VSC & Check Engine Lights 2001 RX300
CL Community Team
Joined: Apr 2004
Posts: 17,338
Likes: 213
From: Miami, Florida
Lead Lap
Joined: Jan 2002
Posts: 412
Likes: 1
From: S. Dakota
sorry about bringing up an old post.
My 01 starting having the check engine and vsc light issue. It seems odd though as it comes and goes. it was on for 2 days then off for a few weeks then back for a day and now off again. All at different times of the day and fuel levels. The code from autozone suggested a fuel cap or oxygen sensor issue, I have not changed either. Any other ideas on why this comes and goes.
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My 01 starting having the check engine and vsc light issue. It seems odd though as it comes and goes. it was on for 2 days then off for a few weeks then back for a day and now off again. All at different times of the day and fuel levels. The code from autozone suggested a fuel cap or oxygen sensor issue, I have not changed either. Any other ideas on why this comes and goes.
e
Lead Lap
Joined: Apr 2006
Posts: 490
Likes: 2
From: NJ-Exit 105 PKWY
I also have the check engine and vsc light. I took it to AutoZone for a readout and got code P1155. I had the guy clear it with the reader, came back 1 min after. The guy said it was the air/fuel ratio sensor heater circuit malfunction (bank2 sensor 1)
Probable cause are:
1:Open or short circuit condition
2:AF sensor heater relay fault
3:Failed AF ratio sensor
This is my first time getting a CEL. I have a 2001 with 66,666 <---Bad Luck huh.
What should I try to fix first? Thanks
Probable cause are:
1:Open or short circuit condition
2:AF sensor heater relay fault
3:Failed AF ratio sensor
This is my first time getting a CEL. I have a 2001 with 66,666 <---Bad Luck huh.
What should I try to fix first? Thanks
CL Community Team
Joined: Apr 2004
Posts: 17,338
Likes: 213
From: Miami, Florida
Likely issue is the A/F sensor itself (this is the one easily visible on the front exhaust manifold when you open the hood). Even if you check resistances and connections, almost inevitably the sensor is bad and needs replacement.
Lead Lap
Joined: Apr 2006
Posts: 490
Likes: 2
From: NJ-Exit 105 PKWY
Thanks Lexmex,
Are there any precautions I should take while trying to remove the A/F sensor? This way I wont do any damage costing more than expected. And if it does not fix the problem, what is my next step?
Are there any precautions I should take while trying to remove the A/F sensor? This way I wont do any damage costing more than expected. And if it does not fix the problem, what is my next step?
CL Community Team
Joined: Apr 2004
Posts: 17,338
Likes: 213
From: Miami, Florida
I'll defer to those who have actually changed to A/F sensors on the RX300 (which I have yet to do), but if you still have the problem we can recheck the code again. Sometimes it is the installation or connection when there still exists a problem.
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CL Community Team
Joined: Apr 2004
Posts: 17,338
Likes: 213
From: Miami, Florida
Most likely thing here is the A/F sensor shown here (behind the engine). Secondary possibility is that the harness/connector either here where shown or where the wire leads to is loose (that can happen with the amount of heat generated here over time). The odd man out here is the ECM (vehicle computer, but highly doubtful). In the past, almost everyone ended up having to replace this sensor
CL Community Team
Joined: Apr 2004
Posts: 17,338
Likes: 213
From: Miami, Florida
You just have to take a look under there and see if there are no splices in the wires. I swore I had a picture of where the connector (wire going to the right in the photo) goes to, but that would be the other point to check out to see if it is loose. I'll try looking again, but I didn't see it in my folders.
OK P0128 was the code and here was the explaination
Check coolant level
Thermostat defective
ECT sensor defective
So I bought the thermostat and ECT - are they easy to install ? Help me if you can, any advice is appreciated. It was $50 for the two parts ..... so hopefully this works
Also I actually noticed my car was running cooler than it usually does.
Check coolant level
Thermostat defective
ECT sensor defective
So I bought the thermostat and ECT - are they easy to install ? Help me if you can, any advice is appreciated. It was $50 for the two parts ..... so hopefully this works
Also I actually noticed my car was running cooler than it usually does.
2nd question: Any supplier recommendations for a TRD thermostat if it's necessary? What will I gain?
Thank you!!!
CL Community Team
Joined: Apr 2004
Posts: 17,338
Likes: 213
From: Miami, Florida
In most vehicles, the sensor should be checked out first. When we have gotten this code at the shop on other vehicles, often times we just change out the coolant (since most people hardly change it at all until it is too late) and then see what is going on after that, since sometimes old coolant can cause issues with the t-stat.
Also make sure your cooling fans are coming on and not overunning, eventually they should turn off at certain points.
Easier place I found to get that t-stat is our CL sponsor, Carson Toyota, http://www.l-tunedparts.com/model/st...id=19&cat_id=1
However, I recommend if you get that to also get the Tom's Radiator Cap, too, and add a bottle of WaterWetter from Redline or Royal Purple's Purple Ice.
That combination will drive the engine temp's to midline or below. It gets me a bit more quality time on the track, instead of the engine heating up after a few runs.
Also make sure your cooling fans are coming on and not overunning, eventually they should turn off at certain points.
Easier place I found to get that t-stat is our CL sponsor, Carson Toyota, http://www.l-tunedparts.com/model/st...id=19&cat_id=1
However, I recommend if you get that to also get the Tom's Radiator Cap, too, and add a bottle of WaterWetter from Redline or Royal Purple's Purple Ice.
That combination will drive the engine temp's to midline or below. It gets me a bit more quality time on the track, instead of the engine heating up after a few runs.
