Major problem with car, please help

[holmes182]

I have a 1999 Toyota Solara 3.1L V6 Automatic. I just drove home from work and the check engine light came on. The car shakes and pulls when I go over 45 mph with the intensity of the shaking and pulling rising as I go faster and their is a strong exhaust smell in the car. It almost feels as if its sputtering at the higher RPM's. I just put a new tank of gas in my car. Do you think its bad gas? The transmission seems like it is slipping when the car is shifting from 2nd - 3rd and 3rd - drive. Not from drive to overdrive though. I popped the hood and looked under the car. Everything seems to be in order. Nothing out of place. Thanks guys, I appreciate any help on this matter.

[BadChicken]

First off its a 3.0L, second you should have the code read and find out why the check engine light came on, then we can probably give you some insight on the matter

[holmes182]

The codes are P0300 - Random/Multiple Cylinder Misfire Detected and P0171 - System too Lean (Bank 1).
He said I needed a tune up and if that doesn't work then it could be an oxygen sensor. I was thinking possibly the CAT Converter b/c of the strong exhaust smell in the car. And if the CAT went out then the back pressure would cause the engine to sputter, right? What do you all think is the problem? Thanks guys for your help.

[BadChicken]

usually a p0171 code indects a bad mass air flow sensor or a vacuum leak
I would check into this first

[holmes182]

gents, i got a tune up (replaced the plugs and wires) and it fixed the problem

[holmes182]

it happened again, so I took it back to the mechanic, got it read, needed an O2 sensor, got it fixed, that was saturday, now its wednesday and it happened again, this time the exhaust smell is very bad inside the car, and the shaking has gotten worse, its at its worst when i'm going 50 mph, the car is shaking and pulling and pushing, the check engine light came back on, this is the 3rd time in less than a month that it has done the same exact thing, is my mechanic ripping me off or something? my father said he thinks the problem is the catalytic converter, anyway I am taking into the mechanic and will let u all know what the code is, thanks

[UltraslowSolara]

a broken cat does not effect your performance. and i think your mechanic is ripping you off by just simply reset the ecu to make you think he fixed the car.

bad exhaust smell - it might be that you are burning some engine oil

i think you just have a dirty or bad mass flow air sensor becasue it sounds like it. (having hard time to raise to certain rpm)

or it sounds like a bad coil pack

however, i would recommend you take it to another mechanic. your mechanic sucks

[SolaraTRD]

yeah, that mechanic sounds really bad. "A tune-up" no-no-no...

If you're going to get the codes read, might as well take it to the dealership. They pin-point EXACTLY what part or problem is causing the CEL & malfunctioning. Anywhere you go, to get a full diagnostic, it cost from $70 (pep-boys I think) to $80 (dealership)

might as well know exactly whats wrong with it, then testing all these parts out... Disconnecting the battery and reconnectnig it resets the ECU. It'll take some time (couple days to a week) for the computer to pick up the bad stuff and CEL comes on again.

good luck

[WortownSolara]

Please take some of their advice. Most of us have had issues and have gone through some issues that are similar. Save yourself some money now, have the dealership do the diagnostic. But dont necessarily have them do the repair. It may be easy enough for you to do with some advice.

[holmes182]

ok took it to another mechanic (who i've taken my cars to for the past 6 years and konw on a personal level) and he read it and said the fault was Lean 1 (or bank 1) meaning that it was an oxygen sensor, this one i trust, i explained to him that i just had the oxygen sensor replaced and he said well was it the top or bottom one b/c there are 2 on ur car, so i called up the place that did the repairs before and he said that they replaced the top one, long story short, the same mechanic that supposedly did the other repairs is doing this one again, they are replacing the bottom oxygen sensor on it, i trust the place i've been taking my car too b/c i know 2 of the guys that work there, and i know they know there stuff, but this is the last straw, i'm losing patience quickly, i will take your advice on this if something else happens to the car and bring to to the toyota dealership, although i dont know if it would make it or not down to newark, de, the car is putting (lol) very badly

[holmes182]

just got it back, they replaced the 2nd (lower) oxygen sensor, the car is running now, however it isnt back to 100 %, i have lost noticeable acceleration in the past month and the car shakes still very slightly (so slight that another person wouldn't be able to tell, however since i'm used to the car i can tell) it was doing the same exact thing after the other 2 times i got it back, so i will wait till the check engine light comes on again and will take it to the toyota dealership to find out exactly what is wrong, also to those who said that they are just clearing out the CEL, i know that they arent doing that b/c i had it cleared today to see if it would correct the problem and it was doing the same thing with it off, so i know they are fixing it, or at least attempting to, lol, also i have one more question, when i bought the car in july 2004 i was told only to put premium in it, and i did up until april 06. i then switched back to regular, does anyone think that this could be the problem? i drove maybe 20k on the car during that time frame

[marc780]

Hey holmes! I dont think running regular hurts the car, i have a camry V6 2002 and i run nothing but. No problems. If it makes you nervous not to, just run half and half, buy premium only every other time.
You may be on the right track, a strong exhaust smell could be caused by an overheating cat converter, or an exhaust leak but im assuming they would have found this? when they fixed your car the last time. And this might not necesarily show up when pulling the codes. But if your exhaust pulse from the tailpipe is especially weak, it could be a sign of a plugged converter.
But if it has to go to toyota, then hopefully they will have someone with the expertise to find the issue.

[WortownSolara]

The worst thing thats going to happen now, is you pay for a diagnostic. You come back online here. Tell us what they said. Then im sure a handful of people will tell you if you should attempt it yourself or not ^^

[SolaraTRD]

Originally Posted by holmes182

also to those who said that they are just clearing out the CEL, i know that they arent doing that b/c i had it cleared today to see if it would correct the problem and it was doing the same thing with it off, so i know they are fixing it...

That made no sense to me... The "same thing" was happening "with it off." I don't think that explains if they fixed it, or attempted to fix it. Lol. But, assume they did, which I am in this case...

Like I said earlier in the post. When your mechanic fixes the part, resets the ecu, the CEL will defiantly turn off. The car WILL run a bit wierd for a couple of days upto a week... reason being, the ecu was resetted and now needs to learn your style of driving, Fuel & air mixture, etc etc over time... once the ECU has learned and adjusted, (hopefully) your car will be back to normal.

IF, the mechanic attempted to fix the car, but it didn't work, the car will run rough for a bit, then that CEL will come on again.

Last: Don't mix fuels. Your car's ECU adjusts to premium gas detonation and then you change it to really low octane, the car has to readjust again... it doesn't happen over night and over time, it does damage your car's engine. besides, running on high octane for a non-turbo/high-compression engine will make you lose gas mileage.