12-16-14, 01:04 PM
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Intermittent loss of power
08-01-12, 08:34 AM
#17
Lead Lap
Thread Starter
Brian.......Thanks very much for finding out the actual part you replaced. I'll call Lexus to find out the price of the part and prepare myself in case the car becomes symptomatic again. Thanks again.
08-10-12, 07:41 PM
#18
OK, techron won't do a thing. MAF could have an intermittent short but should throw a code.......THE REAL ANSWER. ......glancing through the posts i've already seen it. accelerator pedal position sensor. could also be throttle position sensor but the acc pedal sensor is more common. you will need an oscilloscope to confirm. if not, you'll just have to try it.
08-10-12, 07:47 PM
#19
Lead Lap
Thread Starter
OK, techron won't do a thing. MAF could have an intermittent short but should throw a code.......THE REAL ANSWER. ......glancing through the posts i've already seen it. accelerator pedal position sensor. could also be throttle position sensor but the acc pedal sensor is more common. you will need an oscilloscope to confirm. if not, you'll just have to try it.
10-04-14, 01:04 PM
#21
Lead Lap
Thread Starter
I am the originator of this post. My 2001 LS430 now has 115,000 miles. My hesitation on acceleration is still a problem and is happening more often. I took my car to Lexus yesterday and had a diagnostic tech check for any history of possible faults. Nothing came up. We then went for an extensive drive with his lab top hooked up to my car. Of course the car behaved perfectly with no hesitation. I have no clue as to the problem and of course will not be replacing parts needlessly. The tech told me the only issues he has had similar to mine were with a 2004 model that needed a fuel pump replacement. All I can do at this point is wait until it gets worse or until the check engine light comes on. Anyone else out there with a similar problem? I've been living with it for over 2 years, but it seems to be happening more frequently. . Thanks all.
10-05-14, 06:52 AM
#22
boca trip
sorry to hear your having issues, sounds like your frustrated
reach out to me with a private message if you need some good mechanics in south florida to take it too. there are a select few to trust and just want to make sure your taken care of.
safe driving
reach out to me with a private message if you need some good mechanics in south florida to take it too. there are a select few to trust and just want to make sure your taken care of.
safe driving
10-07-14, 06:10 AM
#24
Lead Lap
Thread Starter
Lavrishevo...I asked that very question. Can the "drive by wire" parts be tested?. He said that if they are behaving at the time of testing, nothing will show up.
10-16-14, 07:38 PM
#25
Driver School Candidate
You're gonna laugh...
For about three years, my 2001 GS 430 has been having intermittent loss of power, usually at slow speeds (but not always), like the gas pedal was dead for short periods of time, never any warning lights. I had the local dealer keep it for several days at one point, but they had no suggestions. Recently, I noticed that it never did the behavior while operating under cruise control. I started thinking what would make the car not lose power when under cruise control. What system would not be in use, or might be ignored by the car, when the car was under cruise control? Here's what I came up with, like some others on this forum... accelerator pedal position sensor. I checked into it, and the best estimate I could get was to replace it for about $400. I did some research on that part and learned that it is potentiometer, a mechanical one. I remembered that years ago, I had an old Marantz receiver which had volume controlled by potentiometers that from time to time would start getting "dead spots". The cure was to manually rotate the **** multiple times, rather forcefully, to clean out whatever might be causing the dead spots. I usually worked! So, I climbed under the dash of the GS430 and forcefully banged on the accelerator pedal, about 100 times, thinking that it might make that potentiometer work correctly. Believe it or not, IT WORKED! No more intermittent loss of power. And it was FREE! Don't know if it would work in every case, but it worked for me. Good luck....
Update: 15 months later, no recurrence of the problem... Yea!
Update: 15 months later, no recurrence of the problem... Yea!
Last edited by Crumvoc; 03-09-16 at 09:41 PM.
10-17-14, 06:04 AM
#26
Wow, 8,000 miles in 2 years is very low use. I would not overlook a transmission issue too. Seems like you are dealing with a part throttle issue and the engine might be having issues communitating to the tranny delaying a downshift or something.
10-18-14, 01:23 PM
#27
Lead Lap
Thread Starter
For about three years, my 2001 GS 430 has been having intermittent loss of power, usually at slow speeds (but not always), like the gas pedal was dead for short periods of time, never any warning lights. I had the local dealer keep it for several days at one point, but they had no suggestions. Recently, I noticed that it never did the behavior while operating under cruise control. I started thinking what would make the car not lose power when under cruise control. What system would not be in use, or might be ignored by the car, when the car was under cruise control? Here's what I came up with, like some others on this forum... accelerator pedal position sensor. I checked into it, and the best estimate I could get was to replace it for about $400. I did some research on that part and learned that it is potentiometer, a mechanical one. I remembered that years ago, I had an old Marantz receiver which had volume controlled by potentiometers that from time to time would start getting "dead spots". The cure was to manually rotate the **** multiple times, rather forcefully, to clean out whatever might be causing the dead spots. I usually worked! So, I climbed under the dash of the GS430 and forcefully banged on the accelerator pedal, about 100 times, thinking that it might make that potentiometer work correctly. Believe it or not, IT WORKED! No more intermittent loss of power. And it was FREE! Don't know if it would work in every case, but it worked for me. Good luck....
Last edited by Bocatrip; 10-18-14 at 01:26 PM.
10-18-14, 01:57 PM
#28
Driver School Candidate
Hope it stays fixed!
In opposition to my method, you might try just "ranging" the pedal from stop to floor multiple times without the "banging" part. Might be just as effective, or not...
UPDATE: Still no intermittent loss of power after 8 days and about 450 miles. Crossing my fingers.....
Update #2: Going on a month and no intermittent power loss still! Yes!
Last edited by Crumvoc; 11-05-14 at 10:31 PM.
06-08-15, 12:18 PM
#29
Driver School Candidate
Recently, I acquired a '03 Lexus GS430 with roughly 118k miles on it. I am experiencing a similar intermittent loss of power issue as many others are describing here. It is worst in the morning when I start the car and seems to be getting worse slowly but surely.
I have these symptoms for about 10 minutes before it gets better. It typically occurs at a standstill trying to accelerate.
I don't have any check engine lights. From what I gather on this forum, it's most likely that it is a faulty TPS (Throttle Position Sensor) or APPS (Accelerator Pedal Position Sensor). I see these parts for sale on eBay. The aftermarket TPS are considerably cheaper ($29) than the OEM part ($70). Is it ok to go with the aftermarket ones? Has anyone had any issues with those?
I have these symptoms for about 10 minutes before it gets better. It typically occurs at a standstill trying to accelerate.
I don't have any check engine lights. From what I gather on this forum, it's most likely that it is a faulty TPS (Throttle Position Sensor) or APPS (Accelerator Pedal Position Sensor). I see these parts for sale on eBay. The aftermarket TPS are considerably cheaper ($29) than the OEM part ($70). Is it ok to go with the aftermarket ones? Has anyone had any issues with those?
12-03-15, 12:05 PM
#30
Lexus Test Driver
Darnit, I've got these symptoms now. Car feels like it's towing a trailer, really unresponsive, hesitant to downshift under throttle and holds the lower gear too long when I release the throttle. Feels like I'm driving a city bus. Strangely this dullness kicks in after about 10-15 minutes of driving, and it started immediately after filling the tank with fresh gas. Boca have you rectified this problem yet?