My 2007 with the 2.4 engine and the automatic started intermittently shifting abruptly when it is going through the gears and if I were to shift into drive while rolling back a bit , I am sure that's a no no but i've never had a transmission seem to mind, it really clunks into gear. This has been going on for about a month not all the time but my wife is the primary driver and doesn't notice it. The car has 86K and we've not had any problems with it aside from the crap brake rotors it came with but slotted ones fixed that. The only other problem we have is a son who is very hard on anything he drives. He just cannot get it through his head that he's not on a race course. Any ideas?

 

A) no CEL?
B) maybe overheating, that will cause hard shifting, check coolant level under the pressure cap.
C) slotted rotors did not fix anything, the brake job did along with adjusting the rears manually. They may make it look cool, but do not cool the metal and in fact, there is less metal to absorb the heat not more area to dissipate the heat.
D) get rid of the son, or give him a disposable 1990 toyota.

 

You beat me to it with your suggestion in "D".

 

With 86k on the clock, servicing the transmission probably wouldn't hurt.

Option "D" may be tempting, but he may be the root cause of the transmission's recalitrant behavior. Hydramatics are very durable, but throw in an over exhuberant teen driver and probably a fair number of "neutral drops", it's saying HELP ME!

 

Also check oil level, and do a oil/filter change if it is overdue. Low, or dirty oil messes with the camshaft actuator solenoids that does the variable valve timing - if they get contaminated or run without an adequate supply of oil, the trans will start shifting rough, and sometimes lights up the Check engine light.

If the CEL is lit, get the codes downloaded and post them here - we can likely give you further suggestions.

 

Actually the CEL come on and goes away every once in a while and yesterday it was on when it was shifting rough and last night I noticed that after I had gotten gas the CEL was off and it was shifting normally. It's going in for an oil change tomorrow. If the CEL is not on will the past times it was on show codes?

 

As far as I know the codes are stored so they can scan and pick them up.. I had a similar issue on my Tracker, it was a bad speed sensor , also the contacts on the sensor get corroded.. FYI:I don't know if the HHR has a Speed sensor on the tranny! as mentioned if the tranny oil hasn't been changed in 50/60 k do it while in the shop.
But as mentioned I would first check the tranny oil level........
Please post what you find! Good luck

 

and it could be those pesky Camshaft Actuator Solenoids themselves.

 

Are those like the older speed sensor's? Im no gear head so Thanks for any info....inquiring minds want to know :)

 

Nope, they are part of the Variable Valve Timing mechanism. Do a search for SOLENOIDS here, and you will find a lot of info on them. A fair number of people have had them go bad, needing replacement.