Saturn›Ion›2003›Overview/saturn/ion/2003/base/

2003 Saturn Ion

Factory specifications, fluid capacities, torque values, EPA fuel economy and the federal safety record for the 2003 Ion.

Body PASSENGER CARTransmission Automatic (variable gear ratios)

The 2003 Saturn Ion is a passenger car that employs a five‑quart oil capacity of 5W‑30 API and is mated to an automatic transmission with variable gear ratios, delivering EPA‑estimated fuel economy of 21 mpg city, 29 mpg highway and 24 mpg combined. During its early production the model accumulated 766 owner complaints, most frequently concerning the electrical system, and was subject to seven recall campaigns. Complaint records for the 2003‑2008 model run show a high of 1,235 complaints in 2006 and a low of just four in 2008, indicating that the 2003 year falls near the lower end of the complaint curve.

Model year2007 2006 2005 2004 2003

Quick specs

Fluid capacities, tune-up values and fuel economy at a glance.

Engine oil capacity5 qtOEM · verified

Engine oil type5W-30 APIOEM · verified

Lug nut torque100 ft-lbsOEM · verified

EPA fuel economy21/29/24 mpgEPA · verified

Fitment & sizes

Replacement part sizes and factory part numbers — battery, bulbs, filters and belts.

From the factory this vehicle uses a BCI 75 · 600 CCA battery, OE oil filter 12580255. Note the factory engine air filter and fuel filter are now discontinued — plan on a superseded or quality aftermarket equivalent, which the part pages below list where known. Each part links to every other vehicle that shares it, so a part you already stock may fit more of your fleet than you'd expect.

Battery groupBCI 75 · 600 CCAOEM · verified

OE service part numbers OEM · verified

Engine oil filter	12580255 alt 12605566
Engine air filter	22679620 discontinued
Fuel filter	22734980 discontinued
Spark plug	12681663
Front wiper blades	20918023 alt 15245111
Serpentine belt	12634322 alt 12634320
Thermostat	03522676 alt 12622410
Cabin air filter	52493319

Full specifications

Engine, drivetrain, dimensions and economy.

Engine & drivetrain NHTSA vPIC

Transmission

Automatic (variable gear ratios)

Dimensions & weight NHTSA vPIC

Overall length	185 in
Overall width	68.1 in
Overall height	55.9 in
Wheelbase	103.1 in
Curb weight	2751 lb
Track (front / rear)	58.7 / 58.3 in
Weight distribution (front / rear)	60/40

Ratings & economy EPA / vPIC

EPA city / highway / combined	21 / 29 / 24 mpg
Drivetrain	Front-Wheel Drive
Passenger volume	92 cu ft
Cargo volume	15 cu ft
Recommended fuel	Regular Gasoline

Service quick specs OEM factory data

Capacities, torques and tune-up values from the factory service manual.

This engine holds 5 qt of 5W-30 API engine oil, DOT 3 brake fluid. Torque lug nuts to 100 ft-lbs, the oil drain plug to 18.0 ft-lbs. The firing order is 1-3-4-2. Note the cylinder-head bolts finish on a torque angle (torque-to-yield) — they stretch permanently and should be replaced, not reused, during any head service.

Lubricants & capacities

Brake Fluid	DOT 3
Engine Oil	5W-30 · API
Engine Oil Capacity	5 qt

Engine torques

Intake Manifold to Engine Bolts	7.4 ft-lbs
Exhaust Manifold to Cylinder Head Bolts	13 ft-lbs
Engine Oil Pan Drain Plug	18.0 ft-lbs

Chassis torques

Lug Nuts	100 ft-lbs
Front Wheel Hub	81 ft-lbs

Ignition

Cylinder Firing Order	1-3-4-2
Spark Plug Manufacturer	AC Delco
Spark Plug Gap	0.040 in
Spark Plug Torque	18.0-22.0 ft-lbs

Battery & A/C

Refrigerant	R134a
Refrigerant Capacity	.90 lbs
Oil Group	PAG
Oil Type	46
Oil Capacity	5.00 oz
Standard BCI Group Number	75
Standard BCI Cranking Performance	600 cca

Service checks

Injector Primary Resistance	12-13 na ohms
Engine Oil Pressure	65 psi
Engine Oil Pressure RPM	1000 rpm

Brakes

Torque Caliper to Bracket	25 ft-lbs
Torque to Knuckle	85 ft-lbs
Minimum Pad Thickness	0.039 in
Minimum Shoe Thickness	0.020 in
Rotor Max Parallel Variation	0.001 in
Rotor Runout Limit	0.002 in
Rotor Nominal Thickness From	0.933 in
Rotor Nominal Thickness To	0.933 in

Multi-step torque procedures OEM · verified

Crankshaft Pulley and/or Damper Bolts — tightening sequence 1 stages

74 ft. lbs., step 2: 75

74 ft. lbs

Cylinder Head — tightening sequence 2 stages

1	22 ft. lbs.	22 ft. lbs
2	155 degrees.	155 degrees

Factory maintenance schedule OEM · verified

Normal service, condensed from the factory interval matrix.

Under the factory schedule, replace the spark plugs every 100,000 mi; coolant every 100,000 mi. The big-interval services (every 100,000 mi for coolant, and the transmission fluid) are the ones owners most often skip — on a lower-mileage example, assume the original fluids are still in it and check them first.

