need help!!!! CAT problem!!!
alright ive been chasing this problem for about 6-8 months. my check engine light code says "catalytic converter efficiency low" so. I replaced the CAT.... still having problems... some days it will run fine, others it will run like its about to die, IF it runs at all!!!!! it back fires every so often, has major horse power loss, like I can barely go over 30 mph sometimes, and once I do get u to about 25 or 30 it wont shift into the next gear, it just revs up but doesn't shift or gain speed. it is eating up gas more than ever, maybe getting 6-8 mpg. I know the ignition coil is out which is causing it to have problems starting, but that's getting fixed soon. im starting to think the cat I put on it is too small? I went cheap and baught it off a website, and when I replaced it, I noticed the one I put on there is maybe a half to three quarters the size of the bad one I took off... could this be the problem? it said the cat was for my make model n year of jeep, but I dunno if it being so much smaller could be making these problems continue.... should I just fork out the 200 bucks to buy another CA or what? any suggestions would be greatly appreciated!!!! I am legally disabled and require my car to see my doctor and hospitals etc... so having my jeep run like crap, if it runs at all, is ruining my life! thank you to anyone who can give me suggestions or things to check. (btw ive also replaced both of the 02 sensors and the crankshaft position