Go back to previous topic
Forum namePerformance/Engine
Topic subjectafter testpipe
Topic URLhttps://forums.2gnt.com/dcboard.php?az=show_topic&forum=i5&topic_id=41551
41551, after testpipe
Posted by Gregstootall, Jan-13-03 12:54 AM
after i put a 2 1/4 inch test pipe on my ride it smokes..as soon as it was put on and started was when i noticed the smoke....what can i do to fix this? i dont want to get a high flow cat because i love the sound and performance
41552, RE: after testpipe
Posted by Justin99RS, Jan-13-03 12:59 AM
since you put in a testpipe--you got ride of the cat...which filters out the smoke, without at filter, all the nasty stuff that didn't get out before, now gets out....
41553, RE: after testpipe
Posted by Gregstootall, Jan-13-03 01:04 AM
so juss dont worry bout it or what?? cas it looks nasty when me and my girl go ridin or to a meet to street race....
41554, RE: after testpipe
Posted by coppereclipse95, Jan-13-03 01:58 AM
Are you sure its not just the weather??? I took my Cat. Conv. off about a year now, but mine never smoked that bad. It does now because of the weather in the morning. But once it gets going...you can hardly see anthing...
41555, RE: after testpipe
Posted by Gregstootall, Jan-13-03 05:11 AM
ok after I had the cat cut off the plugs are black I've pulled them 3 days in a row and cleaned them and they keep gettin black again,what's causin diz,it didn't happen untill the cat was cut off
41556, RE: after testpipe
Posted by vegasdsmr, Jan-13-03 05:36 AM
your plugs are getting black because after pullin the cat, your downstream o2 sensor is reading diffferent mixtures of air and fuel, and the ecu drops a lot more fuel to be "safe" when your o2 sensors fail.

black ressidue on your plugs means your runnin rich, which hinders performance, yet keeps your engine from blowin up...

the smoke is somewhat normal, but i would reset your ecu, or disconnect your neg cable on your battery for a good 10-20 minutes, and see what your plugs look like 5 days after....

good luck
41557, RE: after testpipe
Posted by Gregstootall, Jan-13-03 06:02 AM
ok .... i'll try it and let u know how it goes...
41558, RE: after testpipe
Posted by WickedESi, Jan-13-03 09:35 AM
>your plugs are getting black because after pullin the cat,
>your downstream o2 sensor is reading diffferent mixtures of
>air and fuel, and the ecu drops a lot more fuel to be "safe"
>when your o2 sensors fail.

This is not correct. The downstream o2 sensor does not effect the mixture AT ALL. All it does is trigger the CEL when it senses unburnt fuel passing the cat., for emissions purposes.
41559, RE: after testpipe
Posted by OZ_GS, Jan-13-03 11:18 PM
Thats ^^^^^ what I thought aswell....

I thought that the rear O2 sensor did not affect the fuel curve at all. I was under the understanding that it was just there to tell you if your CAT was bad (or missing) hehe

I had my CEL on from a gutted cat for several months and did not notice my car running any more rich than before ie, no extra smoke out the back, loss in performance, nor worse gas mileage. I did finally fix the CEL this past weekend with the little resistor.

Chad
41560, RE: after testpipe
Posted by Gregstootall, Jan-14-03 03:58 AM
i got alot better performance and bad gas millage better sound cel was on until i unhooked the battery to restart the computer then it went off.....havnt checked the pluges yet ...i'll let u know how everything turnsout
41561, RE: after testpipe
Posted by MotoFool, Jan-14-03 05:43 AM
oz_gs what resistor did u use or did u use a casper electronics o2 simulator?