I have an 03, 5AT sedan with 161,000 miles on it. Some time last week, I noticed a weird sound when I'd get on it. I was in traffic, so I wasn't looking at the tach when it happened, but it sounded like it was hitting the rev limiter and coming down a little before going back up to that same point a few times and then shifting. Well, I was able to duplicate it when I could watch the tach, and it'll actually rev, lull a little, and then continue to rev higher. This happens a few times before it shifts, like it's not sure which gear it wants to be in. Whether it wants to shift, or continue to rev. It does eventually shift, and the noise goes away. I'm not even sure which gear it happens in. It just happens when I get on it when I'm getting on the freeway. I try to duplicate it, but I must be in the wrong gear every time I try. And SoCal traffic keeps me from going through all of my gears whenever I want to.

I've tried searching, and all I can find about problems with this transmission is that they don't have any problems. So I'm hoping that someone out there will know what's up, and what I need to do. If I need a complete rebuild, should I do that? Should I look at a salvage yard for a used tranny? New? Should I buy a different one? Will a G37 tranny fit? Any opinions are appreciated.

 

have you ever did transmission flush? possibly low on the fluid? smell anything burnt from engine bay?

 

I've been told that it's not a good idea to flush a transmission with that many miles on it. I'm not sure what any of the three previous owners did to it. I was planning on changing out the fluid this weekend, but then this problem came up. I don't smell anything burning at all. The only symptom is the way it's revving.

 

I had exactly what you are describing on my 6mt when I first got it. I went through hell finding out what the issue was. Turned out that the wiring harness was not fully connected believe it or not. Just secured it plugging in and Magic!

 

I'll check that out. Thanks!

 

Yeah I hope you do. I thought it HAD to be mechanical...but nope! It was absolutely 100% electrical. Its been a year and a half now problem free. I had thought that my engine was messed up or something. I was like "why am I hitting a rev limiter at 5000rpms?"

 

Well, I had a diagnostic run on the tranny, and everything looks good from the outside. I forgot to mention that I have a high idle RMP CEL, as well as a steering/cruise control switch CEL. My friend/mechanic is saying that this could be the problem. Does that make sense to anyone? I know that everything is all connected through the PCM. Maybe the steering switch makes the car think that I'm too hard in a corner and it's trying to take power away from the wheels?

 

Did you check over ALL wires and wiring harness?

 

I didn't personally check anything. I took it to a transmission shop and they did a free diagnostic check for me. So I'm assuming they checked all of that stuff out.

Is it normal for a plenum spacer to throw a high idle RMP code? It makes sense, since there's less pressure in the intake manifold, so the engine has to rev higher to compensate. Could that cause this problem? I really don't wanna take the spacer off to see if that's the problem.