The 2003-2011 Chevy Cobalt, Chevy HHR, Pontiac G5, Saturn ION Repair Manual by Haynes covers:

• Chevy Cobalt, 2005-2010
• Chevy HHR, 2006-2011
• Pontiac G5, 2007-2009
• Pontiac Pursuit, 2005-2006
• Saturn ION, 2005-2006

These models are available in 4-door sedan or 2-door coupe body styles, and are powered by transversely-mounted 4-cylinder engines.
Book Excerpt: 2003-2011 Chevy Cobalt, Chevy HHR, Pontiac G5, Pontiac Pursuit, Saturn ION Repair Manual TUNE-UP AND ROUTINE MAINTENANCE

INTRODUCTION This Chapter is designed to help the home mechanic maintain the Chevy Cobalt and Pontiac Pursuit/G5 with the goals of maximum performance, economy, safety and reliability in mind. Included is a master maintenance schedule, followed by procedures dealing specifically with each item on the schedule. Visual checks, adjustments, component replacement and other helpful items are included. Refer to the accompanying illustration of the engine compartment for the locations of various components. Servicing the vehicle, in accordance with the mileage/time maintenance schedule and the step-by-step procedures will result in a planned maintenance program that should produce a long and reliable service life. Keep in mind that it is a comprehensive plan, so maintaining some items but not others at the specified intervals will not produce the same results. As you service the vehicle, you will discover that many of the procedures can - and should - be grouped together because of the nature of the particular procedure you're performing or because of the close proximity of two otherwise unrelated components to one another. For example, if the vehicle is raised for chassis lubrication, you should inspect the exhaust, suspension, steering and fuel systems while you're under the vehicle. When you're rotating the tires, it makes good sense to check the brakes since the wheels are already removed. Finally, let's suppose you have to borrow or rent a torque wrench. Even if you only need it to tighten the spark plugs, you might as well check the torque of as many critical fasteners as time allows. The first step in this maintenance program is to prepare yourself before the actual work begins. Read through all the procedures you're planning to do, and then gather up all the parts and tools needed. If it looks like you might run into problems during a particular job, seek advice from a mechanic or an experienced do-it-yourselfer.

FUEL AND EXHAUST SYSTEMS

THROTTLE BODY | INSPECTION, REMOVAL AND INSTALLATION INSPECTION

1. Verify that the throttle linkage operates smoothly.
2. Remove the air intake duct from the throttle body, open the throttle plate and inspect the throttle body bore for carbon and residue build-up. If it's dirty, clean it with solvent or carburetor cleaner. Make sure that the solvent or carb cleaner is safe for oxygen sensor systems and catalytic converters. CAUTION: Do not clean the throttle motor with solvent. Also, do NOT use a metal brush to clean the bore of the throttle body, which is protected by a special coating. Scrubbing the bore with a stiff brush could ruin the coating. Instead, wipe out the bore with a clean shop rag and a little solvent.
REMOVAL AND INSTALLATION
(Refer to illustrations 12.5 and 12.8) WARNING: Wait until the engine is completely cool before beginning this procedure.
3. Disconnect the cable from the negative battery terminal (see Chapter 5, Section 1).
4. Remove the air intake duct and resonator on 2.2L/2.4L models, remove just the intake hose at the throttle body on 2.0L models (see Section 9). On 2.2L or 2.4L models, remove the engine cover.
5. Disconnect the throttle motor connector (see illustration).
6. Disconnect the vacuum hoses at the throttle body, and the EVAP canister purge hose on 2.0L models.
7. Remove the throttle body mounting bolts and remove the throttle body.
8. Remove the throttle body O-ring (see illustration) and inspect it. If the O-ring isn't cracked, torn or otherwise deteriorated, it's okay to reuse it. But if it's damaged or worn, replace it. (If the vehicle is fairly old, it's a good idea to replace this O-ring regardless of its apparent condition).
9. If necessary, clean the throttle body as outlined in Step 2.
10. Installation is the reverse of removal. Be sure to tighten the throttle body mounting bolts to the torque listed in this Chapter's Specifications.
11. When the battery has been disconnected, the PCM must relearn its former driveability and performance characteristics (see Chapter 5, Section 1 for this procedure).
12. Start the engine and verify that the throttle body operates correctly and that there are no air leaks.

Subject: 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Chevy Cobalt, Chevy HHR, Pontiac G5, Pontiac Pursuit, Saturn ION service, maintenance, repair. ISBN-10: 1620923459 | ISBN-13: 9781620923450 | Haynes 38017