2000 Celica Engine light

[YeeKung]

Hello,

I've been reading posts about check engine lights, with code PO172 and I have the same problem. I've been having trouble codes PO172 and PO175 setting (now PO172) for the past year. Also, the car would idle roughly, exhaust vibrate, when I'm at a stop light. To stop this, I would put the car in neutral or press on the gas a little. Sometimes the car would hesitate when I accelerate from a stand still. The first time the check engine light came on, I had PO175 and my dealer told me because I was low on oil. I'm no mechanic expert, but I found it hard to believe. I had the oil change and all was fine for awhile. Since then, the check engine light has gone on and off and in the last 6 months, now stayed on. I've had my spark plugs and air filter changed. After reading many posts, I cleaned the MAF sensor with electronic cleaner yesterday and the car would idle much more smoothly and no hesitation. After driving the car for 13 km (8 miles) the engine light came back on today and is still on. Hesitation has come back too. A mechanic told me that it is possible that I have a blockage in my exhaust system, possibly muffler, that would cause the hesitation. I'm thinking of changing the muffler, but I would like to make sure it is a cause of my problems (or some). I'm also thinking of changing the O2 oxgen sensor too, but a lot of posts says it is not likely the culprit. Everything in my car is stock, no performance parts of anykind. Any help would be greatly appreciated.

Thanks.

[needinhelp]

My '00 celica did this awhile back. It took several things replaced to fix this issue. Replacement of the 02 sensor, replacement of all 4 fuel injectors. This did fix the problem. No hesitation at take off, no rough running. It was a little expensive, but well worth it.

[hit_em]

sorry I dont have advice for ya, but I am haveing a similar problem only mine only hesitates when it cold. after you press the gas for about 10 seconds it goes away and runs great, anyone know the problem for this?

[Kathlayne]

(I'm sorry if I make mistake in english, i'm from Quebec and I'm not very good in english :P)

I have the same problem with my celica 00. My car hesitates all the time but more when it cold. I have clean my injector twice but it has just help for ... 2 hours ? I try my car withou the first O2 sensor and it wasn't the problem so I think that is not the catalyseur (?? Exhaust ...). I changed my spy plug and my mass air flow have been clean. But my car continue to have problem ... I don't know what to do and I hope someone can help me ..

Thanks !

[diablito1975]

Originally Posted by Kathlayne

(I'm sorry if I make mistake in english, i'm from Quebec and I'm not very good in english :P)

I have the same problem with my celica 00. My car hesitates all the time but more when it cold. I have clean my injector twice but it has just help for ... 2 hours ? I try my car withou the first O2 sensor and it wasn't the problem so I think that is not the catalyseur (?? Exhaust ...). I changed my spy plug and my mass air flow have been clean. But my car continue to have problem ... I don't know what to do and I hope someone can help me ..

Thanks !

did your check engine light came on?

[Kathlayne]

My check engine ligth have been removed, but in the computer, it said that the ligth is on.

[diablito1975]

Originally Posted by Kathlayne

My check engine ligth have been removed, but in the computer, it said that the ligth is on.

if the light was removed but the computer showed it wsa on i am assuming you were using a scanner if so did you get a trouble code ?

[damp]

im having the same problem when idleing, would bog the go. check engine light came on and said o2 sensor and was running rich as well.
im going to change the o2 sensor and hopefully it works but was wondering if the GT AND GT-S model are the same senors?