gio89kid

I have a 2007 chevy HHR 2.4L 142000 miles, automatic, which recently had a p0011 code in the computer but not on the dash, and a traction light that was on the dash because of this. So I changed both VVT valves and that fixed it.

Now, here is what happens, every morning I start the car and it starts up perfectly and then 1.5 seconds later you here a small thud almost like its going in gear but its still in park. I then put it in drive and no problems.

Driving throughout the day is normal transmission feels good, give it gas and it down shifts and there is nice power. Cruising around is perfect, sometimes you can feel it shift gears but never a thud, like the transmission is breaking or anything.

I had the transmission filter changed along with the fluid when I purchased the car at 115000 miles and again at 140000 miles. The first time the transmission shop said it had never been changed before but felt the transmission was in good shape, that's when we had it checked out before we bought it. Now the second time, the guy said everything looked great, and both times I payed a little more for the additive they recommended.

ANOTHER QUESTION I have been wanting an answer to is...
on all my other cars that I have had in the past the rpms stay pretty low on the dial not usually going close to redline even when racing it up a hill, but this one will go into the red line before it shifts when racing it up a long hill. Is that normal for this car!!! I noticed on the dyno charts that I have seen for hhrs it usually goes to 6500 rpms, I don't want to mess up the car, if I see it going that high I usually back off the throttle, but if not it shifts at redline and does not whine, just brahhhhhhhhh, shift bruhhhh, whisper. lol and the temp of the car on the dic stays in the perfect range.

Mind you, I don't drive like a crazy person, I live up a long freeway hill and it happens sometimes "RARE". Car has been well maintained, semi-synthetic oil changes, and fresh coolant change, fresh brake fluid flush, no oil leaks, its the best maintained car ever.

when turning on the air-conditioner in the past it did make the rpms surge up and down until it leveled off, but that seemed to go away after the VVT valves were changed, but i guess it could be the compressor clutch that gets stuck for a second at start up each morning, but this happens the the AC on or off, so I don't know.

Oldblue

Next trans fluid and filter change forget the additive.
The clunk could be many things from torque converter to timing chain tensioner, perhaps a video posted would help pin point it.
As for the hills and the redline mine also has done this since I purchased it in Dec 2009

gio89kid

Thanks old blue, your always helping me out, I will see if I can get a video.

gio89kid

Ok, now I could use some help.
I made a video of the noise, you can clearly hear it in the video.
I also found out that i can recreate the noise, when ever i move the transmission from reverse to drive or drive to reverse, but its much less noticable.
Drive to I to L have no noise at all, only when going from R to D or D to R. Neutral and Park are fine too.
Here is a link to the video.
Ignore the muffler video.

Oldblue

I tried but that video wouldn't open on my IPhone, give me a day and I'll try to open it on my laptop! It's been a hectic couple weeks and I forgot to charge it up!

843de

Your video opened up for me, and the noise sounds like a sticking shift solenoid, I'll give it another listen when I'm back in NC tonight on the desktop computer with the big speakers....not the rinky dink speakers in this i-Pad.

Then I can really crank it up and see if it still sounds like a solenoid hanging up.

And to second Oldblue, transmission additives are usually bad news, I've seen them kill a transmission in a few thousand miles.

Oldblue

OK , I got the old laptop out!
I listened closely and have a few suggestions
first, double check your trans fluid level. If it is low and you have to top it up then do that and test for the clunk, if its gone then great, if not, then ....
second disconnect the neg cable at the battery, to avoid any possibility of a short and fried computors, check the ground cables at the stud on the transmission case by the oil filter housing.
check the shifter cable adjustment anything loose? if so tighten it up.
check the connection to the TCM, any loose or bent pins? any dirt in there?
now reconnect the neg cable at the battery.
test time does it still clunk? no, great the inexpensive things fixed the problem!
Yes it is still clunking , well then time to replace that shift solenoid 843de mentioned


GM's 4T45E Transmissions: The Good, Bad And The Ugly


I hope this helps, I'm not saying this will fix the problem but this is how I would diagnose the clunk!!

gio89kid

Ok, I'm on it.
But, if worse comes to worse...
What am I looking at?
I mean the transmission still runs good through each gear, no clunking or anything, maybe a little hesitation sometimes, but still good.

Oldblue

Run it till it drops! Or stops! Meanwhile hunt down a used or new transmission.
Or it could run till you sell or trade in the HHR