Mowdy

My 2006 HHR 2.2L has 84000 miles on it and started shifting hard from 1st to 2nd and a little hard from 2nd to 3rd. If you shut the car off and let it sit and then drive it, it typically goes away.
The transmission hasn't been serviced yet so my mechanic is going to check for any hidden codes (no cel as of yet), drain the tranny and put in a new filter kit with some Lucas additive.
Has anyone else had this happen? Any other suggestions? The engine runs great no matter what.

donbrew

Try the search tool, you are far from the first. More like the 300,000,001st.

overheating sound likely, but not always.

whopper

It is very likely no fault of the transmission - when the computer detects something is going wrong, under certain circumstances it will start shifting firmly like what you are experiencing, and eventually light up the Check Engine Light (CEL). Once the CEL lights up you then need to download the error code. the error code will help point in the direction of the problem.

At this point I'd suggest you save your money on the transmission service, and cancel it.

Lucas additive? save your money - it is not needed, and is likely not approved by GM for the transmission.

Mowdy

Thanks for the info, I ran my code scanner and it came up w P1818 but the cel is still not on. I heard that this code can set if it senses you rolling in neutral when going into reverse and so on. Is this accurate? I also read that the Tcm may need a reprogramming. Thanks again!

donbrew

You will need somebody with a TechII scanner and access to TISWEB, I.E. a GM service department.


#07-07-30-005C: 4T45 Transmission, MIL/SES On,
DTC P1818, Power Door Locks, Cruise Control, Shift
Interlock or Retractable Hardtop Inoperative, Engine
Speed Revs Limited, Hybrids-Autostop Regen or
Boost Inoperative - (Apr 8, 2009)
This bulletin is being revised
to add the 2006 model year
for Cobalt, Pursuit, G6, and
HHR. Please discard Corporate Bulletin Number 07-07-30-005B (Section 07-
Transmission/Transaxle).
Condition
Some customers may comment on the illumination
of the Malfunction Indicator Lamp (MIL) or
the Service Engine Soon (SES) light, the power
door locks, cruise control, shift interlock,
retractable hardtop being inoperative and engine
speed revs limited to 4,000 RPM in first gear
after a cold start or cold soak with temper
atures between 0° to
10°C (32°F to 50°F).
Customers with hybrid vehicles may also
comment on the following conditions:
-- Hybrid Autostop, rege
n or boost inoperative
Cause
These conditions may be caused by the TCM setting a false DTC P1818 (Transmission Fluid
Pressure (TFP) Valve Posi
tion Switch Indicates Drive without Drive Ratio).
Correction
Verify the conditions and repr
ogram the transmission contro
l module (TCM) with the new
updated calibration using the procedure below.
1. Check for DTCs.
2. Clear DTC P1818.
Subject: 4T45 Transmission, MIL/SES On, DTC P1818, Power Door
Locks, Cruise Control, Shif
t Interlock or Retractable
Hardtop Inoperative, Engine Speed Revs Limited, Hybrids-
Autostop, Regen or Boost In
operative (Reprogram TCM)
Models: 2006-2007 Ch
evrolet Cobalt, HHR
2007 Chevrolet Malibu
2006 Pontiac Pursuit (Canada)
2006-2007 Pontiac G6
2007 Pontiac G5
2007 Saturn AURA, ION, VUE, VUE Hybrid
with 4T45 Automatic Tran
smission (RPOs MN5, ME7)
3. Start the engine.
4. Apply the brake pedal.
5. Place the transmission in reverse.
6. With a Tech 2®, monitor the transmission
fluid pressure (TFP) switch parameter.
Important:
Confirm the newest calibration includes the "false P1818 fix".
An updated TCM calibration is now available to
address this concern. This calibration, or any
that follow, is designed to address this conc
ern. Reprogram the TCM with the software now
available in the TIS2WEB using the
Service Programming System (SPS).
If you cannot access the calibration, call the
Techline Customer Support
Center at 1-800-828-
6860 (English) or 1-800-503-3222 (French) and it will be provided. As always, make sure your
Tech 2® Diagnostic Scan Tool is upda
ted with the latest software version.
Clear any codes and verify th
e condition has been fixed.
Warranty Information
For vehicles repaired under warranty, use:
•
If the TFP parameter indicates Reverse,
reprogram the TCM with the updated
calibration.
•
If the TFP parameter indicates Park/Neutr
al, refer to DTC P1818 in SI for further
diagnosis.
Labor
Operation
Description
Labor Time
K5364
Transmission Control Module Transmission
Reprogramming with SPS
Use Published Labor
Operation Time
GM bulletins are intended for use by professional technicians,
NOT a "do-it-yourselfer". They are written to inform these tech
nicians of conditions that
may occur on some vehicles, or to provide in
formation that could assist in the proper
service of a vehicle. Properly trained t
echnicians have the
equipment, tools, safety instructions, and know-how to do a job
properly and safely. If a condition is described, DO NOT assum
e that the bulletin
applies to your vehicle, or that
your vehicle will have that condition. See yo
ur GM dealer for information on whether your veh
icle may benefit fr

M DC

the tcm has to be read w a tech 2 tool or tranny code reader
find a tranny place that can read codes for you and see if anything pops up

hurst2001

Well just throwing this out there ,i had the same problem shifting hard after i change the air filter and were the rubber hose in front that runs down off the air box is a clamp to tighten to the manifold ..Well as what i understand with it being loose and let more air in then if it was tight and the computer was trying to adjust and threw the shifting off and started shifting hard ..After i tighten it up the hose clamp no more problems and shifts smooth .. I do not know if this apply to your problem..

whopper

Good tip hurst2001 - there are quite a few reasons like that, that the computer will invoke the hard shifting.

donbrew

But, there is a code in this case, and a TSB.

whopper

True - - it will be interesting to see what the outcome is once they throw the Tech II on it, and run the diagnostics etc..