2008 PT Cruiser P0113 and P0108 Codes: Diagnosis and Fix for MAP and IAT Sensor Issues

Check the wiring harnesses and circuit integrity for both the MAP and IAT sensors. Poor connections or damaged wires can cause high voltage readings, especially if there's a shared ground.

Are codes P0113 and P0108 occurring simultaneously? Do you have access to a digital volt-ohm meter (DVOM)? What is your engine configuration—specifically, a 2.4L DOHC engine?

Yes, both codes appear at the same time. The engine is a 2.4L DOHC unit. Do I need a digital DC meter? Can I use my Harbor Freight multimeter for testing?

A digital volt-ohm meter (DVOM) is essential for accurate circuit testing. You'll need to perform back-probe tests on the MAP and IAT sensor terminals while the engine is running. Ensure you have jumper pins or test probes available for this.

Are there any Throttle Position Sensor (TPS) fault codes present? A failing TPS can affect both MAP and IAT readings due to shared grounding.

Both P0113 and P0108 indicate high voltage in pressure and temperature sensors. This is typically caused by a poor ground connection. Since the TPS shares a ground with both MAP and IAT, a faulty or corroded ground circuit could be the root cause. Perform ground-to-ground voltage drop testing under engine load to confirm.

I'm planning to do this myself—can't afford professional diagnostics. My Harbor Freight Cen-tec multimeter should work for basic tests, right?

Connect the negative lead of your DVOM to the battery's negative terminal. Use jumper pins to back-probe the black/light blue wire at terminal 2 on both the MAP and IAT sensors while the engine is running (with connector attached). Measure voltage under load. Repeat for each sensor. A healthy ground-to-ground voltage drop should be less than 100 millivolts (0.10 volts).

What driveability issues are you experiencing? For example, stalling, misfiring, or lack of power at higher speeds?

I'm experiencing a complete loss of power. The car was running fine just minutes before—only one block from home—and began misfiring while I was driving. I had enough momentum to coast into my driveway. Two weeks prior, I replaced plugs, wires, and the coil pack (which had a fried #2 terminal).

The engine is still misfiring. I cleared the codes using a scan tool and re-ran the test. The scanner now shows only a Camshaft Position Sensor fault. After replacing that, the engine runs better but still has misfires and no power. A new code P300 appeared—indicating multiple cylinder misfire. This suggests deeper issues like fuel delivery, ignition, or compression problems. I recommend performing full misfire counter diagnostics using your scan tool to identify which cylinders are affected.

I now have a scan tool and cleared the codes. After replacing the camshaft position sensor, the engine runs better but still misfires and lacks power. The only code that appears is P300 (Multiple Cylinder Misfire). This makes me wonder if it's related to ignition or fuel system issues—perhaps a failing coil pack or fuel delivery problem. I'm considering replacing the coil again, but I'd like to know what other diagnostics are recommended before doing so.

Does your scan tool display misfire counters per cylinder? How many miles has the vehicle accumulated? Does the check engine light flash under load? Multiple cylinder misfires (P0300) can stem from ignition, fuel, air, or compression issues. Current and historical misfire counts on a scan tool are critical for diagnosing root causes—this could point to a fuel delivery issue, failing spark plugs, or low compression.