Hi folks!
It is sort of mystery to me...
I have 2002 ES300 with 171K miles on it.
It is developing some issues that puzzling my dealer almost all the time.
Recently after a car wash at the dealership (I have 130 free car washes at Kuni) when I am backing up from parking lot it starting to run rough when I put it in reverse. Slight tapping accelerator would cure that roughness.
Dealer also replaced vacuum hoses recently due to check engine light.
Also noticed after putting a full tank of gas computer showing that I have 247 miles range, compare to a three years ago when it showed 320 miles.
I have new one on order coming in May and wondering if my car will last until new will arrive.
I am at the point that any repair will cost more that a car.
Am I safe to drive it until May?

 

My fuel range was always in the mid 250's but I could always get much further. It's just an estimate and better to be conservative than overly optimistic.

Winter fuel economy is always worse than summer, the fuel blend is adjusted for the cold and it takes longer for the cars to get up to operating temp.


As for running rough at idle, it could be the throttle body , IAC (idle air control) valve needs a good cleaning.

 

A few things it could be:

Worn spark plugs
Air leak
Could be a bad motor/transmission mount (not sure precisely what "rough running" is, but it could fit that description).

I doubt the fix is actually expensive part-wise, just a matter diagnosing it. Which, if you can't do it yourself, can indeed get pricey. Unless you have damaged the body or interior badly, the value of the vehicle should still be much more than any small repair.

 

Does the problem always occur after a car-wash? It could be water seeping its way into the intake. I'd also get the throttle body cleaned and any check engine codes scanned.

 

Thaks guys for the ideas.
Usually I am servicing and fixing my car at Kuni Lexus.
In December I has vacuum hoses replaced and earlier last year - ecv valve done.
Yesterday I stopped by and have car checked. They pulled some codes related to cylinder 2 but not current.
Since problem occurs after car wash, they afraid this because windshield sealant is leaking right on wiring harness.

 

Take a spray bottle, fill with water, and with engine running spray all around the suspected area. See if engine hesitates.

Don't spray directly on any electronic components, but spraying on wiring is fine.

Phil

 

Thanks for the tip!
Tonight I will have an excellent opportunity - we are expecting some rain in Denver.
If I get the issue come back, I will reseal the windshield.

 

+1 Vacuum Leak, Check the hoses, especially the one that goes to the to of the Throttle body, allot of heat there and it tends to harden the rubber and crack it.

When the rough idle occurs, spray some ether aka start fluid around the hose. If idle goes up then you will have a general idea where the leak is.

Take care the ether is very volatile

 

Vacuum hoses been replaced a couple of months ago.
After snow melted didn't get rough idle.
Mu only guess is that water going where it shouldn't be going only when sprayed under pressure.

In any case I am getting a little more comfortable estimating that my car will run until May when my new arrives