In this tutorial, I'll explain how to test the fuel injectors on the 2007 and 2008 3.5L Chevrolet Malibu.
Even though most of the injectors are located underneath the intake manifold plenum, you don't have to remove it to test them!
With your test results you'll be able to find out if any of the 6 fuel injectors are fried internally (or not).
Contents of this tutorial at a glance:
You can find this tutorial in Spanish here: Cómo Probar Los Inyectores (2007-2008 3.5L Chevrolet Malibu) (at: autotecnico-online.com).
NOTE: You can find the fuel injector tests for the 2004-2006 3.5L Chevrolet Malibu here: How To Test The Fuel Injectors (2004-2006 3.5L Malibu).
Symptoms Of A Bad Fuel Injector
As you're already aware, each of the six cylinders of your Chevy Malibu's 3.5L V6 engine needs compression (air), fuel, and spark to produce power.
The fuel injector is the one that's tasked with injecting fuel into the cylinder. When one of them fails, that cylinder will go dead and you're going to see one or more of the following fuel injector trouble codes:
- P0201: Injector 1 Control Circuit.
- P0202: Injector 2 Control Circuit.
- P0203: Injector 3 Control Circuit.
- P0204: Injector 4 Control Circuit.
- P0205: Injector 5 Control Circuit.
- P0206: Injector 6 Control Circuit.
In the majority of the cases, you won't see a fuel injector trouble code but a cylinder misfire trouble code. When this happens you'll see one or more of the following:
- P0300: Random Cylinder Misfire.
- P0301: Cylinder #1 Misfire.
- P0302: Cylinder #2 Misfire.
- P0303: Cylinder #3 Misfire.
- P0304: Cylinder #4 Misfire.
- P0305: Cylinder #5 Misfire.
- P0306: Cylinder #6 Misfire.
Besides a fuel injector or cylinder misfire trouble code, you're also going to notice one or more of the following symptoms:
- Rough idle.
- Bad gas mileage.
- A heavier than usual exhaust gas smell coming out of the tailpipe.
- Lack of power when accelerating the vehicle under load.
Location Of The Fuel Injector Harness Connector
5 of the 6 fuel injectors are underneath the intake manifold plenum on the 2007-2008 3.5L Chevy Malibu. The cool thing is that we don't have to remove it to test their internal resistance.
We can test the internal resistance of each fuel injector through the fuel injector harness connector (the arrow in photo 1 of 3 above points to this connector).
The fuel injector harness connector is located on the right/front side of the intake manifold plenum. Right near the mass airflow sensor see photo 1 of 3 above.
We'll be performing our tests on the connector that belongs to the fuel injector harness itself. This connector has male spade terminals as you can see in photo 2/3 and photo 3/3 in the image viewer above.
Where To Buy The Fuel Injectors And Save
The following links will help you comparison shop for the fuel injectors:
Not sure if the fuel injector will fit your particular GM vehicle? Don't worry, once you get to the site, they'll make sure it fits. If it doesn't, they'll find you the right one.
TEST 1: Testing The Fuel Injector Resistance
On the 2007-2008 3.5L Chevrolet Malibu, the fuel injector resistance specification is: 10 to 15 Ohms with a cold engine.
If any of the fuel injectors is internally damaged or defective, then it's internal resistance will not be within the specified 10 to 15 Ohms.
These are the test steps:
- 1
Place your multimeter in Ohms mode.
- 2
Disconnect the fuel injector harness from the engine wiring harness connector.
NOTE: All tests are done on the fuel injector harness connector which has male spade terminals. - 3
Probe terminals A and C with the multimeter test leads to test injector #1.
Your multimeter should register 10 to 15 ohms. - 4
Probe terminals A and D with the multimeter test leads to test injector #2.
Your multimeter should register 10 to 15 ohms. - 5
Probe terminals A and E with the multimeter test leads to test injector #3.
Your multimeter should register 10 to 15 ohms. - 6
Probe terminals A and F with the multimeter test leads to test injector #4.
Your multimeter should register 10 to 15 ohms. - 7
Probe terminals A and G with the multimeter test leads to test injector #5.
Your multimeter should register 10 to 15 ohms. - 8
Probe terminals A and H with the multimeter test leads to test injector #6.
Your multimeter should register 10 to 15 ohms.
Let's examine your resistance test results:
CASE 1: The resistance of all 6 fuel injectors is within specification. This is the correct and expected test result and confirms that the fuel injectors are not defective internally.
CASE 2: One or more fuel injectors' resistance value is not within specification. This let you know that that fuel injector or fuel injectors are defective internally and need to be replaced.
