Jeff92se

ie.. will be attempting to reverse or will be idling at a light and it will stumble and turn off. Common problem?? No check ingine light. Air filter is fairly new. OEM plugs but not due until 90k? We have about 60k right now.

Only problem I had before was the maf sensor check engine code. Which I fixed by gently cleaning the oil gunk off of it and resetting the code.

sczc400

You need to clean your IAC on the throttle body closest to the firewall, that will fix it if there is no check engine lights. Unless there is some other information you haven't mentioned.

bizzy928

We had the same problem. At an idle the engine would stutter and stall. No problems restarting it.
First we replaced the battery. The problem disappeared for a few months. Then we got an CEL and the dealer replaced an O2 sensor. The problem has not reoccured (~1 month later).

I don't know if it was the battery and/or the dying 02 sensor... But the problem seems to be gone now.

Jeff92se

Well I finally drive the wife's RX yesterday. Starts fine of course. But blipping the throttle resulted in a slight hesitation in park/neutral. So I took out the maf sensor. It was just slightly coated with oily/dirt. Not nearly as bad as the 1st time. But since it takes all of 5 min to do......... Reinstalled it and then took it for a drive. Hesitation went away but won't know if it fixed the problem permanently or not until I hear back from the wife later today.

HarrierAWD

By any chance, do you use K&N air filter?

Jeff92se

Nope. But I'm very familar with K&N's cone and panel filters. I never had a problem with either on my maximas. But it does require some common sense when cleaning/reoiling. The lack of being the primary source of problems regarding oily mafs.

Jeff92se

Okay after about a week or so, the problem as not come back. So it's fairly safe to assume that the maf sensor was to blame. I don't know why it's getting that oily coating. But the engine compartment is getting dusty/oily. I should do an engine clean on this thing.

Depending on where the stock airbox is drawing air from, maybe it's the dirty engine compartment. It's actually fairly clean. But due to the crappy way Toyota locates their oil filter, it's almost impossible to remove the filter w/o making an oily mess on the engine block etc.... stupid.

HarrierAWD

My mechanic always used a rag to clean the engine mount after removing the oil filter. Toyota & Lexus techs do the same. Agree with you that it is a rather retarded design for the RX300 or the 1MZ-FE engine. I would do my own oil change if the oil filter were located underneath the vehicle where I can easily reach. That'd save me $20 each time.

Jeff92se

CRAP! Wife says it died twice today. I guess I'll try cleaning out the iacv. I've been looking for a Lexus service manual. Anyplace besides Lexus (rape-ola price) that I can get it from? Ebay was nada so far. Thanks

The other idea is to get a service manual for the same year camry. Should work for the engine applications. Of course everything else is diff.

Found some real good info here:
Description:
http://us.lexusownersclub.com/forums...=17360&hl=iacv

Pic of location:
http://us.lexusownersclub.com/forums...c=7408&hl=iacv

Jeff92se

I'm going to try cleaning it tonight. Looks simple enough. Will advise.

xravexboix

Make sure you also clean the throttle body.... carbon build up in the t-body contributes to the IAC valve sticking. It seems to be a fairly common maintenance replacement on the RX 300 models... Cleaning it will help solve the problem for now... but you may end up having to replace it within a year (lots of time)

Jeff92se

Not sure what that has to do with the idle. with both thottle plates closed, the air travels down the hole in the right TB and down into the iacv. I took that black thing off and it was perfectly clean. Here is the pic from the other thread: If you take that thing off, there is nothing that would allow gunk into it. BUT if you look at what that black thing is attached to, THAT thing handles the air when the TB is closed. There is a hose below it that leads into the head area. I sprayed cleaner in the right TB and it came out the bottom where that hose connects to. It did have some oily gunk but it was basicly pretty clean. Nothing I would think would cause and idle problem. So although the wife said the car drove okay, I don't know if this will fix it or not.

JZA80MHU38

Is there a EGR Valve on this engine? My friend had a Camry which has a similar problem before. Seems like after he travelled at higher speed and then slow down, the problem will appear. It didn't happen in slow speed-alone travelling -- like driving just for one block. Turned out the EGR valve gets sticky and didn't flip back to the normal position, causing the exhaust gas to route back to the engine even at idling speed (hence the engine stall).

I don't know how accurate it is, but that's what the mechanic told us last time (after multiple diagnosis by several other shops, and their fixes didn't really fix the problem), and after he changed the EGR valve, the car runs great (he had about 120K miles on this Camry though).

StrmRdr23

i had this exact same issue the other day...i drive a 2000 rx with just about 90k on there...doesn't appear to be an electrical issue...lemme know what you find out...i had the throttle body cleaned as well as the fuel injectors last time i had my oil change done...that was about 2 months ago...i can't figure it out...

StrmRdr23

hmmm, i noticed that as well...i just got off the freeway and stopped at the light...i had about 1/4 tank of gas left, and i was facing downhill...i always fill up with supreme at the shell station so i don't think it's shiesty gasoline...one of my friends thought it might have been air that got into my fuel lines? i know it's fuel injected and what not but it seemed to make sense at the time...*shrug*