Page 59 – Sparky's Answers

2001 Chevrolet Silverado Ignition Lock Cylinder Will Not Turn

This 2001 Chevrolet Silverado came in with the complaint that the ignition key will not turn most of the time. I removed and inspected the lock cylinder and housing assemblies and found the fault with the tumbler assembly. The following are pictures of dis assembly.

Grasp the corner of the dash and pull out. Repeat pulling process across the dash.

Remove the screws from the bottom cover and pull the whole cover towards the seat and remove. Do not pull just on the bottom edge or you will break retainers. Work the whole panel loose top to bottom.

Remove the tilt wheel handle by wiggling and pulling straight out towards driver’s door

Remove screws from steering column cover, separate and remove.

Remove the steel knee bolster from under steering column. There are four nuts, two on each side.

Locate and separate the ignition switch junction block at left side of steering column.

Now go back to the lock cylinder and work the key until you finally get it switched on. Changing the position of the key in and out slightly while wiggling and rocking the switch will usually allow the key to turn on. It may take quite a bit of trying if the lock is in real bad shape. After the key is turned on, rotate it fully to the crank position and depress the retaining pin in the top of the assembly. With the pin pushed in pull the lock cylinder out.

Install new tumbler by inserting in the ignition housing and turn the key off. Reassemble and you are done.

I am going to do another post on how to code the new tumbler kit to your key.

Update July 11, 2011:
Well it was bound to happen, a bull in a china shop had difficulty reinstalling the lock cylinder and has now messed up his steering column. Wants to blame poor information from this site. I cannot stress enough that all of the work performed by me, on this site requires an extreme eye towards detail and a gentle touch. No part of this repair in particular should require any force or coercion of any kind!

Some extra things to keep in mind:
The new ignition switch needs to be indexed into the exact position, as the old switch was in, when it was removed. The ON position.
The key tumbler assembly needs to be checked, to make sure the locking bar drops flat and even towards the center of the tumbler assembly when the key is installed. If it does not, DO NOT INSTALL IT!
There is a retaining bar/panel that holds the springs in place for the individual tumblers. If it is not fully installed and flat, no protrusions past the outside edge of the tumbler housing, DO NOT INSTALL IT!

2001 Pontiac Grand Am, Codes P0105, P0172 and P0300

2001 Pontiac Grand Am with 2.4 liter engine was brought in with the SES light on and a complaint of tip in acceleration problem and rough idle. The codes that were stored were P0105 for a MAP sensor malfunction, P0172 for a system rich fault and P0300 for a general misfire fault. I opened the hood for a visual inspection and heard an unusual hissing sound. I followed it to a vacuum hose that ran from the intake to the MAP sensor. Removed the damaged hose and replaced with a new piece and problem is now gone.

The above picture is of course the bad hose and it is just normal wear and tear that caused this. Below is a picture of the MAP (sensor three wire connector) at top right of picture and the new vacuum hose (the second hose down from the connector)

The P0105 was obviously caused by the MAP sensor hose, the P0172 system rich was also caused by the faulty hose because the computer thought that the engine was running under a heavier load and the P0300 was caused by the unneeded rich condition (particularly at low rpm). I was especially happy that this was a simple fix as it is my daughters car!

2001 Mazda Tribute, Code P0300 and P0304

2001 Mazda Tribute with a 3.0 liter v6 engine Vin 1 and codes P0300 and P0304 stored. The P0304 code is very specific to cylinder #4 so that is where I started. After finding that cylinder #4 was one of the easiest to access I was quite happy. I first removed the coil cover on the front valve cover in order to gain access to the coils and spark plugs.

After the cover was removed I first pulled the #4 coil and inspected for problems. Number 4 is the cylinder to the extreme left of the picture.

When I removed the coil retaining bolt and pulled the coil I inspected for any signs of arcing which I found. The arcing was bad enough that it actually left marks inside the spark plug tube.

You can also see the arc marks on the spark plug boot near the bottom of the picture.

Easy enough but when I pulled the spark plug I knew I had more problems. A new plug and it was not properly gapped. Some one had tuned it up but done a poor job of it. Time to replace all of the spark plugs and boots and inspect for any damage along the way. The rear spark plugs require that the intake plenum be removed for access. I chose to only lift it out of the way as needed. The first thing that had to be done was to remove the egr valve from the plenum. I removed the two bolts and positioned it slightly out of the way. Next I removed the hold down bolts in the center of the plenum and lifted. Check for hoses, wiring and linkage that may restrict movement.

After lifting the plenum up I placed clean shop rags in the intake ports to prevent anything from falling in the engine. This is extremely important because if you drop something in the intake and cannot retrieve it, the engine will have to be disassembled or the engine will have catastrophic damage.

With the rags in place I could reach under the plenum and remove the coils and plugs. I inspected and wiped down the plenum gaskets, installed a new egr valve gasket and reassembled.

