cel HELP!
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From: mo
cel HELP!
I test drove a lexus rx300 1999 .I live th features and look of the car itself.I drove it home for a few days to test it out .Its a biut 45 min drive from where im purchasing it.Anyway the check engine light was on so i took it to autozone it code# p0171 so i cleaned the maf it had buildup on it although i forgot the 2 strings inside,i reset light it went off but came back on 
I also noticed a clunking noise when i hit a bump on front passenger sideby the wheel not sure wht tht could be.So anyway i take it back 2 days later and hit the highway it doesnt shift into overdrive...hmmm but as soon as i get there its fine.We took it back on highway never had a problem with it...So i guess mt questiin is to everyone is should i purchase it?It has 160,000 miles and looks great for only 3500.00. It sounds like an awesome price but im a gal and dont know to much just a lil....
I also noticed a clunking noise when i hit a bump on front passenger sideby the wheel not sure wht tht could be.So anyway i take it back 2 days later and hit the highway it doesnt shift into overdrive...hmmm but as soon as i get there its fine.We took it back on highway never had a problem with it...So i guess mt questiin is to everyone is should i purchase it?It has 160,000 miles and looks great for only 3500.00. It sounds like an awesome price but im a gal and dont know to much just a lil....
Lexus Test Driver
Joined: Aug 2009
Posts: 5,723
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From: NJ
You will need a knock sensor from the sounds of it, because you said you weren't able to get into overdrive. Try to shoot for $3000, even though 3500 is still an awesome price. Or get the seller to include the repairs.
Lexus Champion
Joined: Nov 2005
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From: OH
Lexus Test Driver
Joined: Aug 2009
Posts: 5,723
Likes: 114
From: NJ
The MAF or A/F sensor won't stop the RX from going into overdrive. The knock sensor can. I'm not saying it is the knock sensor, but it's a possibility. The OP did state it's going into overdrive now though, so we don't really know unless there's a CEL.
Lexus Champion
Joined: Nov 2005
Posts: 2,110
Likes: 77
From: OH
I'm pretty sure that if you are in limp mode it will not go into O/D. So an A/F sensor that has failed and kicked it into limp mode will lock out O/D. Failed knock sensors always seem to put it in limp mode, but other faults can too. I think it just depends on the severity. like a shorted A/F sensor heater, will not.
CL Community Team
Joined: Apr 2001
Posts: 16,559
Likes: 1,385
From: Austin, TX
I test drove a lexus rx300 1999 .I live th features and look of the car itself.I drove it home for a few days to test it out .Its a biut 45 min drive from where im purchasing it.Anyway the check engine light was on so i took it to autozone it code# p0171 so i cleaned the maf it had buildup on it although i forgot the 2 strings inside,i reset light it went off but came back on I also noticed a clunking noise when i hit a bump on front passenger sideby the wheel not sure wht tht could be.So anyway i take it back 2 days later and hit the highway it doesnt shift into overdrive...hmmm but as soon as i get there its fine.We took it back on highway never had a problem with it...So i guess mt questiin is to everyone is should i purchase it?It has 160,000 miles and looks great for only 3500.00. It sounds like an awesome price but im a gal and dont know to much just a lil....
I also noticed a clunking noise when i hit a bump on front passenger sideby the wheel not sure wht tht could be.So anyway i take it back 2 days later and hit the highway it doesnt shift into overdrive...hmmm but as soon as i get there its fine.We took it back on highway never had a problem with it...So i guess mt questiin is to everyone is should i purchase it?It has 160,000 miles and looks great for only 3500.00. It sounds like an awesome price but im a gal and dont know to much just a lil....In some counties, the vehicle with a CEL on is considered unfit to be on the road. If you are buying the vehicle off a lot, the seller should know this. Private sales are different. If you are serious, then it would be prudent to get the service history form Lexus dealership. I would suggest that you take the vehicle to a place where they have a lift and have the suspension examined.
So what code are you getting now? If it is the same one then you may like to replace it. There are cases where even after replacing the meter the problem persisted and more parts had to be replaced. Search on P0171.
Salim
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From: mo
I guess the thing to do would change the maf sensor and go from there.Im not quite sure where the af sensor is and how to change it.If anyone has illustrations on that it would be great.Can you clean the af sensor or does it just have to be changed?Thanks again for all your help.I hate to pass this car up cuz its a great price.
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Lexus Test Driver
Joined: Aug 2009
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From: NJ
Don't change the A/F sensor. Or, yet anyways.
You don't have a code for it. It's not worth throwing parts at it. Once you get a code, we can find out which A/F sensor it is. < That is if you do get a code...
You don't have a code for it. It's not worth throwing parts at it. Once you get a code, we can find out which A/F sensor it is. < That is if you do get a code...
Thread Starter
Rookie
Joined: Oct 2011
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From: mo
I guess the thing to do would change the maf sensor and go from there.Im not quite sure where the af sensor is and how to change it.If anyone has illustrations on that it would be great.Can you clean the af sensor or does it just have to be changed?Thanks again for all your help.I hate to pass this car up cuz its a great price.
CL Community Team
Joined: Apr 2001
Posts: 16,559
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From: Austin, TX
Thread Starter
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Joined: Oct 2011
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From: mo
I cleaned the maf and reset it the light went out and stated out till i restarted it and then it came back on and about 2 more starts after that it went off and stayed off for maybe a day or two.now its on and has stayed on.