Vsc / Check Engine Light On / Vehicle Engine Stalled

[92silverls400]

Couple of months ago, I wrote about my engine stalling and not able to accelerate, with the VSC light on also. When I had it checked out couple of month ago thru Lexus dealship, they could not find out what was wrong, and gave me my car back without fixing the problem.

:cries: Last thursday, I drove over 400 miles to Los Angeles, Ca. as I exit the freeway, the check engine light, VSC light came on, and the engine would not accelerate when I stepped on the gas pedal, I coasted across a large intersection, and came to a stop. I then shut off the engine, and restarted it again. and I was able to proceed to my hotel. The next day, I took my Lexus LS400 (2000) to the closes Lexus dealership, which was in Westminister. The check engine light and VSC light was still on. I was not able to find the Lexus Service department, but did fine the Lexus show room, I pulled in and asked the saleman, he told me the service department was 4 blocks away, I restarted my engine, and guess what? The check engine light and VSC light went out. :whistles:

After I arrived at the service department, I told the service writer what had happen, she told me to give her half an hour for the mechanic to check into my problem, about 45 mins later, she told me the problem was the throttle body unit. and would need to be replaced. I asked if it was just the sensor, and she said the whole unit needed replacement. Thank God for my Extended warranty that I had purchase when I brought my Lexus in June of this year. The mechanic took another hour to replace the unit and they also washed my car for me, which really needed after driving over 400 miles. So after couple of months, I have finally resolved my problem with this vehicle.

[nc211]

this is why all of us should take the time to clean our throttle bodies. This is a common problem on these cars, and unless you're throttle body is physically broken, there really is no real reason to ever replace it. You got LUCKY with having that warranty!!! The backside of the butterfly opening of the throttle body "that lets in the air into the engine" gets really nasty and grimmy from miles and miles and miles of driving. This is related to several reasons, but mostly due to our cars having an EGR system, which stands for Exhaust Gas Return. Due to the EPA, our car's engines are fed some of the exhaust back into the engine for another go-around, before being sent out the tail pipe. That exhaust air is nasty stuff, and over time will grime up the inside of the throttle body, back of the butterfly valve, and especially the outter edges of the butterfly valve. Over time it will become so dirty, that it restricts the air flow into the engine, which chokes it out into a stall.... But your way is the best way...aka...have the warranty buy you a new one!!

[92silverls400]

this is why all of us should take the time to clean our throttle bodies. This is a common problem on these cars, and unless you're throttle body is physically broken, there really is no real reason to ever replace it. You got LUCKY with having that warranty!!! The backside of the butterfly opening of the throttle body "that lets in the air into the engine" gets really nasty and grimmy from miles and miles and miles of driving. This is related to several reasons, but mostly due to our cars having an EGR system, which stands for Exhaust Gas Return. Due to the EPA, our car's engines are fed some of the exhaust back into the engine for another go-around, before being sent out the tail pipe. That exhaust air is nasty stuff, and over time will grime up the inside of the throttle body, back of the butterfly valve, and especially the outter edges of the butterfly valve. Over time it will become so dirty, that it restricts the air flow into the engine, which chokes it out into a stall.... But your way is the best way...aka...have the warranty buy you a new one!!

nc211

I had purchased this vehicle in June 2006 w/ 75800 miles on it. brought it from dealership. How would you know if throttle body was dirty, I don't think dealership would take it apart for inspection prior to selling vehicle. I am not a DIY person. :chairshot: this vehicle had gone thru all maintance proceedure, and I guess prior owner and service dealer never talked about cleaning throttle body unit. How many miles would this unit last before you have to clean it out. is their a preventive measure to keep this unit clean?

thanks

[alsalih]

I think folks sometimes forget the many differences that the 98+ LS have over previous models. Your throttle body can and will get dirty but this will not cause the problem you noted. The 98+ LS does not have an EGR system as the earlier ones do, they’re able to reduce emissions through the use of VVT-i. You have an electric motor mounted at the throttle body which controls the throttle, and is most likely what caused your intermittent problem. That still doesn’t justify replacing the complete throttle body, rather the motor assembly only, which runs about $290.

[oohryry]

I think folks sometimes forget the many differences that the 98+ LS have over previous models. Your throttle body can and will get dirty but this will not cause the problem you noted. The 98+ LS does not have an EGR system as the earlier ones do, they’re able to reduce emissions through the use of VVT-i. You have an electric motor mounted at the throttle body which controls the throttle, and is most likely what caused your intermittent problem. That still doesn’t justify replacing the complete throttle body, rather the motor assembly only, which runs about $290.

Question, what is this electric motor. If the code comes up as the TPS, would replacing the electric motor instead of throttle body fix the problem and stop the error code? Do you know this for sure?

[fjstl]

I think folks sometimes forget the many differences that the 98+ LS have over previous models. Your throttle body can and will get dirty but this will not cause the problem you noted. The 98+ LS does not have an EGR system as the earlier ones do, they’re able to reduce emissions through the use of VVT-i. You have an electric motor mounted at the throttle body which controls the throttle, and is most likely what caused your intermittent problem. That still doesn’t justify replacing the complete throttle body, rather the motor assembly only, which runs about $290.

I also have a 98 LS 400 with 97k and no one has ever indicated anything about cleaning the throttle body. Should it be done and at what interval if needed?

[Depot]

I think folks sometimes forget the many differences that the 98+ LS have over previous models. Your throttle body can and will get dirty but this will not cause the problem you noted. The 98+ LS does not have an EGR system as the earlier ones do, they’re able to reduce emissions through the use of VVT-i. You have an electric motor mounted at the throttle body which controls the throttle, and is most likely what caused your intermittent problem. That still doesn’t justify replacing the complete throttle body, rather the motor assembly only, which runs about $290.

Question, what is this electric motor. If the code comes up as the TPS, would replacing the electric motor instead of throttle body fix the problem and stop the error code? Do you know this for sure?

I recently had a TPS replaced on my '99 LS 400 and I'll tell you what my mechanic told me, "TPS malfunction came up on the diagnostics, and this could be caused by one of three things: faulty wiring, a bad computer, or the TPS itself. Since Lexus seldom have wiring issues, and a bad computer would more than likely produce additional symptoms, chances are it's the TPS itself."

So it's more or less a crapshoot. He replaced the TPS and it fixed my problem.