to me ..How true is this? Kevin did the muffler shop have this piece or did you have to order it? I was reading here the shop could replace it for about 70 dollars parts and labor.
An aftermarket down pipe and flex will not gain you that much HP. Now if you added in a hi-flo cat and low restriction mufflers and some headers, then you will be seeing the 10+ hp gain.
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Thanks again guys,
I will most likely order from Hogan Performance DP8S..I do have a Hi-Flow cat in the Bonneville already lets see if later the the line i'll do the other mods.
Hogan'* Performance qoute:
This downpipe was developed to increase exhaust flow in the most restrictive area of the exhaust on the 97-03 Bonneville with a 3.8 SC and 3800 NA engine.
This pipe was installed on one of our clients cars recently. Dyno pulls were performed before and after the install with a 10-11 H.P. increase. The Dyno Sheet shows 2 pulls blue and red before and 2 pulls green and purple after.
Key Benefits
409 Stainless Steel mandrel bent tubing
Stainless steel flex coupler
Custom Cut 3/8 inch thick steel flanges
True bolt on with simple hand tools
I will most likely order from Hogan Performance DP8S..I do have a Hi-Flow cat in the Bonneville already lets see if later the the line i'll do the other mods.
Hogan'* Performance qoute:
This downpipe was developed to increase exhaust flow in the most restrictive area of the exhaust on the 97-03 Bonneville with a 3.8 SC and 3800 NA engine.
This pipe was installed on one of our clients cars recently. Dyno pulls were performed before and after the install with a 10-11 H.P. increase. The Dyno Sheet shows 2 pulls blue and red before and 2 pulls green and purple after.
Key Benefits
409 Stainless Steel mandrel bent tubing
Stainless steel flex coupler
Custom Cut 3/8 inch thick steel flanges
True bolt on with simple hand tools
Last edited by XEN; 04-25-2009 at 09:22 PM.
#9
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Just a bit of caution when reading a manufacturers advertisement about HP gains and dyno results....don't believe everything you read! Most of the dyno results that I tend to believe are those submitted by members, and race engineering/development companies.
Like Dan said, you will have a greatly increased exhaust flow and your 'butt dyno' will more than likely feel the difference. Seeing that you already have a hi-flo cat, you will probably notice it even more.
None the less....you will like it!
Like Dan said, you will have a greatly increased exhaust flow and your 'butt dyno' will more than likely feel the difference. Seeing that you already have a hi-flo cat, you will probably notice it even more.
None the less....you will like it!
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#10
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Hogan developed and tested that downpipe on TommyGloves car. I later bought it from him. Hogan'* qualtiy is good and I was happy with the way it performed before going to headers.
A crack in the exhaust could be causing a slightly issue, however since the flex is well after the O2 sensor in the rear manifold, I don't see how it would cause only a cylinder 1 misfire. While waiting for the downpipe to be fixed, I'd check the plug, wire and coil. All free to look at and check.
A crack in the exhaust could be causing a slightly issue, however since the flex is well after the O2 sensor in the rear manifold, I don't see how it would cause only a cylinder 1 misfire. While waiting for the downpipe to be fixed, I'd check the plug, wire and coil. All free to look at and check.