2002 Chevrolet Impala 3.4 Cabin Air Filter Installation

Just a quick post for this month (I may post another one dealing with this same vehicle). This 2002 Chevy Impala 3.4 came into the shop for repairs. One of the things we checked for the customer was the fluids and filters. This is a pretty standard procedure (along with checking other basics as well).

We noticed that this vehicle was supposed to have a Cabin Air Cleaner in the HVAC system. The one for this vehicle was missing. Below is information showing how to know if the car should have one and where it is located.

First, the glove box must be opened.

If the vehicle comes from the factory equipped with a Cabin Air Cleaner, there should be a sticker (see below) in the glove box giving this information. In the case of this vehicle, the sticker was present. We proceeded to check to see if the filter was actually there; and, if so, if it needed to be replaced.

To gain access to the filter, simply push in on both sides of the glove box, until the tabs release (see below). There will be one on either side. Once these are pushed in the glove box will be able to drop down out of the way toward the floorboard.

Below is a picture of the glove box dropped down out of the way. This allows access to where the Cabin Air Cleaner "lives".

Next, the cover must be removed. It is simply a plastic cover with tabs holding it in place. The tabs, as seen in the picture below, are on the bottom of the cover.

Once the cover is remove, the area where the filter "lives" can be seen. As evidenced from the picture below, it is obvious there was no cabin air installed.

Below is a picture of the cabin air filter that was purchased to install.

Below is a picture of the filter installed.

From here, it is just an issue of reversing the steps and putting everything back together.

2004 Chevrolet Silverado 4.3, Left Side Marker/Turn Signal Bulb Replacement

(This is not a picture of the actual vehicle we worked on. This is a similar vehicle, a 2004 Silverado. The picture is from: http://www.edmunds.com/chevrolet/silverado-1500/2004/?sub=regular-cab.)

We did an oil service on a 2004 Chevrolet Silverado 4.3. As part of an oil service, we always do a safety inspection on the vehicle. The safety inspection consists of checking things like tire pressure, belts and hoses and the external lights, among other things.

As we checked this one, we found the left side marker/turn signal bulb was not lighting. Many have questions about how to change certain bulbs on vehicles. Some are easier than others. Here is how you change this one. 

First, we had to remove the headlamp assembly. To do this, we had to remove the holding pin. It simply slides out.

Once the pin is removed, the headlamp can be lifted up and moved out of the way. We did not disconnect the headlamp, we just simply moved it aside to gain access to the lower assembly.

Now that the headlamp assembly is moved, we can get to the lower assembly. There is a plastic tab that moved be pressed to snap the assembly out of the bracket, allowing it to be moved to get to the bulb. In the picture below, I am pointing to this plastic tab with my screwdriver.

Once the tab is pressed, gently pull forward on the assembly. Be careful as this is done, so as not to break the plastic tabs. The picture below shows the assembly moved out from the bracket.

Below is another picture of me pointing to this plastic tab, this time with the assembly removed. This gives a better view of the tab.

At this point, it is a matter of replacing the burnt bulb. A simple twist of the connector will free it from the housing, then pull the old bulb out and replace it with a new one. The next picture shows the bulb now illuminated.

We then put the connector back into the housing and snapped the assembly back in place.

When reinstalling the headlamp assembly, you must get the plastic tabs/line up pins in the proper slots. The picture below shows the two tabs on the bottom of the headlamp assembly.

Those two tabs go into two slots. The picture below shows the two slots.

Once these are lined up properly, the headlamp assembly will go back in place and the holding pin can be slid back into place.

Once everything was back together, we did a quick recheck to make sure the bulb was illuminating properly. 

2000 Chevrolet C3500 5.7, Wipers and AC Inoperative

This 2000 Chevrolet 3500 came into the shop with a couple of complaints by the customer. He said that a few days before both his AC and windshield wipers stopped operating.  He had checked a couple of fuses, but was unable to find a problem.

First things first, I confirmed the customer's concern.  The AC and the wipers were inoperable.  Next thing to do was to pull up a wiring diagram and start checking the circuit.

