Low Fuel Economy; Low Power

[RobK]

Hi all! I've looked over this site for weeks now and I know you all are the ones to talk to. So......I recently purchased an R Title 03 Vibe Base w/moon and tunes. (I already know that I'm dumb for buying an R Title. But I digress..)Mileage was at 154000. Test drove that thing for 30 miles, and was perfect: just like a new car. Seller told me it hit a deer and was bought out by insurance (BS talk that all dealers do)I bought for 3000. Two days later heat went out. Next day temps went up. Took to local mechanic and started cheap: replaced thermostat, then water pump, then radiator(with flush of course). Nothing changed. Then discovered it was a warped head. Had that fixed, but then a coil pack went bad. Replaced that, and did a tune up. Everything was fine for two weeks...then engine light came on again. I started to have poor fuel economy and noticed the car wasn't as powerful as when I had it fixed. Took to Autozone and code readout said "Catalyst efficiency low" or something; maybe the dreaded 420 code? But after seeing that the cat may be at fault now, I decided to check on symptoms of bad cats. Out of several symptoms, only one matched, which was the poor power and fuel. But I was wondering if it could be a vaccum or a sensor that would be cheaper to fix myself. I've already paid total 4500 for the car now, and the car still runs, although a little loud and not as good, but I would love to hear that I can fix this myself. Is there anyone out there that has this problem? Should I trade this in toward something else? I love this car and know that for the mileage and past problems this car has had I feel that this car can go to 300000 if I just figure out this current issue. Help me!!!!!

[RobK]

Also, if anyone has a picture diagram of the location of the catalytic converter, as well as a picture of all vaccum hoses that could effect the car's performance, please send me. Thanks again.

[Baltovibe]

Sounds like a possible clogged catalytic converter. Any restriction will lower engine performance and increase gas usage.

[RobK]

OK, quick update:Yesterday I checked the oil level and it was a half quart low, so after putting it in I noticed the Engine Oil Light was off, power was back to normal, hell even the gas consumption slowed down to new car standards...I thought "Oh hell yes!!!"....until I noticed smoke coming from the hood. I pulled over and pulled up the hood, and saw oil everywhere. Turns out I didn't put the oil cap back on the engine. No real problems other than cleaning off the oil at the car wash, but the engine light stayed off and the car ran like it was new. Now this morning, I just noticed the engine light back on, other symptoms yet to surface. I say all this to ask, Why would the car act normal when the oil cap was off? Does this reinforce the catalytic converter as the main suspect or does this point to another problem?

[Entelodont]

Could the Exhaust Gas Recirculation valve be stuck or clogged somehow? If the oil cap is off, the engine would vent the fumes instead of recirculating them. Just a guess, though.

[northvibe]

with that many miles and that age, I'd have an exhaust shop check your cats. If you have a clogged or bad cat, it will show those exact symptoms. Then the cheapest fix is to just remove the cat. But that could depend if your state has emissions testing. although most cars have 2 cats.

[RobK]

if it was the Exhaust Gas Recirculation Valve, is it something that I could replace fairly easy? If it's not obvious enough, I don't have a lot of money to take to the shops anymore (I already spent close to 2 grand in repairs already). I don't mind spending another 100-200 bucks on a needed part if I can install myself...but in that event I would need a step by step instruction on how to replace it. It's a shame really. I love this car, looks great, runs nice except for this problem. Feel like a real sucker.

[RobK]

ok, now for an update:I just bit the bullet a week back and replaced the cat (or should I say double cat???) with an OEM part. Car runs great. However,another engine light came on. Two codes popped up, one indicating the O2 sensor, the other the coolant temp sensor. I just took out both O2 sensors and cleaned them along with the sensor alongside the air filter and put them back in. Went to Autozone and the O2 sensor code disappeared but the coolant temp sensor remained. How serious is this? Can I do without this part for awhile? The car runs new again, but the gas efficiency still isn't where I want it to be yet..maybe 20 mpg?

[joatmon]

I could see where the computer would modify the air/fuel mix for cold engine conditions, and that mix would be inefficient, designed to get the engine up to efficient operating temperatures. It might even be possible that long use with such an inappropriate mix might affect the cat, but that's just a guess