catalytic converter question - PeachParts Mercedes-Benz Forum

jasonkec01 · #1 10-12-2007, 10:01 AM

i've searched around but am unsure if my theory is correct.my cat is probably original,after 200k and 22 years.my question involves performance and the 02 sensor. i'm thinking now my 02 sensor could've overheated because of a crapped out catylitic converter.the day/2 before i began having all sort of performance issues, i put in a bottle of LUCAS INJECTOR CLEANER on a full tank of B.P.[amoco] high octane. i always use premium gas and less than 5,ooo miles ago had the injectors replaced. i've removed the # 1 plug and it looks great. my oil smells gassy though and i honestly can't say if i remember oil ever smelling gassy before....... so, heres my theory... my cat is bad,i clean the injectors and that frees up a bunch of gunk sent to the cat which is already shot or very close too. that clogs up the cat much worse, overstresses/heats the 02 sensor/burns it out.........i end up with crappy performance.............am i going somewhere besides the wrong direction ??? i've got enough into this car already to have put my kid through college...not too excited to do much more than i have too. !

jhodg5ck · #2 10-12-2007, 10:08 AM

You can replace that stock cat w/ a high flow for a few hundred $ installed.. It will release some HP/TQ and still keep you burning clean.

O2's really want to get changed after 40K as their response time slows which also makes life harder for the cat.

I'd be surprised if what came loose after running FI cleaner would make life That much harder on your cat...if anything the improved combustion would then make it's life easier!

Jonathan

jasonkec01 · #3 10-12-2007, 10:11 AM

my theory again lies in the age of the cat,yet also because of my 02 sensor smoking so bad[white smoke] it filled my garage up in 3 minutes after about a 150 mile trip.all of this happened consequently after i put in the lucas. i guess i could've mentioned the 02 sensor smoking too. sorry,i'm stumped ! also, before i got the car the 02 was bad for probably 75k before i replaced it under 5k ago. could that compound the bad cat before i got it? or does the 2 even effect the other ?

brewtoo · #4 10-12-2007, 12:26 PM

O2 sensor smoking?

The O2 sensor is aead of the cat, isn't it? So how could the cat affect the O2 sensor at all?

jasonkec01 · #5 10-12-2007, 03:32 PM

hey,,,i got no clue bout' nothin' really. you are correct though sir....the 02 is approx. 2-3 in. away from the cat. my reasoning for that line of thought goes back to the mysterious white smoke[at 02 sensor],combined with some SERIOUS reduction in performance. ovp is good,battery,coil,plugs,cap,rotor,voltage regulator,ICV ,air mass,fuel distributor, all brand new[w/in 5k miles].trans. brand new,fuel relay is new,injectors new,a/c compressor new......several other things. as stated before, #1 plug looks great.gas tank releases lots of suction as it should when i remove cap. oil pressure is great,all fluids w/in 3k miles of last change....................???????????????? Since i first began writing any of my questions, i ended up finding out i have a super loose connection at my ICV. i tried removing it to see a change.when i pulled on it it slipped off like it was greased it was so easy. i figure immediately that couldnt be right. i reseated it and immediately the slight surge in idle went away and the engine seemed to smooth out overall.i've only testdriven abou 1.5 miles at a top speed of 60, so i really dont know the overall performance just yet,but im thinking that helped a great deal.