Why is my GM OBD code 34 low?

GM OBD Trouble Code 34 MAP Sensor Circuit Error (Signal Low Indicating High Vacuum) The ECM uses the Manifold Absolute Pressure (MAP) sensor as an indication of engine load. High voltage would indicate low engine vacuum and higher engine load.

What kind of engine does a 1987 GM van have?

Fig. 4: Vacuum hose routing – 1987-88 Federal (VIN H) 5.0L engines with automatic transmissions (G10 and 20 models) Fig. 5: Vacuum hose routing – 1987-88 Federal and high altitude (VIN H) 5.0L and (VIN K) 5.7L engines with automatic transmissions (G10 and 20 models)

What are the GM trouble codes for 2008?

Here is what I have done since Aug. 2008 I have replaced the MAF sensor, air filter, knock sensor, fuel pump, coil, tps, fuel filter, distributor cap and rotor. But guess what I am still having the same codes in this order P0327,P0171, and P0174.

How to repair GM full size vans 1987-1997?

Access our GM Full Size Vans 1987-1997 Vacuum Diagrams Repair Guide by creating an account or signing into your AutoZone Rewards account. Once you sign in, follow these instructions to access our Repair Guides. Add your vehicle in Manage My Vehicles. Enter your vehicle details. Click the “View More” button, and then click “Vehicle Repair Guides.”

How do you test a MAP sensor on a car?

How to Test a MAP Sensor When testing a MAP sensor, first make a preliminary check. The sensor connects to the intake manifold with a rubber hose, depending on your particular application; otherwise it connects directly to intake. When problems arise, it’s more likely that the vacuum hose has failed.

What causes a bad code on a MAP sensor?

Remember that even though the code points to the potential problem, the particular circuit or component involved may not be at fault. Instead, a related component may have triggered the code. For example, in many applications a leaking vacuum hose or a bad throttle position sensor (TPS) may cause a trouble code that points to a faulty MAP sensor.

What does code 34 mean on the ECM?

The ECM uses the information from this sensor to help calculate fuel delivery and spark timing. 34 – MAP sensor circuit error (signal low indicating high vacuum) Engine running lean (not enough fuel, hard starting, lack of power) Due to erratic engine vacuum, other engine performance problems can cause a code 34 to set

When does a S-10 engine signal is too high?

33 – MAP sensor signal voltage was too high (low vacuum) for 5 seconds when throttle opening was under 2%. 34 – MAP sensor signal voltage low – MAP sensor signal voltage was too low (high vacuum) when engine speed was over 1200 RPM, or the throttle angle was above 21% when engine speed was over 1200 RPM.

What’s the diagnostic code for a s 10 engine?

F for at least 4 seconds after the engine had been running for 2 seconds. 16 – System voltage high – Charging system voltage was either below 9 volts or above 17 volts for 10 seconds.

When does the MAP sensor signal show low voltage?

34 – MAP Sensor Circuit Signal Voltage Low (High Vacuum) – When engine speed was between 1700 and 3600 RPM and throttle position angle was less than 1%, the MAP signal showed low voltage (high manifold vacuum) for at least 5 seconds.

Why is the MAP sensor on a GM 2.0L?

Since the fuel injection system on your 2.0L, 2.2L or 2.5L GM equipped vehicle is a speed density system, the MAP sensor is one of the most important sensors the fuel injection computer needs to keep the engine running optimally. When the MAP sensor fails, you’ll see/feel one or more of the following symptoms of a bad MAP sensor:

Why is my GM OBD code 34 low?