IS A TUNE NEEDED FOR CATTED DOWNPIPES
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Joined: Jan 2018
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S205 C63S
IS A TUNE NEEDED FOR CATTED DOWNPIPES
I thought I'd start a thread for a definitive answer on whether or not an ECU tune is required for downpipes with cats in them.
This is for all reasons apart from a check engine light. I'm talking about engine safety, drivability etc etc.
Im lead to believe that a 300 cel cat 'should not' throw a check light but still could. 200 cel and 100 cel have more chance of a check light.
Is a piggy back beneficial if you have catted downpipes?
Experts please chime in with corresponding answers.
This is for all reasons apart from a check engine light. I'm talking about engine safety, drivability etc etc.
Im lead to believe that a 300 cel cat 'should not' throw a check light but still could. 200 cel and 100 cel have more chance of a check light.
Is a piggy back beneficial if you have catted downpipes?
Experts please chime in with corresponding answers.
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From: Houston
2003 W211 E55, 2003 W220 S600
Well with catted downpipes you will not trigger a CEL corresponding to a O2 sensor, but on a stock ECU you may trigger a boost pressure exceeded code due to less of a restriction in the exhaust which causes the turbo to spool up faster. This will put the car in limp mode and cycling the ignition will reset it, but you will still need to cleat the CEL via a OBD2 scanner.
