2003 Ford F150 , Idle Surges, Stalls, Multiple Lean Codes.

This 2003 Ford F150 came in with multiple complaints among which were a surging idle, stalling condition and the service engine soon light on. I did a quick check of the engine codes and found multiple lean codes.  I opened the hood with the engine running and could hear the familiar sound of sucking air. Fords for some reason are prone to developing vacuum leaks at the pcv valve hose, where it connects to the intake. In the following picture I am pointing to the hose connection that is leaking.

It took some effort and the use of long screwdrivers to force the rubber elbow of of the rear intake port.

With the hose removed it is easy to see the gaping hole in the rubber elbow.

The new hose is installed and I am pointing to the end that connects to the pcv valve. To install the hose, I routed the hose back into the original hoses position. Starting at the pcv valve area. I maneuvered the rubber elbow back into position at the intake port. Then I had to reach around both sides of the intake to get enough force on the hose for it to start onto the rear intake tube. Once it was lined up and slightly started I used a long hooked tool for more leverage in installing the hose elbow to the intake tube.

I then cleared the codes and started the engine. Took it for a test drive and monitored fuel trims. The fuel trims were normal and this one was done.

2002 Buick Century Left Rear Power Window Regulator Replacement

This 2002 Buick Century came in for a left rear power window regulator replacement. The customer was driving along and the window fell down. Pretty much a no brainer, the cable guides, on the power window regulator assembly broke.

The first step would be to remove the trim panel that covers the two attaching screws.

You can see that the retaining clips are in the center of the trim panel, in the next picture.

Again remove the two retaining screws, 10 mm heads.

Slide a tool under the front edge of the power window switch and depress the locking spring.

Lift the switch assembly up and out. Depress the latch and disconnect the wiring from the power window switch.

Using your fingers or a flat bar, plastic preferably, pry the interior door handle escutcheon plate away from the door panel.

Grip the lower edges of the door panel and pull the panel away from the door.

With the door panel removed, carefully pull the plastic moisture barrier away from the door.  I try to work from the bottom up so that the top seal stays in place.

Move the window glass around so that the mounting screws are accessible.

I use suction cup clamps to hold the glass in place so that I can continue to work on the regulator assembly. You may need the helping hands of a trusted assistant.

Depress the retainer for the harness connector and remove the wiring. From this point on it is basically nuts and bolts.

 

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The new regulator assembly should come at the correct preset level. This allows the regulator and motor assembly to first be installed into the door. Then the glass can be carefully lowered into its resting position on the regulator bracket. Install the bolts and start putting the whole thing back together.

2006 Infiniti G35, Power Seat Not Working

This 2006 Infiniti G35 came in with the complaint that the driver’s power seat would not move back to front. The customer had already had it checked and was told that the seat base would have to be replaced, $700 for the part plus labor. He asked me if I would take a look at it and see if it could be fixed any cheaper. Sure, I like knowing what is wrong with stuff anyways.

I did a little checking and found that the motor for the front/back operation was getting power and ground. It was also a little warm after testing. Seems stuck to me. I looked a little and it seemed to me that the drive mechanism would come off fairly easy. Three phillips head screws on each side holding the gear boxes in place.

I removed the screws from each side and then used a screwdriver to gently pry the gearboxes off of the seat tracks. The inner gearbox took a little bit more force.

As I separated the gear box housing, the first thing that I could see was the ball bearing assembly (outer race).

When the housing was fully removed, I could see the shaft, the gear and the bearing. I saw damage to the gear on the inner shaft. I wanted to check the track mechanism, so I used my cordless driver with a 10 mm socket to slowly turn the shaft. I had to switch between the inner and the outer shafts, to make sure the seat would move the full track length and do it smoothly. I did not want to install a new gear, only to have it strip out again.

To remove the gear, I first placed a ratcheting boxed end wrench on the shaft nut. Then I used a pair of smooth jaw pliers to hold the shaft extension. While I loosen the nut.

I used smooth jaw pliers because the shaft extension goes into a recess in the plastic gear box housing. I knew if I damaged that shaft it would probably destroy the housing in no time. Maybe, maybe not. Why take a chance anyway?

It surprised me that the old gear and sensor ring came off with relative ease.

I reused the sensor ring because the new gear does not come with that piece. It comes with a plain plastic spacer ring that would not have allowed the memory seat function to work. It would have, had to been disabled.

I installed the gear boxes and motor. Connected the wiring and was back in business.

The old and new gear pieces.

