Catalytic converters, anyone ??

MootsMan · Post by **MootsMan** » Wed Jun 08, 2005 10:28 pm

I have an '85 SR5 that has just turned 150K miles. It's been running really great lately, no problems at all. Fuel mileage has been anywhere between 27.5 and 30, with most of my driving being freeway, but I usually drive 70mph.

Anyway, this afternoon I drive into Nashville ( 35miles ) with no problems. I make a stop or two, and the car cranks up and goes without any problems then, too. But when I get in the car to come back home, I notice that it seems there is no power. I thought maybe the emergency brake was stuck, since my instrument panel brake light has been coming on ( separate issue, will address that in another post ). However, going downhill on a slight grade to the freeway, I could tell that it was rolling without any resistence from the brake. I get out on I-40, and the car has no power at all. I can't even use 5th gear, and I have the accelerator floored and only getting up to about 55 on a downhill, slows to about 30 going uphill. My wagon normally idles at 1100-1200 RPM's, but tonight it's been 500-700. It does idle, and it idles smooth, but there is no power when you push the accelerator down.

The converter is my guess, as I've experienced other cars with the converter plugged or whatever it is that they do, and the symptoms are the same. Any other ideas from any of you ?? I'd appreciate your input...I have to get this thing going again SOON ! Is the muffler shop my best bet for repair ?? or is this something that NAPA or AutoZone will have the part and I can replace it myself ??

Thanks for any help you can give me, guys !!

clbolt · Post by **clbolt** » Wed Jun 08, 2005 10:35 pm

Normally if a converter goes that quickly, you'll be able to tell the difference in the sound of the exhaust. I'd check to see if the timing belt slipped a tooth or 2.

jetswim · Post by **jetswim** » Thu Jun 09, 2005 5:16 am

What about a fuel pump not delivering enough PSI?

GTSSportCoupe · Post by **GTSSportCoupe** » Thu Jun 09, 2005 7:28 am

I've had the same experience with a catalytic converter before too. Have someone rev the car up while you put you hand over the muffler output. If you don't feel much exhaust flow, your cat has probably had it. The bolts holding in the cat are usually rusty as hell, you will probably have to grind them off. If you are looking for a quick solution, remove the cat, punch the stuff out with a hammer and a rod, then put it back on with new bolts and lock washers. Then, get a new cat later on if you need one or are concerned about the environment.

dug320 · Post by **dug320** » Mon Jun 13, 2005 1:42 am

Before you start ripping apart the exhaust. Fill your gas tank from another station. Your symptons sound more like bad gas. You may to change the fuel filter.

Either way it won't hurt the pocket book.

MootsMan · Post by **MootsMan** » Sat Jun 18, 2005 1:05 pm

Thanks for all the suggestions, guys. I had a guy take the converter off today and put a pipe in. He got several wads of material out of the pipe, stuff that had come out of the converter. It's still idling low, however. He suggested I replace the plugs, as the ones in the engine were probably fouled, and also said the stuff blocking the pipe could have created enough back pressure to cause the timing belt to jump a notch or two. I'm having my doubts about the plugs, simply because the idle is still so low ( 500-600RPM as opposed to 1200RPM before ) The car has a little more power out on the road now, but it's still will not get up a hill with any speed at all......it's like the car has a govenor on it that keeps it capped at 65MPH on the downhills and flats, and then you keep your fingers crossed hoping you'll get up any incline before something runs over you.

As I've said before here, I'm not much of a mechanic....doing a lot of this stuff is entirely new to me. Is adjusting the timing something I can easily figure out from the FSM ?? or should I leave that to an experienced mechanic ?? Also, if it is an issue where the timing belt has slipped, is there a chance that the belt strength may have been comprimised, and that it should be replaced ??

Thanks ahead for any more suggestions , folks !

MJ

clbolt · Post by **clbolt** » Sat Jun 18, 2005 1:07 pm

If the belt has jumped, then yes, you should replace it. As cheap as a Tercel timing belt is, there's no excuse not to.

MootsMan · Post by **MootsMan** » Sat Jun 18, 2005 3:26 pm

Well, I just did the test drive after installing new spark plugs.....still no power up the hill like it used to be.....idling is still at about 700 RPM.

I checked the oil, because this all happened in a day or two after an oil change....and there was a bit too much oil in the car. Could that be my problem ?? I drained the excess....mabye a pint.....any problems that would cause with the power of the engine ?? I'm just trying to figure out what happened.

I consulted the FSM on oil level....it says 3.5 US Qts. I know I didnt' put any more than that in it, but possibly I didnt' get it completely drained.

Mac · Post by **Mac** » Fri Jun 24, 2005 12:25 am

a clogged cat will cause overheating, and your exahust manifold will probably glow red hot.

Typrus · Post by **Typrus** » Fri Jun 24, 2005 12:56 am

Hmmmmmmmmm.........

For stuck bolts, use PBBlaster. Available from auto supply stores. For REALLY stuck bolts, heat them up with a torch or the likes then spray PBBlaster on it untill it stops steaming. Use bursts, not a constant spray.
*Note. With this, use common sense. Don't put a torch to a bolt that goes through rubber or plastic unless you have full intent on replacing the now molten part.

Do you have an oily residue behind the fuel pump on the firewall? Do you smell strong gas in the oil? Do you smell gas when you hit the accel. hard? You might have a fried fuel pump. Not hard to replace, and not too expensive.

Alright. Moots. Go to NAPA or Autozone. Buy 2 cans of Sea Foam. That'll run you about $15. Also but 1 can of Deep Creep or a high-quality Carb Cleaner (I used B-12 Chemtool). That's a little bit more. Buy a new fuel filter. Maybe $4 there.
Go to a fueling station. Pour in 1 can of Sea-Foam (in the tank). Fill up on Midgrade.
When you're at home, while idling, give the throttle some juice (you can access it at the back of the carb) and spray bursts of cleaner around the walls and center of the barrels, while revving occasionally. Stop the engine and spray a good bit down either barrel. Let it sit for a bit (20 mins or so) then go drive for maybe 5 mins. Then, stop the engine. Get access to the carb again. See those two tubes coming out over either barrel? One pointing up, one pointing in and down? Put your finger over one and spray down the other with the cleaner for a few secs. You might get a little splashback. Thats not an issue. Switch tubes. Spray. Switch again. Make sure you do each tube twice. Let it sit for at least an hour. After an hour, drive it hard for 5-10 minutes.
During the cleaning process, you may get some grey or black smoke that smells HORRIBLE. Thats a sign that you are burning out lots of crap. Thats a good sign.

After you have gone through one tank, refill with Midgrade or Premium and run the other can of Sea-Foam through. After this tank, replace the fuel filter.

By the way.... Hows your air filter look?

MootsMan · Post by **MootsMan** » Fri Jul 01, 2005 10:20 pm

I finally took my Terc to a mechanic who was able to diagnose and fix the problem. After removing the catalytic converter and replacing the spark plugs, it was still running almost as bad as before . He determined that it was the vacuum advance, and that the timing had been set too high. Anyway, he worked on the centrifigal advance and replace the vacuum advance, and it seems back to normal now. The idle is set at around 800-900, instead of 1200. It seems to run fine and has good power out on the road.

The vacuum advance was $139 from NAPA....not cheap at all.

Thanks for all the suggestions. I think I'm gonna try your process pretty soon, Typrus. I'm sure this engine has a lot of gunk in it that could be cleaned out !