Catalytic converter in a 1989 mitsi galant ?

mystyk, May 21, 8:22am
Does anyone know anything about the catalytic converter and if it can be changed for an ordinary muffler instead.I think this is what's causing my car to overheat when driving long distances.

andy61, May 21, 8:49am
It would be more likely a cracked head.Very common on Mitsubishis

mystyk, May 21, 8:56am
I thought about that first but I can drive it around town for weeks and it doesn't overheat or use water. It's only when I'm on long drives and more so if it's going uphill.It's really gutless going up hill too.it hardly uses any oil either.

safteystv, May 21, 9:03am
simple test of blocked exhaust, at idle hold hand close to muffler , get griend to rev car feel if exhaust pressure increases , not much of an increase meens restricted flow , good to high pressure . not blocked , does happen only seen it twice . on diesel and petrol .

phillip.weston, May 21, 9:05am
what engine! is it using coolant! The cat converter light should be coming on if it's blocked or the cat converter itself is over-heating.

mystyk, May 21, 9:09am
It's the 4g37 engine which is an 1800 sohc. It's a jap import. I've had coolant in it. Water seems to be getting forced out through the overflow. Have flushed radiator, replaced cap and checked thermostat.

neville48, May 21, 9:11am
Give it a birthday and a tune-up, get the radiator stripped and rodded and flushed and get rid of the cat, they are a waste of space,just get it removed and a bit of pipe put in where it was.

mystyk, May 21, 9:24am
Yea I was wondering if I could just take it out. So is a bit of pipe enough to replace it with. You don't need to put a muffler in it's place!

neville48, May 21, 9:55am
yep, you should have a muffler and resonater on the pipe also.

mystyk, May 21, 10:14am
Yea there is. Sweet thanks.

phillip.weston, May 21, 11:33am
ahh the old 4G37 - hate to tell you but I be leaning towards a blown head gasket. The 4G3x saturn engines are prone to blowing head gaskets and the 4G37 more so due to having the largest bore size for that family of engines and therefore not much meat between cylinder walls. Good news is those engines don't tend to crack heads, that's more a 4G62/4G63 SOHC thing to do.

I would do a compression and a tee-kay test to confirm if combustion chamber gasses are escaping into the cooling system or not.

mystyk, May 21, 1:35pm
Ok will do that before I do anything else. Just doesn't seem to be losing water often enough for it to be the head gasket but it's possible so will check.

guest, Jul 18, 11:23pm
Its definately the catalytic converter. It has a sensor on it. Will this cause any problems when I remove it along with the converter?