If you are going to do this job yourself, you need to realize that it is not a quick fix. It seems that there are three different gear possibilities and there is no rhyme or reason to which one may be in your seat. There may even be different gears on each side. The point is you will need to disassemble the parts to see which one that you have before you can order the parts. Also in some cases the memory seat feature will be lost and the system will need to be disabled. I have not had the opportunity to see how to disable this function yet.

2002 Oldsmobile Intrigue, No A/C Vent Control

This 2000 Oldsmobile Intrigue came in the complaint that the a/c vent positions could not be controlled. It would just blow out of every location a little, but no where with any force. This Olds Intrigue has auto a/c controls. It has an electric over vacuum control  system for operating the door positions. The first thing to do was to drop the hush panel, under the passenger side of the dash and check for vacuum supply to the reservoir. Vacuumed is supplied on the black hose, with the engine running of course. I found good engine vacuum at this location.

The next step involved locating the vacuum relay assembly. It too is under the passenger side of the dash. It is however closer to the right kick panel area, as shown below.

I think, there should have been two screws holding it in place but there was only one. A sign someone has tried to find the problem before me.

With the relay assembly hanging, I started the engine and held the unit in my hand. I then started moving the mode button to force the system to shift locations of the air flow. I backed this up by looking at scan data on my Tech 2,  to see if the control head was working correctly. All scan data seemed okay but I noticed that the relay assembly was chattering, instead of having distinct clicks. My years of experience told me that this was likely due to low voltage.

With a quick look at some wiring diagrams, I found that the relay assembly only had one power supply wire, Brown. With the ignition switched on, I found that there was only 6.68 volts present on the Brown wire.

In researching I determined that the brown wire was supplied voltage from the HVAC fuse, at position B2.

I checked voltage at the HVAC fuse and found it only slightly higher, 6.94 volts.

I also determined that the open leg of the fuse location marked as Low Blower was supplied power from the same source as the HVAC fuse. I connected a long test lead and fused jumper wire to the battery positive terminal, Then connected the other end to the open Low Blower fuse terminal. I did this with the ignition already on, so that the vehicles systems would not be confused by the signal. In fact the engine was running. When the power was supplied, the voltage as expected came up to battery voltage and the vent controls started working properly.

Time to replace the ignition switch. I am not including all of the details of replacing the ignition switch, as that information can be found in other posts and service manuals. I am including some relevant pictures for what is distinct to this vehicle brand. The lower dash covers need to be removed. The radio needs to be removed (do not disconnect the radio wires unless you have the theft lock code) and the instrument cluster needs to be removed.

Notice the two 7 mm headed screws in the picture below. Both of these screws are used, along with one of the radio mounting screws, to hold the ignition switch bracket in place.

A view of the ignition switch from under the dash with the lower panels removed.

With the key switched on, the locking tab for the shift interlock cable has to be depressed, so that the cable can be pulled from the switch. Turn the ignition back to the off position before removing the electrical connectors. Be careful while trying to rotate and remove the ignition switch and bracket from the dash. It still has the anti theft sensor wires attached to it. It will cost another couple of hundred dollars to replace that, if you damage it. For those of you with scan tools make sure there are no anti theft codes in either the PCM or BCM before starting. If there are replace the lock cylinder kit ,as well as the ignition switch at the same time.

2003 Chevrolet Impala, Gauges and A/C Compressor Turn Off After 5-10 Miles of Driving

This 2003 Chevrolet Impala came in with the complaint that the dash gauges and a/c compressor turn off after 5-10 miles of driving. There were dozens of codes stored in multiple modules and I seem to remember a reference to low  voltage. I eventually wound up in “Engine Data 2” to find the data line for ignition 1 signal voltage. Started the engine and ran for a minute or two at the shop. The voltage looked okay, so I set off on a test drive.  As I drove the voltage signal started falling about a quarter of a volt per mile driven. Definitely a problem here but what was the cause. My first suspicion was a faulty ignition switch so I started wiggling the switch as I drove. It would change sometimes but not but not enough to be sure about anything.

I looked at the wiring diagrams when I got back to my shop to find a good spot to test the ignition 1 signal voltage. The easiest place appeared to be at the ABS/PCM fuse in the driver’s side interior fuse box.

I removed the 10 amp fuse and installed a fuse tap to use as a test point. With the fuse tap installed with two fuses, I maintained my factory connection in the fuse box, and added a convenient test lead. I connected my trusty Fluke meter. Connected the other lead to a known good ground at the parking brake assembly.

