cwest

I have its 1999 ES300. with appx 103,000 miles.

Vehicle was dealer maintained until 90k service.

However, 99k car was dieseling so bad after keys off the ignition or starting.
with "Check Engine" and "TRAC OFF" lights on instrument dashboard.

so i brought it to dealer and they said i had bad main catalytic converter so I replaced it ($1000) they said the whole maniford. oh and LEXUS WARRANTY only cover our cats until 80k miles.

NOw after one month, car is acting the same way it did.

I'm assuming it has to do something with cooling systems?

I didn't see any fluids leaking, but I could visually see my coolants were low.

Symptoms are:
1. After 12 hours, without running the car. Vehicle Starts rough, not idling just feels rough, Rpm kicks in like its chocking the engine. then exactly, 2minutes after, i could feel huge amount of heat coming out of engine bay.

2. Exactly driving 20mins or so, parked up-hill. let it run lil while, then shutting it off? Car failed to shut off. engine was still alive!!! I mean it was alive half way.(Dieseling I guess) with sounds like a zoo. Choking Choking.
so i waited long about 4min then finally animals left my engine bay.
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I took it to a local mechanic, and they said nothing is wrong with the vehicle.
This car runs fine, but troubles when starting and shutting off. oh yeah and no check engine lights from instrument dash.
Plz, Help me out guys.

Lexmex

Is it like a tapping noise coming from underneath the vehicle? What about your oil levels and the last time you changed it out.

cwest

i could describe it as tapping noise too. but engine oil levels are fine.

cwest

Maybe this is about "BLOWN HEAD GASKETS"???
Cause, i just checked my coolants it was dirty lil black stuff swimming
around in there
Maybe i need a compression test?

Lexmex

There is probably a leak somewhere, but a mechanic would have to see this firsthand and dig a little deeper to check it out. I would definitely have them pull off the valve cover, too, which is something I don't think Lexus did.

mitsuguy

iTrader: (2)

carbon deposits inside the cylinders???

at this point anything is going to be far fetched, but it falls into the category of symptoms...

shouldn't be too hard to pull the plugs and peek down inside with a flashlight...

a "block test" would be invaluable as well - this is when they test coolant for hydrocarbons effectively showing a leaky head gasket, it's also only $20 at most shops, and takes 5 minutes to perform once the car is cool...

spark plugs themselves are another potential culprit, a quick inspection of them will reveal anything that can be causing a problem (although while in there, might as well replace them)...

on a similar note, where do you get gas? for the main cat to become completely clogged with only 100k miles on the car, it usually shows incomplete fuel burn and that leaves bad carbon deposits as well in the cylinders... might be time to start using higher quality fuel (not octane, just from a better gas station, possibly)

VVT-i

When your cat converter gone bad the first time its may came apart and left some of the small piece inside the rest of the exhaust system. Also,check the cam timing. It's sound like mechanical problem than electrical. Just me .02 cent.