This is what I found in one of the back cylinders. The spark plug had not been properly tightened and combustion gases were leaking past the seal and causing what you see in the following picture. This is why I try to use a torque wrench on every spark plug I install. I also re click several times to make sure that the gasket is compressed properly.

Thankfully I had enough experience to know that I could have a problem with the coil on this cylinder and I reinstalled it in one of the front cylinders that are easy to access. Guess what I had a misfire in the new cylinder that I placed that coil in. Now it was easy because I had put it in an accessible cylinder. Tricks of the trade.

2001 Mazda Tribute,Code P0401 Stored

This Mazda had several problems, most of which were caused by previous work done to vehicle by others. The P0300 code is for random general misfires, P0304 is also for a misfire but is specific to cylinder #4 and P0401 is for insufficient EGR flow. I started with the easiest code which is the EGR code. The first step was to confirm that the EGR Valve was good. With the engine running, apply vacuum to the EGR vacuum port and see if the engine stalls or nearly stalls. It should. The EGR valve is the round object on the left hand side of the picture with the vacuum hose elbow on top. The engine did stall so that confirms that the EGR Valve will open and the ports are not restricted. If the valve had moved and held vacuum but not stalled or nearly stalled it would have indicated that the EGR ports were restricted and would have to be cleaned out. If the valve did not hold vacuum it would have indicated the valve itself was faulty. Not all valves operate in this manner so please follow guidelines for the vehicle on which you will be repairing. Some of the EGR Valves actually bleed off vacuum until sufficient back pressure is present in the exhaust. However in this case the valve was good and data on my scan tool indicated that the DPFE sensor reading was fixed. I disconnected the sensor leads and made sure there was a voltage change to near 5 volts and I jumped the signal wire to sensor ground wire to make sure the voltage went down to near 0 Volts in the data stream. This test can only be done if you have a scan tool that reads data and if you have access to wiring diagrams. The testing showed that the computer and wiring were okay. Diagnosis and replacement of faulty DPFE sensor. Later test driving confirmed the repair with voltage switching between .5 and 3 volts under fairly normal driving conditions. The DPFE sensor or Delta Pressure Feedback Exhaust Sensor is in the middle of the picture. One wiring harness and two rubber (actually high temp silicone) hoses attached. Most of you will notice that it looks like a Ford. That is because Mazda and Ford both use the same engine and controls on some of their models.

Way too many EGR valves are being replaced when the actual problem is a faulty DPFE sensor or restricted EGR ports. A little testing can save a lot of time and money.

I will get back to the misfire codes in another post.

Changing The Flasher On A 2003 Buick Century

2003 Buick Century with erratic turn signals. sometimes they work sometimes they don’t. A fuse cannot come and go so I decided to check the flasher. The flasher is located behind the left side of the dash.

Remove the fuse cover and then the lower dash cover and metal bracket in order to gain access.

The flasher is the lower part shown in the picture. This picture was taken from the right side of the steering column looking back towards the driver’s door.

The wiring harness tab has to be pushed in to release it from the retainer shown at the left of the flasher.

The relay has to be released from the mounting retainer.

1993 Mercury Grand Marquis,Wipers Do Not Park Properly

The wipers work fine except that they park with the wiper blades up, including while they are paused in delay mode. The problem is generally caused by a faulty mechanical park mechanism. and it has been my experience in the southeastern USA that leaves are the culprit. You will see in the following pictures. Let’s open it up and see.The wiper motor is located under the hood under a plastic cover. In order to gain access the wiper arms have to be removed. you have to lift the arms up off of the windshield about and inch or two and then slide the lock out and lift. There are pictures of the locks at the end of this article. Next the cowl covers have to be removed. They are attached with multiple screws and push clips. When the panels are loose you will have to remove the washer hoses from the rear of each panel. After those panels are out of the way you can release the tab locks and lift the cover out of the way.

This unfortunately is what you will probably see. Believe it or not I have seen a lot worse build up.

Armed with a shop vac start removing the debris so that you will be able to see all of the bolts holding the housing assembly down and so that the drains will be opened back up.

There are six bolts holding the housing down that have to be removed.

After the housing is loose you will need to remove the three bolts holding the motor to the housing.

The clip holding the linkage to the motor assembly has to be removed. Don’t loose this clip you have to have it to reassemble. Also Do Not let the linkage arm lay where it is in the picture. It got hooked under the edge of the glass and Sparky had to replace a windshield. Stuff happens, try not to let it happen to you. Disconnect the wiring. Use a small screwdriver to help release the clips.

Bolt the new motor in place and reconnect the harnesses.

When installed properly the arm should be position as illustrated in the following picture.

Reinstall the clip.

And put all of the panels back in place.

