$75
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From: va
$75
Please help me go in the right direction with my 93 ls400 w/140k miles.
When the car is in park the idle fluctuates from 550-700.
When the car is in drive the idle becomes more erratic and fluctuates from 700-300.
When car is driving on the road I can feel the idles drop for a split second then recovers.
My question is I received a $75 coupon from Lexus. I think my ignition timing may be the cause or the idle air control valve or throttle position sensor or my timing belt is worn (it has cracks)
Should I tell them to diagnose the idle problem or go ahead and have them check the timing and adjust if necessary. I only have enough money to do one or the other.
I think the timing may be off because of the condition of the car was bad when I bought it. I changed the air filter, cleaned the throttle body, seafoamed the intake, changed the fuel filter et cetera.
any suggestions would be appreciated.
When the car is in park the idle fluctuates from 550-700.
When the car is in drive the idle becomes more erratic and fluctuates from 700-300.
When car is driving on the road I can feel the idles drop for a split second then recovers.
My question is I received a $75 coupon from Lexus. I think my ignition timing may be the cause or the idle air control valve or throttle position sensor or my timing belt is worn (it has cracks)
Should I tell them to diagnose the idle problem or go ahead and have them check the timing and adjust if necessary. I only have enough money to do one or the other.
I think the timing may be off because of the condition of the car was bad when I bought it. I changed the air filter, cleaned the throttle body, seafoamed the intake, changed the fuel filter et cetera.
any suggestions would be appreciated.
Last edited by neostar43; Nov 15, 2010 at 07:29 PM.
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From: tx
i just did the same on my 93 lexus ls400 137,000
the timing is not so hard
if your considering doing it yourself what ever you do do not mess with any other components like spark plugs especially not the throtle body and injectors like that if something does go wrong you dont have to put any other variables in
ooohhh and buy gates parts if DIY i bought ebay stuff its crap
still ended up buying gates
duralast is the same thing as ebay
the timing is not so hard
if your considering doing it yourself what ever you do do not mess with any other components like spark plugs especially not the throtle body and injectors like that if something does go wrong you dont have to put any other variables in
ooohhh and buy gates parts if DIY i bought ebay stuff its crap
still ended up buying gates
duralast is the same thing as ebay
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From: va
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From: ct
The $75 coupon you have, is it like cash or do you have to spend to save? The timing can't be adjusted. If there is no way for you to figure out the problem without throwing part after part at it, do to finances, have them diagnose it for you. And then, if it can wait, fix it when you do the timing belt in January when you can afford it. That's what I'd do b/c I know how money can be tight.
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From: va
The $75 coupon you have, is it like cash or do you have to spend to save? The timing can't be adjusted. If there is no way for you to figure out the problem without throwing part after part at it, do to finances, have them diagnose it for you. And then, if it can wait, fix it when you do the timing belt in January when you can afford it. That's what I'd do b/c I know how money can be tight.
I have a new fuel pump and used tps hopefully it is linked to these issues so I do not have to put out more money
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Let us know how it turns out.
My 1994 Lexus behaves the same way, but only when I'm using the air con.
Since this is my first car, I do not have any references, so I'll have to believe my mechanic when he tells me that that is the expected behavior when using the air con. I'm skeptical though ;-)
BJL
My 1994 Lexus behaves the same way, but only when I'm using the air con.
Since this is my first car, I do not have any references, so I'll have to believe my mechanic when he tells me that that is the expected behavior when using the air con. I'm skeptical though ;-)
BJL
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From: va
i live in va beach, va. i may just swap the used tps with the one on the car to see if I get any different reactions.
I don't understand why seafoam would cure the problem for one drive then it gradually came back.
also, when I first start the car and is in high idle the rpms do not jump around. just after it starts to warm up does it occur
I don't understand why seafoam would cure the problem for one drive then it gradually came back.
also, when I first start the car and is in high idle the rpms do not jump around. just after it starts to warm up does it occur
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From: va
i've been doing some more research. it is funny the things you overlook until someone points it out.
A couple of nights ago, I tried to push the car. the rev did not go past 4000 rpms.
after reading an old post, I am going to clean the maf. This maf is actually a replacement for the one that was originally in the car when i bought it.
The erratic rpms was there a couple weeks after I bought the car but went away after i cleaned the tb and replaced the maf and installed a k&n filter. after awhile the problem became worse that is when i noticed that my power steering resevoir was empty. refilled it and problems went away mostly. but then the problems came back. my power steering resevoir has not needed a refill. i disconnected the acv from the ps pump from the intake. that has made no difference. so I will reconnect the lines and clean the maf and see what happens.
is there a particular cleaning solution that is used for the maf that is safe for lexus?
A couple of nights ago, I tried to push the car. the rev did not go past 4000 rpms.
after reading an old post, I am going to clean the maf. This maf is actually a replacement for the one that was originally in the car when i bought it.
The erratic rpms was there a couple weeks after I bought the car but went away after i cleaned the tb and replaced the maf and installed a k&n filter. after awhile the problem became worse that is when i noticed that my power steering resevoir was empty. refilled it and problems went away mostly. but then the problems came back. my power steering resevoir has not needed a refill. i disconnected the acv from the ps pump from the intake. that has made no difference. so I will reconnect the lines and clean the maf and see what happens.
is there a particular cleaning solution that is used for the maf that is safe for lexus?
I have a 1993 that just hit 280000kms. It does the exact same thing once and a while. I also put in a K&N drop in filter. Make sure not to over OIL the filter as it does get stuck in the MAF. Doesn't hurt to clean it out but be gentle.
As for the power steering if it continues to use fluid then it's the IDLE AIR CONTROL VALUE . You can figure this out when your driving around 60mph or so the steering should be more stiff where as on low speeds should be loose. This is a common problem with 1st gen LS
https://www.clublexus.com/forums/ls4...ing-bible.html
IF you tried changing the IDLE AIR CONTROL VALUE and still doesn't work there is TPS (throttle position sensor)
I had to replace both and the idle is totally normal unless the A/C is on. That's my advice.
As for the power steering if it continues to use fluid then it's the IDLE AIR CONTROL VALUE . You can figure this out when your driving around 60mph or so the steering should be more stiff where as on low speeds should be loose. This is a common problem with 1st gen LS
https://www.clublexus.com/forums/ls4...ing-bible.html
IF you tried changing the IDLE AIR CONTROL VALUE and still doesn't work there is TPS (throttle position sensor)
I had to replace both and the idle is totally normal unless the A/C is on. That's my advice.