I set off on another test drive until I had the same data stream results. The voltage at the fuse however remained at battery voltage. The next step would be to test the voltage where it enters the PCM.  The PCM, in case you did not know is inside the air filter box. First the cross brace needed to be removed.

Then the air filter housing had to be unclipped and the hose removed from the throttle body, hoses, harnesses & etc. Then the two 8 mm headed bolts had to be loosened to separate the housings.

With the housings separated I could finally see the PCM.  I lifted the PCM up and carefully cut the wire ties that hold the gray covers to the wiring harness.

I then used a small screwdriver to release all of the locking tabs that hold the cover to the harness connector.

I located the pink wire in the  C2 harness connector at position #24. The only pink wire at the PCM by the way. I cut the wire and spliced in a good length of wire to use as a test lead.

I reassembled the air filter box assembly and connected all hoses and sensor connectors. I switched on the ignition and checked the voltage.

I also checked the ignition 1 signal voltage with my Tech 2 scan tool.  There was a .2 volt difference. Nothing really to worry about.

I started the engine and checked the voltages again. Both had the same nominal running voltages. I took off on another test drive and monitored both voltage sources. The test lead voltage remained at 13.7 volts after an 8 mile test drive. The scan tool data voltage however dropped to under 9.5 volts. The gauges stopped working, the a/c compressor and scan tool dada stream also stopped, as it had in previous test drives.  I checked all other relevant scan data on subsequent test drives and noticed nothing else out of the ordinary. I checked the wiring diagrams to see how the grounds were wired and saw no way for the ignition 1 signal voltage to be affected by a faulty ground, without other controls being severely affected as well. My diagnosis was a faulty PCM. I acquired another PCM. Installed the correct operating system program and performed a theft relearn program as well. I test drove the vehicle again and all is well. The test lead voltage and the data stream voltage stayed consistently within .1 to .2 volts of actual battery voltage. Another one fixed.

2003 Chevrolet Suburban, No Blower Speeds 2 and 4

This  2003 Chevrolet Suburban came in with the complaint that the blower had lost speeds number 2 and 4. The customer was very concerned that the other speeds would soon fail too. This Chevy Suburban has manual HVAC controls so it uses a blower resistor assembly. Make sure the ignition remains off and remove the BLWR fuse from the underhood fuse box. This will ensure that there is no power on any wires while the work is being performed.  I do not recommend disconnecting the battery while this work is being done. Disconnecting the battery during the repair and then reconnecting it, will start the recalibration of the HVAC actuators. On older trucks you do not want to do this, unless absolutely necessary.

The blower resistor is located on the passenger side of the vehicle behind the glove box. There may be a  plastic cover or hush panel that has to be removed to gain access to the resistor and wiring. Normally only the far right and center screws need to be removed to drop the panel down enough to work.

After the cover is removed disconnect the harness connector and inspect for damage. On this particular vehicle the only terminals that were damaged were the third from the right, main ground and the third from the left, speed number 4. The burnt wire terminal on the purple wire is most likely why speed number 4 was not working. The heat damage to the black wire terminal meant that this Chevy was fixing to lose all blower speeds.

I have done a video on this this repair on a similar vehicle,as well. Please click here to view.

For more information on testing,  please click here.

2004 Chevrolet Tahoe Multiple Problems, No Communication

This 2004 Chevrolet Tahoe came in with a multitude of complaints. Some of the complaints were that it might not start, the power windows would stop working, the door locks would cycle, the radio would stop working, the instrument cluster gauges would stop working and  multiple warning lights would come on. From a technical perspective there would be an extreme amount of communication problems between modules. Also scan tools could not communicate with multiple modules. Maybe I just lucked out and had the vehicle cooperate but apparently several others had attempted to repair this Tahoe to no avail.   I had four different people talk to me about the problem for almost a month before it finally showed up at my shop.

I did not bother taking a bunch of pictures of scan tool data for several reasons. Number one there just would have been too many pictures of data screens. I also realized that they would only have meaning to technicians that have a Tech 2 or similar scan tool. They already know what the screens look like.

My diagnosis began with connecting the scan tool and pinging the modules to see how many were active. The first ping with everything working yielded 17 modules present. I took the time to write down each module. I then took the Tahoe for a test drive. The problems appeared driving around the parking lot. I pinged the modules again and only found 4 present. I eased the Tahoe back into the shop and parked it. I pinged the modules several times and wrote down the active modules. I cross checked the module lists and found that modules that are in or under the center console were consistently missing. A quick check with a mirror and flash light under the driver’s side leading edge of the center console and I was pretty sure I had found the problem.