When removing the wiper arms the locks have to be released. Lift the arms away from the glass and slide the locking arms outward as shown in the following pictures.

1999 Pontiac Bonneville, Changing The Serpentine Belt

A customer friend called and asked if I knew a trick to changing the serpentine belt on his car. I told him to bring it by and we would look at it. The belt is inter weaved with the front engine mount and we found it requires removal of a spacer .

The spacer is located above and to the right of the crank sensor connection.

The bolt has to be removed and the sensor has to be disconnected. If only the nut comes off during removal. The stud has a hex or a torx end on it for removal of the stud.

After disconnecting the sensor and removing the stud the spacer will come out from the bottom.

When installing the spacer and stud, you have to line the mating edges as square as possible in order to slide the spacer into place. I also used a pry bar to slightly pull out the lower bracket arm.

Intermittent Starter Operation 2002 GMC Savana Van

This van came in with a complaint of the starter only clicks when trying to crank ,sometimes. In checking out the problem I noticed that when it did crank it cranked normally. I went to the starter and checked signals. The battery cable to the starter had 12 volts at all times, normal. The “S” terminal had 12 volts as I had someone try to crank the engine, normal. However the terminal connected to the starter motor lead was dead. Diagnosis of a faulty starter solenoid.
Whenever you have to do live testing (battery connected) be sure to be clear of all moving and potentially moving objects. Set the parking brake after making sure it works and chock the wheel if at all possible. Remember also the person helping you has to be some one you trust with your life and limbs. They are at risk!!!!!!!!!!!!!!!!!!!!

Starter removal requires that the battery be disconnected, the two starter wires have to be removed and the two mounting bolts have to be removed.
I started removing the starter and as soon as I got to the battery cable to solenoid connection I realized the nut was a little loose. I continued to removed the starter and I found that the cable had been loose for a while. You can see the arc mark on the terminal bolt below. Look at the left hand terminal bolt. The arc mark is at twelve o’clock.

You can see the arc marks on the cable terminal and the nut as well.

The customer did elect to replace the starter as well due to the mileage of the vehicle.

2002 Chevrolet Express Van Stoplights Inop / Erratic

Customer complaint of no stoplights or cruise control with park lights on.

This repair applies to both Chevrolet Express vans and GMC Savanah vans from 1996 thru at least 2002. For replacement sockets please visit The Electric Connection Online Store or contact us by email at info@the-electric-connection.com

The first picture shows the stoplight on without the park lights on.

The following picture is with the brake pedal still depressed and the park lights turned on. Notice how the illuminated portion of the light assembly moved from the bottom to the top. This is a classic faulty ground. In addition to both stoplights not working, while the park lights were on, the third or CHMSL (center high mounted stop light) bulbs were blown. Most cruise control systems, including this one, use the bleed through ground signal from the stoplight bulbs, when they are not in use, for an input signal to the cruise module. With the faulty ground, which was allowing current to flow through the stoplight bulb element from the park / tail lights, the module was mistakenly thinking that the brakes were being applied.

In order to perform this repair, first the upper cover has to be removed there are two screws to the outside edge and two nuts to the inside edge. After the upper cover is removed you can either depress the trim cover and remove the nuts behind the panel or as I prefer to do, remove the two push pin clips and then remove the nuts.

There are two nuts to the left side of the lamp assembly and one on the upper outside corner. After all three nuts are removed the assembly can be pulled out and flipped over to remove the stoplight socket.

Once the socket is removed, twist and pull the bulb so that the inside of the socket can be examined. You will find dark discoloration to the side of the socket that hold the black ground wire. It can be seen in the following picture just below the notch in the outside ground ring retainer.

Strip the tape away from the wiring and cut and splice one wire at a time to make sure that you do not cross the wiring.

It is also best to stagger the splice joints in order to maintain harness diameter.

It also makes a much better looking repair. Be sure to tape the harness back up and tape the harness to the side of the socket as it originally appeared.

The following pictures are from the other side of the van and as evidenced from the displaced solder, this was a crossed circuit and short just waiting to happen

2000 Maxima Blows The Tail Light Fuse

Boys and Girls this is why you do not install a higher rated fuse, jump a fuse with a piece of wire or wrap a fuse with tin foil. This vehicle had a very minor problem of the tail light fuse blowing and it escalated into a several thousand dollar repair because the owner or her friends tried 30 amp fuses where there was supposed to be a 10 amp fuse. When that was not working well enough they wrapped the fuse with tin foil. This car wound up with a burnt harness from the underhood fuse box around the firewall and back down the driver’s door sill. We lost some of the pictures but you can clearly see the damage in the wiring behind the driver’s kick panel.

The actual short was under the driver’s sill trim panel and probably would have been a two hundred dollar or less repair had it been left alone.

The only picture of the actual short was where the retaining clip had pierced the harness and melted . Sorry for not having more detailed pictures.