hitthepin

Alright...my RX would not stay running this morning. I can get it to turn over after a few tries if I gave it a good amount of gas, but the second I take my foot of the gas, it just spudders and dies.

A couple of years back at around 55K miles, I had a similar problem. Sometimes it took 7 or 8 tries for the car to turnover, but when it did, it would stay on. I cleaned the IACV and the problem went away.

Now with 79K miles, the car is having similar problems, but this time it won't take me many starts(with gas) to get it going, but it'll automatically just turn off.

So before I start taking apart the IACV to clean it, any other ideas on what it might be? Could it be the fuel line/injectors? Should I clean the MAF? From what I can tell no check engine light so I'm assuming no codes got thrown. Something else...maybe muffler.

I did just recently change the battery last week and everything was working fine up till today. I put in an Optima Red top; Group 35; Cold Crank Amps 720; Crank Amps 910; Reserve Capacity 90.

Open to all suggestions, thanks as always.

Lexmex

I'd also take a look at the air filter, especially during hot summer months. Also check to see that all hoses are properly connected, namely the one by the PCV, and have no leaks or cracks.

hitthepin

Thanks Lexmex. I know its not the air filter cause I just changed it only a 300 miles go when I did my last oil change.

I'll check the PCV though. Good suggestion there.

Lexmex

The IACV can get that dirty even after a few years. I frequently clean mine and sometimes even have take off the bolts in lieu of spraying through the hole.

DriftGirl

iTrader: (6)

pull codes.

Should also check Fuel ECU.... I was having the same problem with one of my cars. I suspected the iacv and adjusted/cleaned it. It worked a little better but the problem came back. Finally checked my fuel ecu (swapped it with anther car I have) and now it runs PERFECT.

G' luck!

hitthepin

I'm pretty sure it didn't throw any codes. No check engine light or any other instrument lights.

Maybe I should pull the ECU just to reset everything?

carguy07

See if you can get it started and keep it running with the throttle cracked open. If it is the IAC it will still run just fine with at 1/8-1/4 throttle.

I would be very suspicious of a battery problem since you just swapped it and the fact that it is an Optima. They used to make a bulletproof product several years ago, but Johnson Controls bought them out a while back and now the quality control is terrible. An old one will last forever, but a new one .

hitthepin

Thats exactly what I did the last time I cleaned it. I took the entire valve off and cleaned it. Q-tipped the insided after spraying it with cleaner.

Got a question though. Is it ok to spray the cleaning directly into the throttle body?

hitthepin

I can keep the engine going if I give it gas..say keep the RPM's at 1000+ or so. Its just the second I let my foot off the gas, it'll just die out.

Yeah, I didn't think it was the battery either, but I figured I'd mention it since I just changed it. Not sure if funny things happen when installing a new battery, but never know if I tripped up something during install. 99.99999% positive I didn't though.

Lexmex

What I am referring to is spraying in this hole. I sometimes spray into the the two sides of the throttle body itself...and most often get some white smoke out the tailpipe as a result, but the issue, if it is a low RPM and air intake related revolves usually round the IACV being dirty and causing the IACV valve to stay mostly closed causing too low an RPM and the vehicle to die. Sometimes I can get away with spraying in here and sometimes I actually need to take the two screws off and turn the valve.

hitthepin

Lex, thanks for the pic. I'm familliar with the IACV cleaning as this was my second time cleaning this. My question was whether I should, or is it safe to open the butterfly flaps and spray some cleaner directly into the throttle body itself.

Anyway, I just got done with this job. I didn't spray the cleaner into the throttle body, but I did clean the butterfly flaps and the IACV. The RX is running perfect now.

While I was doing that, I also pulled the PCV. Mine is not the black plastic elbow, its a metal one with a thin 3/4" hex bolt on the bottom. I pulled it off and cleaned that as well. Not sure if its an indication of sludge, but the bottom of the PCV valve had brown/rusty colored gunk on it. Looked like a thin layer of dried chocolate frosting.

There's a piece inside the PCV valve that moves up and down(should rattle). It appeared to be stuck until I cleaned it. Now its moving up and down freely.

Also adjusted the throttle cable per your(lexmex) pass instructions moving the 10mm bolts all the way left.

Just came back from a test drive and its running well now. Thanks again to all the members here. I love this place.

Lexmex

As far as spraying through the throttle body...you can do that, BUT I usually don't recommend doing too much. I have done usually about 15 seconds worth on each hole, but one time I must have done about a minute with some carb cleaner and ended up killing an ignition coil. The day after was when I sanded down that Camry ignition coil that I had to use until I could get one for the RX down.

hitthepin

Good to know. The next time I'm in there I'll only do a quick spray with the flaps open. What I did this time was spray a bunch of cleaner on a rag, opened the flaps and wiped them clean. Didn't want to take any chances spraying directly into the throttle body when I wasn't sure if it was ok.

Again, I love this site!!! If this were to happen to me in the past, I would have stressed out having to tow the car to the dealer or mechanic and not having the car...etc. Instead I got right in there and had it fixed in a hour or so while my kids took napped.

lexus114

Hytthepin originally wrote:
Also adjusted the throttle cable per your(lexmex) pass instructions moving the 10mm bolts all the way left.

Lex,what is the reason for doing this again? Does it make the throttle more responsive?

Lexmex

Yes, it tightens the accelerator cord.