GSquicksilver

I'm just getting freakin annoyed by the rough idling in our cars. I can't believe that the dealers keep on telling me that it is "normal" that our cars idle like this. I think it's just BS. They don't want to fix it cuz our cars are still under WARRANTY. They rather have us come back after our warranty is expired and then tell us that our cars don't idle normally and then charge us an arm and a leg. So what do you guys say? Would you have bought ur GS4 if you knew about the rough idle issue?

bitkahuna

iTrader: (20)

Sorry to hear about all these rough and low idle problems... I'm wondering if this is more a problem with '98s because that's all I read about them related with. I don't have any problem on my 2000 with 30K mi. on it now. Idle is fine with and without A/C on, cold or hot.

You'd think it would be a problem with the LS400 too since it has the same engine... maybe ask on the LS400 board?

Synergy

Yo quick - I agree the low idle is totally annoying and lame, but the GS4 is one awesome ride aside from a couple minor rattles and a low idle.

Collectively, we need to pinpoint the low idle issue and convince our dealers to fix the issue!!

Likecars

I just sold my 95 LS400, 68K. Occasionally it would have a dip in RPM. You are probably drawing a comparison between the 98 LS, just thought I'd throw that out there.

NOW I am driving a 99 GS400 NAV/XENON! It just keeps getting better. Have not noticed any rough idle yet, but it may take awhile to notice anything wrong with this car!

GSquicksilver

i'm glad you guys all feel this way. well, i currently have an appointment to see the dealer some time next week for them to check my car out. this will be the second dealership i'm going to. now if they tell me that this is "normal" and that these cars idle like this, then i plan on writing to lexus corporate headquarters about this. i don't think anyone would buy a brand new car that idles rough, would you? heck, even my old '87 toyota cressidle idles smoother than my gs.

bryanb124

LISTEN...THIS IS A MAINTENANCE ISSUE...CLEAN YOUR THROTTLE BODY AND MASS AIR FLOW SENSOR!!!!!!!!!!!

If you take care of your car and do maintenance on it, you won't have this idle issue...this is the same thing as if you had a carbeurated engine...you had to shoot some carb cleaner down it once in a while...well with a fuel injected car that uses a MAF you have to clean the sensor off and should clean the throttle body up...

Now if you have any other problems, then have the dealer inspect your throttle position sensor...this is a dealer adjustable or replaceable item...

I don't mean to be a *****, but this whinning has to stop...you have to maintain your car if you want it run like it was brand new...this is no different than changing the oil or the air filter...except with this item, you should clean it about once every 30k if you use a standard air filter and every 10k if you use an oiled performance filter such as K&N, TOMS, TRD, or Amsoil...

'nuff said...

Bryan

GS400_PUSHER

Man I never thought of that....If I were you I would check that out too before you take it to the dealer!

GSquicksilver

bryanb124,

then were the heck is the mass air flow sensor and how do you clean it? anybody?

GS4Will

to me, really not that big of a deal..annoying, yes....BUT i have experienced worse on more expensive cars..it is true that my 79 4 banger accord idlled smoother sometimes than the GS...

BUT, it all depends on which dealer/service consultant/tech guy takes care your car...my tech guy, Ted from Longo was the one who actually pointed out to me that my car was running/idlling a bit rough when he and i were test driving for other matters...so, he went ahead and took care the rough idlling part with no sweat..btw, my is 99 with 38k miles..

bottomline, no car is perfect...i still have hugh confidence in toyota/lexus...my bmw tranny went dead on me @~50kmiles on the FWY and all the cars were passing by like crazy...while i was on a date..that is where i draw the line...:eek:

ShowGSLuVv

ok I have to ask a question now, When u mean rough idle? is it just very low? or does the car shake very slightly, or does it shake really bad, I get a lil shake in my car that is so slight that u can't notice it till u stop and sit for a second then u can feel it a little, im just curious if my car is idling the same as urs?

ShOwGS

tinygs

Well, thats what I was about to say.....
These threads seem to have started surfacing very recently. From what Ive read this problem has only affected the 98's to date.....
I personally noticed it for the first time somewhere between the 35 and 40k mile mark..... Strange indeed, but the car runs like a champ!!! Low idle occures VERY seldom, and the car doesnt feel like its going to stall whatsoever.....

Oh and one more thing.......I am totally unconvinced that cleaning the throttle body is the cure for a low idle.....I think its only a short term treatment for the symptom........

tinygs

I totally disagree....................

I will challenge anyone on this board to show me an owner who puts more into upkeep than I do....especially engine clenliness....I clean the engine every time I wash/wax my car, as do many other CL members with 98's... Ive cleaned the throttle body and inspected the MAF as recently as two weeks ago, and my SRT filter looks like new........ I also change my own oil and filter(mobile 1 syn.) every 4k.
This is a problem that is effecting MANY 98' owners, alot of whom take extreme pride in keeping their cars prestine inside and out.....
The above problem you described is NOT the root of the problem...

bryanb124

tinygs:

I now refer to my third point...have you had the dealer inspect your throttle position sensor?????

Regardless, I have posted this before:

If you use a performance air filter that requires oil YOU HAVE TO BE SURE YOU DO NOT OVER OIL IT!!!! Over oiling your performance air filter is the sure cause of your problem. I beleive right now that if we took a poll, the majority of people who are having this idle problem are running a performance air filter.

The "More is better" solution does not work with performance air filters...if you over oil them, the oil will be sucked up through the air passage resulting in three problems:

1) oil all over the air intake passage ways that always ends up on your MAF sensor

2) oil all over the throttle bottle, resulting in carbon and crud build up on the butterfly in the inside of the throttlebody

and 3) oil then contaminates the throttle position sensor causing it to malfunction and read the incorrect position.

NOW, if oil is on your MAF sensor, it cannot get a correct reading of the amount of air travelling through the system. In a fuel injected car, when you step on the gas, you are actually stepping on the "air". All it does is open the throttle body wider allowing more air to come in, unlike old carbeurated engines which put more fuel in. The MAF "sees" this the computer then puts more fuel in to the air mixture based on a predetermined chart and the position of the throttle body (which, oh by the way comes from the the throttle position sensor!).

Now, even if you have cleaned the throttle body and the MAF, if you did not clean the entire air passage (take it off the car and clean it with a good degreaser or throttle body cleaner, let dry and then reinstall), everytime you start the car and use it again, the excess oil that is still in the air intake passage will eventually get back all over everything

especially if you continue to over oil your performance air filter.

'nuff said

Bryan

Pearlpower

iTrader: (2)

94k miles and no rough idle.
All service performed by myself even before scheduled.
New TPS installed
Throttle Body cleaned.
Idle is butter smooth.

Awesome car. So yes, I still would of bought the GS over a BMW, Benz, Audi ,and all others because-NO ROUGH IDLE.

tinygs

Good suggestion.....makes sense to me. I havent had the TPS inspected/changed, that might be something to consider. I do clean the SRT intake filter periodically, but dont have enough miles on it to necessitate a wet wash and re-oil.... I hate to even ask about it on this thread because its been beat to death, but is the TPS something that is routine to completely replace? Also, is it an item that I could replace myself as a preventative maintenance??? Ill do a search for that as well..... Thanks, Tiny