Dec 292017
 

2001 Chevy Monte Carlo

My car surges while driving down the road. There is no check engine light. Have replaced plugs, wires, all coils, fuel filter and had smoke test for vacuum leaks done. Nothing helped. Please help. it is a 2001 Monte Carlo 3.4.


Car surges while driving down the road

Could be a failing ignition control module as this is one of the most common failure components. But may also be something else. A failing sensor. A clogged EGR or catalytic converter. Loose or damaged wiring harness. May also be a transmission issue occurring. Hard to tell without experiencing it for myself if it is engine or transmission related. Makes it even more difficult without any stored codes. Even though there is no check engine light on, there may be codes stored. So make sure you at least have them checked. Take note to see if this only occurs after the engine has warmed up or happens even when cold.

Check your wiring harness

Look at the wiring harness for damaged or brittle wires. Pay close attention tot he wiring and connections at both crankshaft position sensors, camshaft position sensor and Interrupter ring mounted on the back of the balancer.

Crankshaft Position Sensor 2001 Chevy Monte Carlo

Ignition System Modes of Operation

Anytime the PCM does not apply 5 volts to the Ignition Control timing signal circuit, the Ignition Control Module controls ignition by triggering each coil in the proper sequence at a pre-determined dwell. This is called Bypass Mode ignition used during cranking and running below a certain rpm, or during a default mode due to a system failure.

When the PCM begins receiving 24x reference and 3X reference pulses, the PCM applies 5 volts to the IC timing signal circuit. This signals the IC module to allow the PCM to control the dwell and spark timing. This is IC Mode ignition. During IC Mode, the PCM compensates for all driving conditions. If the IC mode changes due to a system fault, the IC mode will stay in default until the ignition is cycled OFF to ON, or the fault is no longer present.

Powertrain Control Module – PCM

The PCM is responsible for maintaining proper spark and fuel injection timing for all driving conditions. Ignition control (IC) spark timing is the method the PCM uses to control spark advance and ignition dwell. To provide optimum driveability and emissions, the PCM monitors input signals from the following components in calculating ignition control (IC) spark timing:

  • Ignition control (IC) module
  • Engine coolant temperature (ECT) sensor
  • Intake air temperature (IAT) sensor
  • Mass air flow (MAF) sensor
  • Internal Mode or PNP inputs from Internal Mode switch or Park/Neutral position switch
  • Throttle position (TP) sensor
  • Vehicle speed (VSS), or transmission output speed (TOSS) sensor
Dec 272017
 

Pontiac Grand Prix

I put windshield washer fluid in my coolant tank. Is it safe to drive and is it a big deal? I put a gallon in.


Washer Fluid in Coolant

No. It is not safe to drive the vehicle this way. The engine is capable of overheating. Internal engine damage may occur.

You may be able to drain or suck out the the contaminated coolant. This is if you haven’t started the engine and only filled the reservoir. Disconnect the tank, drain it and put fresh coolant in it. No worries. Washer fluid is basically 95% water, 4% alcohol, .5% soap, and a .5% surfactant. The alcohol will evaporate. The surfactant and soap does not amount to much and there is water in your fluid already.

Coolant Flushing

DO NOT USE A CHEMICAL FLUSH

When the cooling system becomes contaminated, the cooling system should be flushed thoroughly to remove the contaminants before the engine is seriously damaged.

  • Drain the cooling system.
  • Remove the coolant recovery reservoir
  • Clean and flush the coolant recovery reservoir with clean, drinkable water.
  • Install the coolant recovery reservoir.
  • Follow the drain and fill procedure using only clean, drinkable water.
  • Run the engine for 20 minutes.
  • Stop the engine.
  • Drain the cooling system.
  • Repeat the procedure if necessary, until the fluid is nearly colorless.
  • Fill the cooling system.

 

Dec 272017
 

Infiniti G35

I have a power steering issue where the fluid level drops dramatically once car has been driven for 40-45 minutes (to the point the reservoir is almost empty). The strange part is the fluid returns to the reservoir over a short period of time after shutting engine down. No visible leaks on the system. Possible air being sucked in? I’ve checked and don’t see a lot of bubbling or froth in the system when this happens. I’ve bled the systems several times.


Power Steering Fluid Level

The power steering system holds 1.15 quarts of Nissan Power Steering fluid or equivalent.

The fluid level should be checked with the engine off. Check for generation of air bubbles and cloud in fluid. When none are found, you are good. If bubbles or cloud are noticed then the system needs to be bled.

