Oct 192016
 

2001 Chevy CavilierIt lets me shift from first to second but no other gears. Can I bleed my clutch or do I need a whole new clutch kit?


RESPONSE

If in neutral with the engine off you are able to shift into all gears then you will need to replace the hydraulic clutch assembly and possibly the clutch slave cylinder assembly. If you are still unable to shift into all gears, there is internal transmission damage.

Hydraulic Clutch System Description and Operation

Clutch Spin Down Time

Check the clutch spin down time as follows:
•Apply the parking brake. Block the vehicle wheels.
•Shift the manual transmission into neutral.
•Start the engine. Run the engine at idle speed.
•Engage the clutch.
•Disengage the clutch. Wait 9 seconds.
•Shift the transmission into reverse.

Clutch Driving Members

The clutch driving members are 2 flat surfaces machined to a smooth finish. They are:
•The rear face of the engine flywheel
•The front face of the clutch pressure plate

Clutch Driven Members

The driven member is the clutch driven plate. The clutch driven plate has a splined hub. The splined hub slides lengthwise along the splines of the input shaft. The splined hub drives the input shaft through these same splines. The driving and driven members are held together with a spring pressure. This pressure is exerted by a diaphragm spring in the clutch pressure plate.

Hydraulic Clutch Fluid

Caution! Do not use mineral or paraffin-base oil in the clutch hydraulic system. These fluids may damage the rubber parts in the cylinders.

Hydraulic Clutch Operating Members

The clutch system consists of the following components:
•A master cylinder with a reservoir
•A switch
•An concentric slave cylinder connected to hydraulic tubing
•Pressure Plate
•Clutch Cover
•Diaphragm Springs
•Release Bearing
•Clutch Disc
•Torsional Springs
•With the depression of the clutch pedal, the clutch master cylinder becomes pressurized from the force of the push rod into the master cylinder. This forces hydraulic fluid into the tubing from the master cylinder to the concentric slave cylinder. The concentric slave cylinder then engages by pushing the releasing bearing into the diaphragm spring and release the clutch. A hole in the cowl panel accommodates the master cylinder. A quick connect coupling helps route the hydraulic tubing. the concentric slave cylinder is inside the transmission and on the input bearing retainer. The hydraulic control system can be replaced without having to gain access to the clutch system internal components , simply engage the quick connect coupling mounted through the transmission housing. No adjustments to the clutch system are necessary. as the clutch wears, the fluid level in the master cylinder reservoir changes to compensates for clear wear. A new system will have fluid in the reservoir. An electrical switch on the push rod has two functions: One function is a clutch interlock, ensuring the engine does not start unless the clutch pedal is engaged, positioned to the floor. The second function is to cut off the cruise-control system, if equipped, when the clutch pedal is engaged.

Oct 182016
 

2002 Chevy TrailblazerFront brakes engage while driving at any speed mainly hwy


RESPONSE

Sounds like you may have a sticking brake caliper. The brake would tend to drag and become worse the longer you drive. It would not be as noticeable when first driving until it has a chance to heat up and expand. Your vehicle is equipped with ABS. Is the ABS light on? If the ABS light is illuminated there may be an issue with your hub bearing failing. This is quite common.

Disc Brake System Description and Operation

System Component Description

 The disc brake system consists of the following components:

Disc Brake Pads: Applies mechanical output force from the hydraulic brake calipers to friction surfaces of brake rotors.

Disc Brake Rotors: Uses mechanical output force applied to friction surfaces from the disc brake pads to slow speed of tire and wheel assembly rotation.

Disc Brake Pad Hardware: Secures disc brake pads firmly in proper relationship to the hydraulic brake calipers. Enables a sliding motion of brake pads when mechanical output force is applied.

Disc Brake Caliper Hardware: Provides mounting for hydraulic brake caliper and secures the caliper firmly in proper relationship to caliper bracket. Enables a sliding motion of the brake caliper to the brake pads when mechanical output force is applied.