I first checked out the two fuses in the fuse block on the left-hand side of the dash.  The wiper and AC fuse are next to one another.  At first, I wondered if something might be going on with the terminals.  When I checked the fuses (Fuse 11 Wiper 25A and Fuse 12 HTR-AC 25A) with KOEO (Key On Engine Off) and the AC and wipers in the on position, I got ground.  No power was coming to the fuses.

Now that I knew there was no power to these two fuses, it was time to find out what their power source was.  Again, consulting the wiring diagram, I saw power was supplied to these circuits by the IGN B 50A fuse.  I saw the radio was also powered on this circuit, and when I checked the radio, as expected, it did not work either.  The IGN B 50A fuse is located in the Power Distribution Box under the hood, on the left (driver's) side of the engine compartment.

The fuse I'm pointing out is the IGN B fuse.  When I checked it with the Power Probe it showed one side with power and the other side without.  This meant we had a blown (melted) fuse.  I replaced the fuse, turned the key to KOEO and tried the problem circuits.  They all now worked.

Of course, fuses don't just blow for the fun of it.  When I reported my findings to the customer, telling him we would need to do further diagnostics to determine the cause of the blown fuse, he opted to pick it up and run it until he has any more trouble out of it.

I advised him on the potential problems and inconveniences that could result from this; but, he decided to pick the truck up as is anyway.

I just hope it doesn't decide to blow when it's raining!

2002 Chevrolet Cavalier 2.2, Engine Light on with a P0440 Code Stored

This 2002 Chevrolet Cavalier 2.2 came into the shop with a DTC P0440 Evap Emissions System Fault.  The first thing we did was to give a visual inspection of the EVAP system.

We did not see any obvious problems, such as, broken or disconnected hoses, unplugged components (i.e. purge or vent solenoid), broken wires, or loose/missing gas cap.

Many people, when presented with this code, will automatically replace the gas cap.  While these caps do need replacing from time to time for maintenance issues, this may not solve the problem.  In this case, the gas cap was not the issue.

We then decided to use our diagnostic tool and, using its bi-directional command capability, commanded the purge and vent solenoids on and off.  When we did, we heard (and could feel) each one turning on and off as we commanded it.  We did this several times to ensure there was not an intermittent problem with sticking in the solenoid.

Next, we connected our smoke machine, which we use to check for EVAP leaks.  Again, using the diagnostic tool, we commanded the vent solenoid on (which closes the valve . . . this valve is normally off and thus open, to do the test it must be "On", meaning the vent is closed, so as to allow the system to hold the smoke in), and tested the system with smoke.

The picture below shows the evidence.  It is a bit hard to see, so we have drawn an arrow to point to the evidence.  What we saw was smoke boiling out of the vent solenoid, even though we were commanding it "On", thus closing the vent.  Therefore, with the vent "On" no smoke should have been escaping.

With this evidence, we removed the vent solenoid.  What we found is that someone had tie-strapped the diaphragm.  More than likely, a previous owner (our customer said they had not done this) knew about the problem and tried to rig it to work.  Not a good idea.  The solenoid was actually leaking from around its diaphragm, so a new one was in order.  A picture of the old one, tie-strap still on is below.

The next picture shows the new vent solenoid in place.

  
Just FYI, there is a short wiring harness (see below) connected to the vent solenoid.  These are notorious for fraying and breaking, due to rear end movement.  Like the gas cap above, this was not the cause of this failure.  Silver bullet fixes usually end up costing a customer far more money than simply taking it in to a professional to have it properly diagnosed and repaired.

Here is the short wiring harness (I am pointing to it in the picture).

After completing the repair, we cleared the codes and data associated with it.  We then ran a EVAP system test with our smoke machine.  The test passed.  A picture of that is below.  You will notice the green lit LED indicating the test completed and passed.

There are many variables when it comes to diagnosing and repairing an EVAP system.  A basic understanding of how the EVAP system works on that particular make and model is essential.  A visual inspection is always the first place to start.

Don't jump at silver bullet fixes.  You may get lucky and it may be your problem and repair your vehicle.  Then again, you may spend quite a bit of money chasing several silver bullets and in the end be left with the original problem.

When in doubt, find a professional you can trust and take it to him/her and let them do the proper diagnostics and repairs.  It may end up saving you far more money in the long run.

I know the economy has been rough and times are tough.  But, throwing parts at a problem can compound that problem quickly.