Catalatic converter

[Racerx250 10+ year member]

Can you hear anything rattle under the car idle/ or accelerating?

If so there is probably junk in your cat. You can possibly try to seafoam it.

A misfire on cyl 3 won't affect it to were you would notice at idle. If you put it in drive and push the brake almost to were you'd powerbrake if WILL misfire it there's a problem with your coils. As far as your cat goes have the shop check it out. They will know but don't let them screw you around. Take it to two or three shops to get several opinions,

 

[IgnoreMe 5,000+ posts]

but i havent noticed a misfire?? Engine wise it seems to run fine @ idle.. Doesnt a misfiring cyclinder affect your idle?

a constant misfire can damage your catalytic converter...

you should probably clean up that misfire before you tackle replacing the converter.

 

[bad @SS chevy 10+ year member]

whats causing my shit to misfire though??? I think the misfire code came up right after i did my plugs.

 

[IgnoreMe 5,000+ posts]

whats causing my shit to misfire though??? I think the misfire code came up right after i did my plugs.

did you gap them correctly?

 

[bad @SS chevy 10+ year member]

Yes, pre gapped plugs...

 

[bad @SS chevy 10+ year member]

I dont think the misfire code is anything major, i think i just need to clear the codes.. Still wouldnt cause my shifting to be jacked up though right?

 

[IgnoreMe 5,000+ posts]

Yes, pre gapped plugs...

i dont trust "pre-gapped" plugs. id recheck everything you did if it were me.

secondly, if you just started having a misfire i wouldnt blame it on taking the cat out. but certainly dont put a new cat in unless you can fix the misfire first.

 

[IgnoreMe 5,000+ posts]

If im on the gas, full throttle its fine. Shifts great. The problem im facing is at medium acceleration. Im getting a shutter/bog/bouncing idle. Sometimes it feels like it doesnt want to shift. its really bad @ the 45-50 gear shift.

its only at that speed? ****** shifting is going to be controlled by the valve body (if you've ever seen a valve body its got valves to direct pressure which will shift gears) so if you have shifting issues that are always present in the same upshifts it could point in that direction.

how many miles are on the car (assuming these are all original parts?)?

edit: haha, what the **** was i talking about? balls and shit?

 

[bad @SS chevy 10+ year member]

110,000 miles

and yes, the bad shifts are at the same speeds, everytime...

 

[Racerx250 10+ year member]

err.. You said you just changed your ****** fluid and filter... How many miles ago did you that before now?

 

[IgnoreMe 5,000+ posts]

110,000 miles
and yes, the bad shifts are at the same speeds, everytime...

do you feel the engine bogging down at the same time you get a bad upshift? or slightly before? or is it just always bogged down?

 

[IgnoreMe 5,000+ posts]

err.. You said you just changed your ****** fluid and filter... How many miles ago did you that before now?

lets hope that fluid was still brown when he took it out and not black lol

 

[bad @SS chevy 10+ year member]

Engine bogs/ idle jump @ the same time as it badly upshifts..

trann fluid changed 5k miles ago

 

[budahbuddy803 10+ year member]

i think the same thing has happened to my car, except i am not spending any money to fix it, if it dies it dies. I first noticed rattling in the cat and then it stopped and i have terrible idle and shifting problems. It might be my ******, but i am pretty sure it has a lot to do with a horrible rusted cat.

 

[IgnoreMe 5,000+ posts]

Engine bogs/ idle jump @ the same time as it badly upshifts..
trann fluid changed 5k miles ago

what exactly do you mean by "idle bouncing" and "idle jump" ? do the rpm's rise at that same particular upshift?