some advice for an amature. catalytic converter

[dewloft]

So I thought this was going to be a super quick fix after reading my service manual which explained 4 bolts and that's it. But when I jacked it up and wrenched on I broke two of the heads. Is there a secret to getting them out. Can I punch them through or is the connection threaded also? Its a bit hard for space with my small jack. I hope this didn't turn into nightmare seeing as I just sold it to a friend.
I am thinking that if I can punch them out it should be no big deal. But if not... Not sure what to do without having to start cutting stuff?

[dewloft]

Oh yeah it's an 84 DLX if that helps at all

[Petros]

the bolts usually rust. soaking them overnight with ATF (yes, transmission fluid) usually works to loosen them, but if badly rusted it might take a cutting torch.

What was your "quick fix"? might be easiest to take it to muffler shop and have them cut it off and install the new one (if that is what your plan was). Or you might cut it off yourself with reciprocating saw with a metal cutting blade in it, and than take it to a muffler shop shop to install the new one. Or just replace the bolts.

[c_j]

My catalytic converter is bolted on with 12MM bolts (17MM head). Nuts on the back, so neither of the flanges are threaded. Someone else might be able to say if that is how they all are, or if some have threaded flanges.

You can see a new catalytic converter bolted on here:
https://tercel4wd.com/forums/viewtopic.php?f=4& ... ker#p69305

[dewloft]

The quick fix is pulling out the old cat and throwing in a new one. I have done everything I know to try and stop the rough idle/wanting to die at stop lights problem. Fuel filter, plugs and wires, O2 sensor, air filter. I finally just got the oil light off by replacing the oil preasure sensor, which was leaking as well and could have been a bad situation. My issue is that it runs great when athigher speeds, nice and strong. But when I am at a stop light it wants to die and sounds as though is struggling for air.
It idles fine when I first start it letting it warm up. But as soon as I get to that first light it acts as though it wants to poop out on me. It is a bit power less at low speeds and sometimes stutters when first taking off. It runs really well above 10 miles per hour. If you have any imput and can weigh in on it being the cat it would be appreciated.
Oh and the new cat I purchased isn't direct fit, but when I purchased it at O'reily the guy said it required no welding or cutting for installation? Is that possible if it is straight pipe on either end with no flange? Thank you guys, and thanks for the exhaust diagram.

[dlb]

dewloft, my guess is your crappy idle is due to a carb issue. incorrect vacuum hose routing, broken vacuum diaphragms, poor carb tuning.

i would go over all the hose routing very carefully. if you can't tell which hose goes where, disconnect both ends of what is supposed to be the same hose, blow through one end, and make sure air comes out the other side.

for vac diaphragms, pull the hoses that go to each of them and suck. if you can suck air through them, they're broken. plug the hose that goes to that diaphragm until you can replace it.

tuning the carb can take a bit of fiddling but there is only 3 screws so it's not too bad: idle, fast idle, and idle mixture. set them using the steps in the FSM.

also check the AAP using the FSM test.

one last thought, test the fuel cut solenoids. i have found when they malfunction, they can cause some really rough idles.

i know that sounds like a lot to go through but it's really not too bad. good luck.

[Petros]

sounds like a vac leak to me, a bundled up cat would loose power at high speed and run normal at idle and low rpm.

as DLB suggested, check your vac hoses, and the routing. check the vac operated parts for leaks, check the intake manifold for leaks at the gasket.

[dewloft]

Okay thanks guys. It has a real smokey start but then goes away after a couple minutes, is there anyway that info could help lead me to the clogged hose/leaky vacuum?

[Petros]

"smokey"? You mean you get a lot smoke out the exhaust right at start up? If it is bluish smoke it is like leaky valve stem seals, not a big deal and it should not affect the way it runs. As an engine ages these get brittle and do not seal as well, normal for older engines, as long as the spark plugs do not get fouled they can run for a long time without any issues as long as you keep the oil topped up.

If it is whitish smoke (steam that dissipates fast, unlike the bluish smoke), that it could be a bad head gasket, which will often affect cold starts with stumbles. Are you loosing coolant? where you have to top it up once or twice a week? If so that points to a leaky head gasket.

[dewloft]

Okay thank you guys. I ended up taking it to a mechanic cause the carburator was out of my league. The vaccums checked out, and he did work on the carb making it run much richer and taking the studder out of it. The smoke is blue, which is. good news. A leaky valve stem. I will have to research and see if it is in my scope of skill. I just sold the car to a friend, thank all of you for you time and help during the time in which I owned this awesome little car.