System Operation

 Mechanical output force is applied from the hydraulic brake caliper pistons to the inner brake pads. As the pistons press the inner brake pads outward, the caliper housings draw the outer brake pads inward. This allows the output force to be equally distributed. The brake pads apply the output force to the friction surfaces on both sides of the brake rotors, which slows the rotation of the tire and wheel assemblies. The correct function of both the brake pad and brake caliper hardware is essential for even distribution of braking force.
Oct 162016
 

2000 Chevy SilveradoRepair cause of oil leak at oil filter block leading to radiator.


RESPONSE

The leak is coming from the Engine Oil Cooler block. You will need to remove the two retaining bolts from the cooler block and replace the gasket. This is a common gasket failure.

Engine Oil Cooler Description and Diagram

The oil cooler is located in the left side of the radiator. Engine oil flows through the cooler and reduces the temperature of the engine oil. The cooled engine oil then returns to the engine.

Engine Oil Cooler Diagram 2000 Chevy Silverado 6.0L

Here is the gasket you need for under $10. I double checked to make sure it will fit on your specific engine.

Oct 152016
 

2013 Chevy SilveradoWill it damage my truck if I up-size my rims from the factory 17″ to 20″ rims ????


RESPONSE

It will not damage the truck. The outside tire diameter should remain the same. This will ensure the speedometer readings will not change. However you will find that the steering will be affected at park and slower speeds. It may be more difficult to steer when parking and moving from park. The factory power steering pump is not designed to work with the extra tread that will be exposed to the ground surface. Other than that, smooth sailing. You can avoid this if your 20″ tires do not exceed the factory width. 20′ Rims were an option for this vehicle.

I tried this on a 2006 Chevy Silverado and it was bothersome enough that I removed the 20″ rims and sold them. I put the factory 17″ rims back on. They don’t look as good, but no steering issues is worth it to me.

Oct 122016
 

2000 Chevy ImpalaMy 2000 Chevy Impala has become very sluggish. It almost has no take off power, starting to die and really hard to start.


RESPONSE

Start with pulling any check engine light codes and post them below for more information. Check for need of tune up. If you have recently changed fuel stations, it may be related to the fuel. A hard start issue can be attributed to a leaking fuel pressure regulator. This is usually accompanied by a gasoline smell.

2000 Chevy Impala Fuel Pressure Regulator Replacement

2000-chevy-impala-fuel-pressure-regulator-replacement
Oct 102016
 

2011 Chevy TraverseMy ecm1 fuse keeps blowing. The car will not start. What should I do?


RESPONSE

Check the Powertrain relay first. Trace wiring from relay yo fuse and from fuse to the ECM and look for a short. If it checks out you may need to replace the ECM. The wiring diagram below shows the ECM 1 Fuse and wiring. It connects to the ECM from there.

ECM Fuse 1 Wiring Diagram 2011 Chevy Traverse

2011-chevy-traverse-ecm-1-fuse-color-schematics-engine-controls-3-6l-vin-d-4-of-6
Oct 012016
 

1999 Chevy Z71My driver rear park light and tag light not working. fuse is good. replaced lamps. still not coming on.


RESPONSE

  1. Check for power and ground at the bulb socket. Yes – replace bulb. No – go to next step.
  2. Check for power and ground at the tail light assembly connection. Yes – Replace tail light assembly. No – see next step.
  3. Clean and repair all grounds.
  4. Still no power to tail light assembly. No – check relays if equipped.
  5. Check Switch
  6. Check connections and wiring. Check Trailer Tow wiring and connection. Repair as needed.

Use the wiring diagram provided to help trace your wiring.

1999 Chevy Truck Tail Light Wiring Diagram

1999-chevy-truck-exterior-lights-exterior-lamps-circuit-1-of-1

 

Sep 282016
 

2005 Chevy SilveraoI have diagnostic trouble code P1125 come up what does it mean?


RESPONSE

Code P1125 – Accelerator Pedal Position Sensor Fault

The accelerator pedal position (APP) sensor 1 and the APP sensor 2 are potentiometer type sensors, each with the following circuits:

• A 5-volt reference circuit

• A low reference circuit

• A signal circuit

The control module provides the APP sensors with a 5-volt reference circuit and a low reference circuit. The APP sensors then provide the control module signal voltages proportional to pedal movement. The APP sensor 1 signal voltage is low at rest and increases as the pedal is depressed.

The APP sensor 2 signal voltage is low at rest and increases as the pedal is depressed. When the control module detects that the APP sensor 1 and the APP sensor 2 signal circuits are out of correlation with each other, DTC P1125 sets.