The next step was to remove the center console assembly. The first thing that had to be done was to clean up the trash; cups, papers, french fries and chicken nuggets. That’s gonna cost em.  I then removed the front seats. Pretty easy. Two bolt and two nuts for each seat. It required moving the seats back and forth a little and disconnecting the harness connectors. The hardest thing is lifting the seat and rotating out of the vehicle without having the sharp edges on the seat track cut anything.  Both seats removed.  All of the trash vacuumed up. Time to work at the top of the console.

The upper trim panel pulls away from the center console. The lighter and power outlets have wiring that need to be disconnected.  The picture below shows the dash trim panel also removed but I do not remember if that is necessary or not. There are two 10 mm fasteners that have to be removed behind the console cover. You can see one in the picture below.

The insulation under my thumb is what I saw in the mirror that looked suspicious. It was pulled up and twisted under a metal bracket.

The light blue wire shown below was the actual problem. It is the Class 2 Serial Data line for the Rear Seat Audio controller, RSA for short. I only saw the RSA after pinging the modules one time. That was just after looking at the harness with a mirror.

The repair was simple. I wrapped the insulation scar with live rubber tape.

Wrapped the harness back together.

Put the harness protection material back into it’s intended position. It is not shown but I did wrap the abrasion protection material with tape and secured it to the black plastic floor bracket.

This bracket is where the wire was shorting out.

In the end, logical testing and a little bit of experience and this really was not too difficult of a problem. I have seen shorts in this general location before though.

Cliclick here to see another example.

2002 Buick Century No Low Blower Speeds

This 2002 Buick Century came in with the complaint that the lower blower speeds do not work. This Century has manual air conditioning controls. I have been down this road many times and it is just a faulty blower resistor. I will give actual testing information later, but for now I am just going to concentrate on changing the resistor.

First of all the blower resistor is located under the passenger side of the dash. There are a total of three push pins that need to be removed. Two along the leading edge.

One underneath, towards on the left side as shown below.

Once the panel is loose the courtesy light needs to be removed if present. A simple left turn and it comes right out. Remove the panel and position the light out of the way so that it will not burn you or anything else. If you are smarter than me, you will probably pull the fuse or bulb.

The blower resistor is located beyond the blower motor in the picture below. It has the seven wire, multicolored harness attached to it.

In the next picture I show the connector that goes to the blower motor. It has a locking tab that has to be depressed with a small screwdriver or other device. Then the connector can be wiggled out of the blower motor receptacle.

The seven wire connector has a latch on the outside of it, that has to be pulled slightly away from the resistor body, while the connector is pulled straight down. Tuck the harness out of the way while you continue to work.

Now using a 5.5 mm socket and ratchet, remove the leading screw from the blower resistor as shown below.

The next picture shows the removed screw, and the reason I make a point of showing it to you, is so you will have an idea of how much the screw would move with one full turn (the space between the threads).

Now bring the harness connector for the blower motor, that is attached to the blower resistor assembly, around the larger harness as shown below.

Now for something that is a bit unorthodox for me.  With your hand or a pair of pliers, pull the harness towards you, until the resistor pulls loose of the two front mounting screws. For many years I fought with sockets, swivels and extensions to try and remove the two front screws.

There are two slots for the forward mounting screws as shown in the picture below. Do not pull it with the intent of moving it a great distance. Just a firm pull to let it move about a quarter to a half an inch. If you pull too aggressively, you will wind up having to pull the broken pieces of the resistor board, out of the main a/c housing.

If you look closely you will see the two forward mounting screws.

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The new resistor on the left and of course the old resistor on the right. Notice that the interior resistor parts have been redesigned and are much heavier.

It is a little hard to see, but if you double click on the picture below you will see that I am using an open end wrench to slightly loosen the forward mounting screws. They only need to be loosened 1/4 to 1/2 of a turn. Doing this, while unorthodox, will allow the resistor just enough room to slide under the heads of the screws.

There should be just a slight bit of resistance as you push the resistor front edge under the two mounting screw heads. If it feels too easy, pull the resistor back out and tighten the screws slightly. If it seems like to much force will be needed, loosen the screws just a little bit more. It should feel like the detent when you close a tool box drawer. Now install the single screw closer to you and connect all of the wiring. When connecting the wiring, be sure to properly align the connectors and a straight and direct force to push it into place.  You want to avoid wiggling, while removing and installing these connectors.

If you need one of these resistors please click here. 

