'98 camry bucking/surging

[sigh]

Hi,

Sorry for the long winded post but I wanted to put out as much info as I could.

Over the past couple of months my 4 cyl camry has been progressively getting worse and I need some advice. The problem started with a mild bucking at steady highway speeds, and is getting worse. It also has a bad exhaust smell (kind of gassy/smokey), I can't drive with the windows down because it fills the car. Accelerating and decelerating are OK but it doesn't seem to have the power it used to. Then it started surging up and down a couple hundred rpm's during light acceleration around 2K rpm. Now the surging is getting worse. I had similar bucking problems on other cars so I did what I did to those to fix them. Replaced air filter, spark plugs and plug wires. After the surging started I was guessing fuel, so I bought a Scantool for my laptop. The MIL code P0125, among other things, suggested O2 sensor. I pulled both of them out and found the up-stream heater open so I replaced it with a Bosche universal. It still has the same problem but now I get P0171 errors (mixture too lean). My next thought is fuel filter but it looks like a bear to replace, I might take it to the dealer for that one if you guys think that could be the cause... The car has 90,000 miles, I bought it with 60,000 and don't know if the fuel filter was done before.

Any help would be appreciated.

Thanks
Frank

[ripley's99]

was the timing belt replaced at 60k? along with the water pump?
also has a coolant flush been performed?

if the fuel filter has never been changed, that is something that needs to be done.
as far as the bad exhuast smell have you checked the catalytic convertor?

good luck,
Keri

[sigh]

Thanks for the reply.

I had the timing belt done around 80,000, not sure if it was done by the previous owner. I haven't done the coolant or water pump since I've had it. What's the replacement interval for the water pump? I probably should have had that done when they were in there doing the timing belt.

I bought the fuel filter today and will get that replaced tomorrow, weather permitting. I'll let you know how that goes...

Is there any way to check the catalytic converter short of getting it replaced? What is the life expectancy of the CC, and can it cause these kinds of problems.

Thanks again,
Frank

[ripley's99]

normally the water pump is replaced along with the timing belt since it is right there so to speak. as far as a regular replacement interval i don't know what the exact time is, i don't have my factory service manuals here with me right now, but i would think its about time/getting close to time for that to be replaced soon.

as far as finding out if the catylitic - (cat) is worn out, you can kind of try to move it around and if you hear lots of 'stuff' inside rattling around the bottom of it that means its time to replace it. the material inside just gets worn out and can make the exhaust smell bad.

after talking to my husband here, a few other things that can be done that may help with the power & exhaust smell is clean out your throttle body. you can buy spray throttle body cleaner at pep boys for like $5 spray it in there, clean the grime out with a rag then start the car. the car will smoke on start up at first but this should help.

one other thing to check if you haven't already is the exhaust manifold. check for any cracks/leaks anywhere.

glad to try to help you out

Keri

[SmokingTires]

Well, the fuel filter should be replaced everytime you change your oil. That's why I always change my own. Cause most places won't change the fuel filter.

As for your code, I would guess that your MAF is bad. That would explain the too lean signal.

For the cat, if you have a Gen 3, it is a bolt on, and you can remove it to check.

The smokey smell may mean that your car is burning oil on the engine. That would mean that your car has some minor oil leaks. Have the valve cover gaskets, distributor O-ring, and the rear cam seal checked. They could all be leak spot that you wouldn't really notice.

I just replaced mine, and there was no visible oil leak inside, or on the ground.

Water pumps should be replaced when they leak. I did mine at 177,000.