Check Enigine Came On - Car Won't Shift Out Of 3rd

mwbuck · January 6, 2004

Hi all,

I have a 2000 RX with 35,000 miles on it. Until today, I have not had one problem with the car. It drives like a dream and I treat it like gold. While I was driving to work today, about 3 minutes after pulling out of the driveway I heard something in the engine. It sounded like an object fell completely through the enigine bay. At first I though maybe it was a branch or something in the road but when I looked in the rearview there was nothing. As soon as I brought my eyes back on the road I noticed the check engine light came on. The car seemed to be functioning normally so I was not that worried. Then, 2 minutes later when I got on the highway, I noticed the car would not shift out of 3rd gear. Driving at 55mph the tach reads 4000 rpm (which is about higher then I've ever pushed it). I pulled the car over on the highway and turned it off, checked out the engine bay and didnt notice anything. I turned the car back on and the problem remained. Shifting is normal 1st through 3rd gear but it just will not shift out of 3rd. Anyone have any ideas as to what the problem could be??? I already have an appointment at the dealership for Thursday for an oil change but I'm not sure if I should take it in today and see if they can take a look at it. I drive 60 miles a day on the highway and I don't want to make the problem worse. What do you guys think I should do???

tmastres · January 6, 2004

Allright I'l bite first here, I have no idea what could have fallen off our out to cause this problem but if your dealers with in 10 or so miles I'd drive the car there immediately. They shoud give you a loaner so you wont be out a vehicle and I'd bet good money they'll know exactly what happened. With so few miles you should still be under warranty so why bother with anything else. Just MHO.

mwbuck · January 6, 2004

Yeah thats what I'm going to do. I drove the car into the city after this happened which is a total of 15 miles. I'm driving it to the dealer at lunch today which will be another 15 miles. The car is under warranty until July '04 so hopefully they'll be able to take the car right away and I hope they won't hassle me about wanting a loaner on such short notice.

lexus01 · January 7, 2004

Running your car at 4000 rpms in third gear is not going to hurt your engine; but it is going to hurt your gas mileage.

The dealer is going to read your car's on board diagnostic codes (OBDII) to troubleshoot the problem. Ask him what the code(s) value is and let us know here.

I had a similar problem with my car not shifting into fourth and it turned out to be a failed Mass Air Flow (MAF) sensor. The OBDII system recorded a P0171 (System Too Lean) error code. The problem turned out to be a defective MAF. The MAF was letting in too much air causing the lean condition. The lean condition was causing engine knock that I could hear.

The knock sensor also failed triggering code P0330; the knock sensor must have been working overtime counteracting engine knock caused by the lean condition.

As you can see, one sensor failing can generate additional failures as in a chain reaction.

By the way, the Lexus transmission only shifts into first (D) mechanically. All other gears are shifted electronically or via the computer.

Can you hear any engine knock?

mwbuck · January 7, 2004

thanks for the informative reply lexus01, I hear no engine knock. The only sound I heard was right before this started when it sounded like something fell through the engine bay. I just thought it was a branch or something I ran over but immediatley after I heard it, the check engine light came on. I dropped the car off today and I hope to hear something from the dealer tomorrow. I will find out the error codes and post them.

One thing I found reassuring was when I was at the dealer, the rep told me that the previous owners of the car brought it in for every scheduled maintenance up until I bought the car. I've put 10k on the car since then and I treat it like gold; so it was good to hear that the previous owners seemed to have cared about the car as much as I do.

mwbuck · January 7, 2004

Well, here's the deal. The dealer called me this morning and said that apparently, a wireharness connected to the transmission had been chewed apart by an animal. He said most likely it was a squirrel looking for a warm place to spend the night. I am very intruiged by this explanation as it seems quite extrordinary that this problem is the result of a squirrel. Either way, I asked the guy to make sure the technician saves the chewed up harness so I can take a look at it. Labor is $99.50/hr for 2.5 hours so I'm looking at a $250 bill. Hopefully when I pick it up later today the car will resume working as it did before.