If air bubbles and cloud don’t fade, stop engine, hold air bleeding until air bubbles and cloud fade. Then bleed again until no air bubbles return. Each time holding until the bubbles fade.

Air Bleeding Power Steering System

  1. Stop engine, and then turn steering wheel fully to the right and left several times.
  2. Run engine at idle speed. Turn steering wheel fully to the right and then fully to the left, and keep for about three seconds. Then check whether any fluid leakage occurred.
  3. Repeat several times at about three second intervals.
  4. Check for bubble generation or cloud in fluid.
  5. If air bubbles and the cloud don’t fade, stop engine, hold off on air bleeding until air bubbles fade. Perform the 2nd and 3rd procedures again.
  6. Stop engine, check fluid level.

 

Dec 232017
 

2002 Chevy Silverado

I drove my 2002 Chevy Silverado 2500HD Duramax Diesel about month a and a half go with no problems. I went to take the truck out today, it started right up and I let in warm up for about five minutes. When I went to back out of the garage there was no power steering and no power brakes. Serpentine belt is on and no signs of any leaks. The power steering fluid is full and brake fluid full. Any ideas what might be wrong. Truck has only 76,000 miles on it.


Hydro-boost Testing

Fluid level good: Check tension and condition of drive belt. If the drive belt is loose or damaged, tighten or replace as required and repeat the basic test (Steps 1-2). If pump speed is slow, adjust and repeat basic test. If pump speed is OK, perform pump flow and relief pressure test.

Perform Basic Test:

  1. Engine (pump) off, depress and release the brake pedal four times to deplete all hydraulic pressure from hydo-boost.
  2. Depress brake pedal and hold with light pressure then start the engine. If the power section is operating properly the pedal will fall slightly and then hold. Less pressure will be needed to hold the pedal in this position. If the power section is NOT operating, go to step 3, otherwise go to step 4.
  3. If power section is not operating properly, check pump reservoir level. If level is low, add fluid and repeat basic test plus Hydraulic Leak Test (Steps 4 to 5). If fluid level is good, go to step 6.
  4. Steering Hydraulic Leak Test: Thoroughly clean the hydo-boost unit and all hose connections. Start the engine and run at idle speed. If the hose fittings do not leak go to step 5.
  5. Check the hydro-boost for leaks. Apply the brake pedal with approximately 100 lbs. force and hold while checking hydro-boost hose fittings for leaks. Do not hold brake pedal at 100 lbs. effort for more than five seconds at a time. If the hydo-boost leaks, it is defective and should be replaced or repaired. If no leaks are found in the hydro-boost or hoses, do not repair or replace them.
  6. Fluid level good: Check tension and condition of drive belt. If the drive belt is loose or damaged, tighten or replace as required and repeat the basic test (Steps 1-2). If pump speed is slow, adjust and repeat basic test. If pump speed is OK, perform pump flow and relief pressure test.
  7. If pump output is below minimum specification, replace and repeat basic test. If all test and checks are OK, the booster is defective and should be replaced or repaired.
  8. If power section is operating, perform the following steps in order.
  9. Hydro-boost accumulator pressure retention test: Run pump to medium speed, apply brake pedal force to 100 lbs. for not more than five seconds and then stop engine.
  10. Wait 90 seconds and apply the brakes. Two or more applications should be power assisted. If applications are not power assisted the hydro-boost is defective and should be replaced or repaired. If applications are power assisted, go to next step.
  11. Thoroughly clean the hydo-boost unit and all hose connections. Start the engine and run at idle speed. If the hose fittings do not leak, go to step 5.
  12. Check the hydro-boost for leaks. Apply the brake pedal with approximately 100lbs force and hold while checking hydro-boost hose fittings for leaks. Do not hold brake pedal at 100 lbs. effort for more than five seconds at a time. If the hydo-boost leaks, it is defective and should be replaced or repaired. If no leaks are found in the hydro-boost or hoses, do not repair or replace them. Perform the brake hydraulic leak test.
  13. Brake Hydraulic Leak Test – Depress and release brake pedal several times, then hold pedal depressed with medium pressure of 25 to 35lbs. If pedal does not fall away, hydraulic system is not leaking. If pedal falls away, go to next step.
    Pedal falls away under constant pressure – hydraulic brake system is leaking. Check for external leaks at wheel cylinders, calipers, hoses and lines. If no leaks are found, additional diagnostic steps are necessary.
Service

