2005 GMC Envoy SLT - Answered Questions & Fixed issues

I wonder if the Immobilizer is related to the door locks and the fuse blowing broke the pairing. Try the reset https://www.google.com/search?q=2005+GMC+Envoy+SLT+reset+security ..

Do you have a code number? otherwise more commonly found when you have just reverse is a cracked cage in the transmission,the good thing is it is a cheap fix.

Yes, if you didn't see it from the fuel lines coming from the tank along the frame rail, it's integrated into the fuel pump which is inside the gas tank. I believe 04 was the last year of the external fuel filters for Envoys and Trailblazers.

Hi Karen, easy easy, think you already read one of my fixes for this on another post...... Clean your throttle body with the battery disconnected. Will fix your problem, need to clean the Throttle body at least once a year. You'll get better gas mileage too.

on top of motor in the back

Someone will need to get behind the dash and check the blend doors for operation. It could be a blend door or the main controller.

The secondary air system is a system where an air pump puts extra air into the exhaust system for better emissions.It has nothing to do with the cooling system.The MAP sensor measures intake manifold vacuum to help tell the computer how much fuel the engine needs.

How to install a seatbelt in a 2007 GMC envoy in the passenger side

Might be a short in the wiring in the column or the horn pad.Or in the engine compartment.

try changing out the PCM. its responsible for transmission operation. bad PCM means dumb transmission.

Firing order is 1, 5, 3, 6, 2, 4. Number 1 cylinder is up front. Why would you need the firing order, this engine does not have plug wires, each plug has its own coil pack, each coil pack is controlled by the computer.

I did the procedure vehicle still didn't start.I did notice the security light did no blink but stayed solid before it when out.Im lost ..

Picture would be perfect.

Your drive train may be in limp mode, which indicates something seriously wrong with it (engine or transmission). Check for trouble codes with a code reader.

Google your question. About 280,000 results (0.61 seconds) https://www.autozone.com/repairguides/S-T-Series-Blazer-Bravada-Envoy-Jimmy-Rainier-Trailblazer-Xtreme/Component-Locations/Secondary-Air-Injection-AIR-Pump-Relays/_/P-0996b43f80cb36eb

Look for black wire. Check it by using an omh meter and testing it to a ground.

Check youtube for video

Have you checked the fusible links running off the starter connection at the starter?

located in the back . It's called the LGM fuse #2 (Lift Gate Module) The Lift Gate Module controls the defroster grid circuit.

threw a po128 ??? Doesn't throw code's ,it stores code's . P0128 code does not tell you to replace the sensor either . With every code comes a diagnostic test procedure listed in a factory info. manual . DTC P0128: Engine Coolant Temperature (ECT) Below Thermostat Regulating Temperature The purpose of this diagnostic is to analyze the performance of the thermostat, by using the ECT sensor to determine if the engine coolant will increase at the correct rate, and also meet the calibrated target temperatures under various operating conditions. The ECM uses the start-up ECT and the start-up intake air temperature (IAT) to begin the diagnostic calculation. The air flow into the engine is accumulated, and vehicle speed, distance, and engine run time are also factored in to determine if the ECT does increase normally and reach the calibrated target temperatures. Diagnostic Aids ?€¢ DTC P0128 occurring with insufficient vehicle interior heating is an indication of improper thermostat operation.

?€¢ Corrosion in the ECT sensor terminals or the ECT harness connector results in a greater voltage on the ECT sensor signal circuit, which is interpreted by the ECM as a colder ECT.

?€¢ A slight to moderate resistance in the ECT sensor signal circuit or low reference circuit will affect this diagnostic. This condition results in a greater voltage on the ECT sensor signal circuit, which is interpreted by the ECM as a colder ECT.

Circuit/System Verification

1. Ignition OFF, inspect the cooling system surge tank for the proper coolant level. Refer to Cooling System Leak Testing and Cooling System Draining and Filling .
2. Ignition OFF for 8 hours or greater.
3. Ignition ON, observe the scan tool ECT Sensor and IAT Sensor parameters. The ECT, IAT and ambient temperatures should be within 15?°C (27?°F) of each other.
Important: A critical analysis of the operation of the thermostat is necessary to properly diagnose this DTC.
4. Verify the proper heat range, and the operation of the thermostat. Refer to Thermostat Diagnosis .
5. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the ECT sensor.
2. Ignition OFF for 90 seconds, test for less than 5 ohms between the low reference circuit terminal B and ground.
?‡' If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
3. Ignition ON, verify the scan tool ECT Sensor parameter is colder than -39?°C (-38?°F).
?‡' If warmer than the specified range, test the signal circuit terminal A for a short to ground. If the circuit tests normal, replace the ECM.
4. Install a 3A fused jumper wire between the signal circuit terminal A and the low reference circuit terminal B. Verify the scan tool ECT Sensor parameter is warmer than 149?°C (300?°F).
?‡' If colder than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
5. If the circuits test normal, test or replace the ECT sensor.