The Powertrain Control Module (PCM) detects that the difference between Accelerator Pedal Position (APP) sensor 1 and APP sensor 2 is more than the predicted value.

Code P1125 Possible causes

– Faulty Accelerator Pedal Position Sensor
– Accelerator Pedal Position Sensor harness is open or shorted
– Accelerator Pedal Position Sensor circuit poor electrical connection

Code P1125 Diagnostic Chart

Circuit Description

The accelerator pedal position (APP) sensor 1 and the APP sensor 2 are potentiometer type sensors, each with the following circuits:

A 5-volt reference circuit
A low reference circuit
A signal circuit

The control module provides the APP sensors with a 5-volt reference circuit and a low reference circuit. The APP sensors then provide the control module signal voltages proportional to pedal movement. The APP sensor 1 signal voltage is low at rest and increases as the pedal is depressed. The APP sensor 2 signal voltage is low at rest and increases as the pedal is depressed. When the control module detects that the APP sensor 1 and the APP sensor 2 signal circuits are out of correlation with each other, Code P1125 sets.

Conditions for Running the Diagnostic Trouble COde

DTC P1518, P2108 or U0107 is not set.
The ignition is in the Crank or Run position.
The ignition voltage is more than 5.23 volts.
The communication between the throttle actuator control (TAC) module and the powertrain control module (PCM) must be valid.

Conditions for Setting the DTC

The PCM detects that the difference between APP sensor 1 and APP sensor 2 is more than the predicted value.

Action Taken When the DTC Sets

The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
The control module commands the TAC system to operate in the Reduced Engine Power mode.
A message center or an indicator displays Reduced Engine Power.
Under certain conditions the control module commands the engine OFF.

Conditions for Clearing the MIL/DTC

The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
Clear the MIL and the DTC with a scan tool.
Step Action Values Yes No
Schematic Reference: Engine Controls Schematics

Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module Connector End Views

1 Did you perform the Diagnostic System Check – Engine Controls? Go to Step 2 Go to Diagnostic System Check – Engine Controls
2 Record the throttle actuator control (TAC) module calibration with a scan tool.

Does the TAC module calibration match the part number of the TAC module?

Go to Step 3 Go to Step 11
3 Observe the DTC Information with a scan tool.

Is DTC P2120 or P2125 also set?

Go to Diagnostic Trouble Code (DTC) List Go to Step 4
4
  1. Turn OFF the ignition for 30 seconds.
  2. Turn ON the ignition, with the engine OFF.
  3. Observe the APP Sensors 1 and 2 parameter with a scan tool.

Does the scan tool indicate that the APP sensors 1 and 2 parameters disagree?

Go to Step 5 Go to Intermittent Conditions
5
  1. Turn OFF the ignition.
  2. Disconnect the accelerator pedal position (APP) sensor.
  3. Disconnect the TAC module.
  4. Measure the resistance of the following circuits for each of the APP sensors with a DMM:
The low reference circuit
The signal circuit
The 5-volt reference circuit

Is the resistance more than the specified value for any circuit?

5 ? Go to Step 9 Go to Step 6
6 Test the signal circuit of the APP sensor 1 for a short to the signal circuit of the APP sensor 2. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 12 Go to Step 7
7 Test for an intermittent and for a poor connection at the TAC module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 12 Go to Step 8
8 Test for an intermittent and for a poor connection at the APP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 12 Go to Step 10
9 Repair the high resistance in the circuit that measured above the specified value. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 12
10 Replace the APP sensor. Refer to Accelerator Pedal Position Sensor Replacement.

Did you complete the replacement?

Go to Step 12
11 Replace the TAC module. Refer to Electronic Throttle Actuator Control Module Replacement.

Did you complete the replacement?

Go to Step 12
12
  1. Assemble the vehicle, as necessary.
  2. Clear the DTCs with a scan tool.
  3. Start the engine.
  4. Operate the system in order to verify the repair.

Did the DTC fail this ignition?

Go to Step 2 Go to Step 13
13 Important: Be aware that repairing one individual condition may correct more than one DTC.

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

Go to Diagnostic Trouble Code (DTC) List System OK