The hydro-boost in not serviceable in the field. If the unit is not functioning properly, it must be replaced. The replacement process is straight forward, but bleeding can sometimes be tricky. I am offering a choice of techniques in this area. Hydro-boost brake systems are supposed to be self-bleeding, but this does not always prove to be true.
Source: www.brakeandfrontend.com/operation-diagnosis-and-repair-of-hydro-boost-power-assist-systems/

Dec 222017
 

2013 Chrysler 200

Both headlights have stopped working


Headlights stopped working

If you know both were working then I would start with checking the fuses. If one was out and now both, start with replacing the headlights. There are 3 fuses to check. Check fuse #33, #17 and #12. Once you confirm the fuses are good, test for power and ground at the headlights.

Good power and ground means replace the headlamps. Still now power, check the multi-function switch. If that checks out then you are left with the Power module or wiring. I’ll supply you with a wiring diagram to help assist you with the problem.

Headlight wiring diagram – 2013 Chrysler 200

(best viewed with Google Chrome or Firefox)
2013-chrysler-200-color-schematics-headlights-1-of-1

Dec 202017
 

2009 VW Jetta

We are considering purchasing this 2009 VW Jetta 2.5 with 76000 miles on it. First of all it had the EPC light on the instrument cluster when we got to the dealer. So they said they replaced 1 spark plug & coil pack & the light went out. Does this repair sound appropriate or should we be concerned there could be something more serious wrong with the car?
Thanks Phil


Seems like you should be concerned that there is something more serious going on! I would move on to a different vehicle for sure. Most of all the EPC light has nothing to do with the spark plugs or coil packs. Therefore I would suggest looking at something else unless you are completely in love with it. And the dealer is willing to WARRANTY the vehicle.

EPC Light – Electronic Power Control Warning Light

If a malfunction is recognized in the EPC system, the ECM switches on the the EPC warning light.

For EPC, the throttle valve is not operated by a cable from the accelerator pedal. There is no mechanical connection between the accelerator pedal and the throttle valve. The EPC is a system containing all components that contribute to recognizing, controlling and monitoring the position of the control valve.

EPC loation diagram 2009 VW Jetta

Dec 192017
 

Jeep Grand Cherokee Laredo

I replaced my brake booster. Now my lock on the driver side won’t lock all the doors like it should. My keyfob stopped working and my dome lights stay on. Is this a coincidence or did I maybe bump something?


Dome light stays on

Coincidence. The door ajar switch and door lock assembly are connected. The dome light is staying on because it thinks the door is still open(ajar). This may also be why the keythob doesn’t feel like working.

Dec 172017
 

2006 Cadillac CTS

Location of the TCM. Does a used one from another CTS need to be reprogrammed?
Does this this cause a engine reduce power message?


The engine reduce power message has to do with the TAC system. Throttle Actuator Control(TAC) is your electronically controlled throttle. In most cases the the throttle body(TAC System) will need to be replaced. In some cases a software update may cure the issue. And in rare occasions simply unplugging the battery for a few minutes works.

For whatever reason you want to swap out the TCM with a used one, you may need to reprogram it.

Transmission Control Module(TCM)

TCM(8) is located at the right front of engine compartment.

TCM location - 2006 Cadillac CTS

Transmission Control Module Programming and Setup

The transmission control module (TCM) must be programmed with the proper software/calibrations. Ensure that the following conditions exist in order to prepare for TCM programming:
– The battery is fully charged.
– The ignition switch is in the RUN position.
– The Techline equipment cable connection at the data link connector (DLC) is secure.
Program the TCM using the latest software matching the vehicle.
If the TCM fails to program, proceed as follows:
Ensure that the TCM connection is OK.
Inspect the Techline equipment for the latest software version.
Attempt to program the TCM. If the TCM still cannot be programmed properly, replace the TCM.

Dec 162017
 

2002 Ford Mondeo

Hi, my car won’t move in drive


Car won’t move in drive

First thing to check would be the transmission fluid level. If it is low, top it off and test. If it is not low, look at the color against a white paper towel. If the color looks dark or burnt then there may be internal damage. If the fluid level is full and the color is pretty pink, there may be a sticking solenoid in the transmission.

Of course there may be other things that could cause this such as a broken cv axle shaft but that isn’t very common. Another cause could be the shifter isn’t going into gear all the way. Try moving the the shifter to low and see if it will do anything. Does it move in reverse?