Every 6,000 mi	Body Latches, Locks & Hinges (lubricate) · Brake System (inspect) · Exhaust System (Complete) (inspect) · Exhaust System Heat Shield (inspect) · Sunroof Assembly (lubricate) · Tire & Wheel Assembly (rotate)
Every 18,000 mi	Accessory Drive Belt (inspect) · Cabin Air Filter (replace) · Engine Coolant System Hoses (inspect) · Vacuum Line (inspect)
Every 30,000 mi	Engine Air Filter Element (replace)
Every 50,000 mi	Transmission Assembly (add fluid conditioner)
Every 100,000 mi	Engine Coolant System (drain, flush & refill) · Fuel Filter (replace) · Spark Plugs (replace)

Reliability & federal safety record

Owner-reported issues, recalls, investigations and service bulletins on record with NHTSA — an unfiltered look at what owners actually experience.

In 2003, the Saturn Ion had 766 complaints, 7 recalls, 5 investigations, and 505 TSBS reports—slightly below the 2004 peak of 898 complaints and 10 recalls, but still a notable number of issues. The following year, 2005 saw a sharp decline to 573 complaints and only 5 recalls, suggesting a brief improvement. By 2006 complaints spiked to 1,235, indicating a resurgence of problems, before moderating again in 2007 to 876 complaints and 7 recalls. The 2008 data, with only 4 complaints and no recalls, reflects a sharp drop, but this is after the 2003 model year. For the 2003 model, the top complaint categories were Electrical System (288), Steering (105), Power Train (39), and Engine & Engine Cooling (39), with 44 crash complaints and 4 fire complaints—moderate but not negligible. Given that 2003 sits near the beginning of a higher‑complaint trend that peaks in 2006, it is a less attractive purchase year unless the vehicle has been well maintained and updated; a newer year may offer fewer issues.

Open recalls

NHTSA campaigns

505

Service bulletins

Manufacturer communications

ODI investigations

Office of Defects Investigation

766

Owner complaints

44 involved a crash · 4 a fire

NHTSA crash-test rating federal NCAP · out of 5 stars

Rollover★★★★★

Owner complaints by model year NHTSA · this generation & adjacent

’03’04 ’05 ’06 ’07 ’08

Owner complaints filed with NHTSA, by component

All 766 complaints on record, top 8 components.

Electrical System288

Steering105

Power Train39

Engine & Engine Cooling39

Air Bags22

Vehicle Speed Control21

Exterior Lighting21

Visibility19

Source: NHTSA Office of Defects Investigation complaint database.

Recalls NHTSA · verified

Showing 2 of 7 campaigns on record for this vehicle.

14V171000Electrical System:IgnitionReported 10/04/2014

General Motors LLC (GM) is recalling certain model year 2005-2010 Chevrolet Cobalt, 2006-2011 Chevrolet HHR, 2007-2010 Pontiac G5, 2006-2010 Pontiac Solstice, 2003-2007 Saturn Ion, and 2007-2010 Saturn Sky vehicles. In… Remedy: General Motors will notify owners, and for vehicles that were built with the defective ignition cylinder and have not previously had the ignition cylinder replaced with the…

14E021000Electrical System:Ignition:SwitchReported 30/04/2014

UCI-FRAM Group is recalling certain LS1328 ignition Switches sold as Wells LS1328, Duralast LS1328, Airtex 1S6097, and Carquest 53-27479, and LS1497 Ignition Switches sold as Wells LS1497, Duralast LS1497, Airtex… Remedy: UCI-FRAM Group has notified its purchasers to quarantine and return all inventory. Any switches already installed in vehicles will be replaced by GM dealers as part of NHTSA…

Technical service bulletins NHTSA · verified

Showing 5 of 505 bulletins on record with NHTSA.

Bulletin	Date	Component	Summary
PIP5601C	2025-07-18	Unknown Or Other	This PI communicates the requirement to provide a pico file to receive diagnostic…
PIP5358D	2025-02-19	Unknown Or Other	This Preliminary Information communication provides information to the technician about…
PIP4723J	2024-10-25	Electrical System	This Preliminary Information communicates to the dealer the process for downloading or…
PIT5099H	2024-09-12	Unknown Or Other	This Preliminary Information communication provides information to the technician about…
PIT5099H	2024-09-12	Unknown Or Other	This Preliminary Information communication provides information to the technician about…

Common OBD-II trouble codes

The most common OBD-II codes for this vehicle's emissions system. These are standardized SAE J2012 definitions, not vehicle-specific fault reports.

P0420

Catalyst system efficiency below threshold — Bank 1

P0300

Random / multiple cylinder misfire detected

P0171

System too lean — Bank 1

P0455

Evaporative emission system leak detected — large leak

P0128

Coolant thermostat below regulating temperature

P0442

Evaporative emission system leak detected — small leak

VIN tools

Decode factory build data for a specific vehicle by VIN.

VIN

Decode a VIN to confirm the transmission and build data for a specific Ion. OEM

Build data

Plant, GVWR class, engine and body data for any 17-character VIN.

Recalls

Check open recall campaigns against a specific vehicle by VIN.

Vehicles with shared specs

Find every vehicle that shares this one's battery, bulbs, oil capacity, platform or parts.

Group 75 battery Vehicles taking 5 qt Engine oil filter 12580255 Engine air filter 22679620 Fuel filter 22734980 Spark plug 12681663

Reference guides

Cross-vehicle references for the kinds of data on this page.

Vehicle recalls & TSBs OBD-II trouble codes Torque specifications Maintenance schedules Fluid capacities & specs

Frequently asked

How much oil does the 2003 Ion take?

5 qt of 5W-30 API, per the factory manual.

Does the 2003 Ion have open recalls?

NHTSA lists 7 recall campaign(s) for this model year. Check your specific vehicle by VIN.

What gas mileage does the Ion get?

EPA figures are 21 city / 29 highway / 24 combined mpg.