If you want to test the circuits coming in,  it will be as follows:

  • Terminal “A” Tan = Speed 2, power through blower switch from Low Blower fuse, 20 amp, Ignition
  • Terminal “B” Yellow = Speed 1, power through blower switch from Low Blower  fuse, 20 amp, Ignition
  • Terminal “C” Purple = Speed 4, power through blower switch from  Low Blower fuse, 20 amp, ignition
  • Terminal “D” Lt Blue = Speed 3, power through blower switch from  Low Blower fuse, 20 amp, Ignition
  • Terminal “E” Black = Blower system, ground at all times
  • Terminal “F”  Small Orange = Speed 5, power through blower switch from Low Blower fuse,  20 amp, Ignition
  • Terminal “G” Large Orange = Speed 5, Constant power from High Blower fuse, 30 amp, Battery

Fuses are located in the interior fuse boxes.

2000 Ford Taurus, A/C Not Working, Fuse #28 / #128 Blows

This 2000 Ford Taurus came in with the complaint that the a/c did not work. The customer had already figured out that the 15 amp fuse number 28 in the underhood fuse box was blown. It is worth noting that in the wiring diagrams that fuse is referred to as fuse number 128.

Power on one side.

No power on the other side. The fuse is blown.

The a/c compressor relay.

I installed a new fuse and unplugged the relay. Started the engine and turned the a/c on. I installed the relay and watched for the fuse to blow. Nothing happened. I checked the terminals at the relay socket and found that I did not have power there. Rechecked the fuse and it was blown. Did I not see or hear the fuse blow? Let’s try this again. Installed another new fuse. Checked to make sure that the fuse had power on both sides and that I had power at the relay socket. All was well. I started the engine and turned the a/c on. Before I installed the relay I wanted to confirm that there was still power at the relay socket. No power and the fuse was blown. Okay the compressor is not the culprit in this case. Time to look at the wiring diagrams.

The wiring diagrams showed that the oxygen sensor heater elements were connected to this fuse. I checked the wiring at the front O2 sensor and all was well. I went to check the rear O2 sensor wiring. Pretty hard to see, so I used a mirror. I found the O2 sensor connector laying on the EGR valve tube.

After some disassembly I got the connector out to be able to repair the problem. I had to install a new O2 sensor and a new harness connector.

I also investigated to find the reason for the connector laying on the hot EGR valve tube.  It seems as if someone had changed the DPFE sensor. They could not get one bolt undone. So they mounted it with one screw and rerouted the hoses going to the DPFE sensor. Well in doing all of this, the connector was forced off of its’s mounting location and fell on the hot EGR valve tube. I removed the screw using a pair is vise grip pliers to grab the stripped head. Properly mounted the DPFE senor and correctly routed the hoses. I then secured the O2 sensor sensor connector to it’s mounting clip.

Another one done. Sad that the whole thing could have been avoided with quality workmanship on the DPFE sensor replacement. In case you were wondering the DPFE stands for Delta Pressure Feedback Exhaust. It measures the pressure difference in the exhaust system at two different points. The sensor sends a voltage signal to the PCM. The PCM uses that signal to determine if the EGR valve responded to the PCM command to open. A malfunction usually results in a code P0401 insufficient EGR flow.

2002 GMC Sierra Blower Works Sometimes

This  2002 GMC Sierra came in with the complaint that the blower would work sometimes, but now, it would not work at all.  This truck has manual HVAC controls so it uses a blower resistor assembly. I do not recommend disconnecting the battery while this work is being done. Instead make sure the ignition remains off and remove the BLWR fuse from the underhood fuse box. This will ensure that there is no power on any wires while the work is being performed and it will prevent an unwanted recalibration of the HVAC actuators.

I recently completed a video of this repair on a similar vehicle. Please click here to view.

The blower resistor is located on the passenger side of the vehicle behind the glove box. There may be a  plastic cover or hush panel that has to be removed to gain access to the resistor and wiring. Normally only the far right and center screws need to be removed to drop the panel down enough to work.

After the cover is removed disconnect the harness connector and inspect for damage. On this particular vehicle the only terminals that were damaged were the third from the right and the third from the left. Sometimes all of the terminals will be damaged and the plug will be melted to the resistor as shown in later in this repair.

In the pictures below you will notice that the black wire has substantial heat damage. The black wire is the ground for the blower motor and the high blower relay that is within the blower resistor assembly. When this circuit is lost the blower motor will not function at all.

For more testing information, please see the repair post at this link.