dbarber45

Ok, Members. I hope this hasn't been answered before. I failed to find any threads after doing a search. I have a RX300 first generation with 85,000 miles. Lately it has been dying on me in the driveway now that cold weather has set in. Is there a member who could recommend what the issue might be? Auto choke problem? Air/Fuel sensor? I'm just trying to get a sense of what the problem might be before I take it to my dealership and spend big bucks for them to do a diagnosis.

FastTags

Perhaps one if the fuel lines is freezing up. Maybe poor starter.

kalali

Is the check engine light on?

salimshah

Please read the having problems start here sticky.

Salim

dbarber45

Sorry, but I am unable to find the "sticky" you reference. However, let me add that I just a few months ago removed the Air Idle Control Valve and did a thorough cleaning. So I think I can rule out the IACV. Now, I have read in other forums that the Mass Air Flow Meter could also be where the problem lies. If you want me to read the sticky still, please put a link to it as I can't locate it.

salimshah

https://www.clublexus.com/forums/rx-...a-problem.html

A solid blue line separates the sticky (persistent) threads from new threads.

You can not rule out a broken IACV.

Salim

dbarber45

Thank you for the link. I read the Start Here posts. I guess in my case the post that comes closest to what I'm experiencing in cold weather is IACV problem. This only occurs when the outside air is below 40 degrees. Sometimes it is necessary to depress the gas pedal all the way to the floor for the engine to start. Then the engine may die if you let your foot off the gas too quickly. Once the engine reaches operating temperature it is fine. So it's difficult to start in cold weather and will occasionally die when you place it in gear to backup. So it seems I may indeed have a problem with the IACV if this could cause poor starts in cold weather. BTW if you replace this part, do you customarily have to reuse the old mount screws from the original part? Like everyone else that has tried to remove this part, I'm sure I could use some new mounting screws that still have a good head on them.

hypervish

First start with cleaning the IACV, no need to replace it. You will find a DIY here.

dbarber45

Thank you for the suggestion, Hypervish. I actually did perform a cleaning of the IACV about 3 months ago. Was not having any problems at the time. Just thought it might be a trouble spot later on. I have only had the car around 7-8 months and it had been sitting on a sales lot for about a year before my purchase. So I'm wondering if that could still be the problem. From an earlier post by Salimshah these parts can apparently go bad...but there are hardly any moving parts in the thing so I'm not sure what could break or not operate properly. I could replace it I guess but not convinced that is where the problem lies. We have warmed up where I live so for the present I have not had any more problems. Will have to wait for another cold spell to evaluate things further.

hypervish

Ahh, sorry. I was in a rush this morning, and didn't read the previous posts. Hadn't realized you already cleaned the IACV.

salimshah

Hyper's question is still valid ,,, the slug should spin freely 90 degrees. This allows the electromagnet to control its position.

When the IACV is replaced, the coil and and the slug are replaced together.

Salim

dbarber45

Thanks to everyone for the feedback. I will focus on the IACV first.

dbarber45

I reread all of the Do-it-yourself posts on cleaning the IACV last night and prepared myself to do this today. Took the easy way out and drove to my garage since the wind chill was about 25 degrees this morning. The slug (piston) , or whatever the rotating part is known as, was definitely NOT rotating freely. Mechanic said he couldn't understand why I didn't have a "check engine" light on somewhere. Anyway, sprayed liberal amounts of throttle body cleaner into IACV and onto butterfly valves. Since tomorrow morning is set to be about as cold as today, I should know then if this has corrected the problem. Worse case scenario, I guess, is to replace the part.

salimshah

Fail to hold idle is not a condition to set CEL.

So is the slug moving freely after the cleanup.

Salim

dbarber45

So are you implying that this may only be a temporary fix or not really a fix at all? I'm not sure what meaning to give your terse response. If you are implying that the part could still be faulty, I'd be obliged if you would just say so directly. If I experience the same difficult starts tomorrow do you recommend replacing the IACV ? As perhaps the problem is in the coil unit ?