If your 2001–2005 3.3L V6 Chrysler, Dodge, or Plymouth minivan is showing signs of misfire, rough idle, or poor performance, a faulty fuel injector might be the cause.
One of the easiest ways to check a fuel injector's health is by testing its internal resistance with a multimeter.
In this tutorial, I'll show you how to perform a simple, reliable resistance test to check for open or shorted injector coils without having to remove the intake manifold plenum.
It's a straightforward DIY test that can help you avoid unnecessary parts-swapping and get straight to the root of the problem.
Contents of this tutorial:
APPLIES TO: This tutorial applies to the following vehicles:
- 3.3L V6 Chrysler Town & Country: 2001, 2002, 2003, 2004, 2005.
- 3.3L V6 Chrysler Voyager: 2001, 2002, 2003.
- 3.3L V6 Dodge Caravan: 2001, 2002, 2003, 2004, 2005.
- 3.3L V6 Dodge Grand Caravan: 2001, 2002, 2003, 2004, 2005.
NOTE: For the 2005 models listed above, this tutorial only applies to early 2005 models. If you have a late 2005 model, this tutorial does not apply.
Symptoms Of A Bad Fuel Injector
Fuel injectors generally fail in two specific ways:
- Electrical failure (open or shorted coil): Some fail electrically —when the internal coil winding breaks or shorts out.
- Restricted flow (clogged or dirty): Others become clogged from carbon buildup or poor-quality fuel.
You may also run into issues with the injector harness, connectors, or the PCM's injector driver circuit not activating the injector properly.
Some of the most common symptoms of a bad fuel injector include:
- Rough idle: The engine may stumble or shake while idling, especially when cold.
- Misfire: You may feel hesitation or jerking under load or during acceleration. A dead injector can cause one cylinder to go completely inactive.
- Misfire trouble codes: You may 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.
- Loss of power: A weak or non-functioning injector can starve a cylinder of fuel, reducing overall performance and efficiency.
- OBD2 trouble codes: Common codes include misfire codes (like P0300 through P0306), or even lean condition codes like P0171 if one side of the engine isn't getting enough fuel.
A bad or clogged fuel injector can cause drivability problems that are easy to mistake for ignition or sensor issues.
That's why testing is key —and one of the first steps is checking the injector's internal resistance to confirm it's electrically sound.
If it fails the resistance test, there's no need to dig further —the injector needs to be replaced.
10 Pin Fuel Injector Wiring Harness Connector Pinout
To check the resistance of the fuel injectors, we're going to take our measurements from the 14-pin fuel injector wiring harness connector —specifically, the one with the female spade terminals.
Here are the terminal pin IDs you'll need to test the fuel injectors:
- Terminal 1: 12 Volt Feed.
- Brown with white stripe (BRN/WHT) wire.
- Terminal 3: Injector #1.
- Brown with yellow stripe (BRN/YEL) wire.
- Terminal 4:Injector #2.
- Brown with dark blue stripe (BRN/DK BLU) wire.
- Terminal 5: Injector #3.
- Brown with light blue stripe (BRN/LT BLU) wire.
- Terminal 6: Injector #4.
- Brown with tan stripe (BRN/TAN) wire.
- Terminal 8: Injector #5.
- Brown with orange stripe (BRN/ORG) wire.
- Terminal 9: Injector #6.
- Brown with violet stripe (BRN/VIO) wire.
TEST 1: Checking Fuel Injector Resistance
Each fuel injector contains a small internal coil winding. When the injector receives 12 Volts and Ground, this coil energizes, causing the injector to open and spray fuel into the intake port.
But over time, this coil winding can fail —either by shorting out or breaking internally (open-circuit). When that happens, the injector stops working and no fuel gets delivered to that cylinder.
We can easily test the condition of each fuel injector's internal coil by measuring its resistance with a multimeter.
On this 3.3L V6 engine, all six fuel injectors are located under the intake manifold plenum and the cool thing is that you don't need remove the plenum to test them.
If you don't have a multimeter or need to upgrade yours? This is the one I use and recommend: Tekpower TP8268 AC/DC Auto/Manual Range Digital Multimeter (at: amazon.com).
NOTE: This test must be done with a cold engine. The fuel injector resistance specification assumes the injector is at room temperature —but whatever the ambient temperature is in your location will work fine.
These are the test steps:
- 1
Disconnect the 10-pin fuel injector wiring harness connector.
NOTE: All resistance tests are performed at the harness connector, which contains the female spade terminals. - 2
Set your multimeter to Ohms (Ω) mode.
- 3
To test injector #1, probe terminals 1 and 3 with your multimeter leads.
NOTE: Use the connector pinout chart to confirm wire colors and terminal positions: 10-Pin Fuel Injector Wiring Harness Connector Pinout. - 4
To test injector #2, probe terminals 1 and 4.
- 5
To test injector #3, probe terminals 1 and 5.
- 6
To test injector #4, probe terminals 1 and 6.
- 7
To test injector #5, probe terminals 1 and 8.
- 8
To test injector #6, probe terminals 1 and 9.
- 9
Your multimeter should read between 10 and 16 Ohms for each injector.
Let's interpret your test result:
CASE 1: All fuel injectors tested within the specified range of 10–16 Ohms. This is the correct test result and indicates the injector coils don't have an electrical issue (short or open).
Your next step is to check and see if the fuel injector actually sprays fuel and if it does, that it's spray pattern is cone-shaped:
CASE 2: One or more fuel injectors did not fall within the 10–16 Ohm range. This is a failed test result —the injector that tested outside the specified range is faulty and should be replaced.
CASE 3: One or more fuel injectors read as an open-circuit (OL on your multimeter). This means the injector is electrically dead and no longer capable of functioning. Replace the failed injector(s).
More 3.3L V6 Chrysler, Dodge, And Plymouth Minivan Tutorials
I've written several more tutorials for the V6 Chrysler, Dodge, and Plymouth minivans that you might find helpful. You can browse them all in this index:
If this info saved the day, buy me a beer!
