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Saturday, August 14, 2010

How To Bleed Air From Power Steering System

Just like the brakes, a power steering system must be bled anytime you open the system to replace a PS pump, hose or rack.  After bleeding the PS system on my 2002 Kia Optima, I recommend the following bleeding protocol suggested by GM.

BLEEDING THE POWER STEERING
Aerated fluid will result in noise from the power steering pump. The system should be bled any time a power steering component has been replaced, a fluid line disconnected, or for moaning and groaning noises. To bleed the power steering system, most technicians just fill the reservoir and turn the wheel from lock to lock. This is not the way GM recommends bleeding their system. Prior to bleeding the system, perform a visual inspection to be certain the hoses are not touching any part of the frame or body which can promote a noise. Make certain all hoses are tight, as a loose connection can allow air to enter the system even though fluid will not leak from the connection.

GM’s Recommended Bleeding Procedure:
1) Ignition switch off.
2) Turn steering wheel full left.
3) Fill fluid reservoir to Full Cold level. Leave
cap off.
4) Raise front wheels off ground.
5) With assistant checking fluid level and
condition, turn steering wheel lock to lock
at least 20 times. Engine remains off.
a) On systems with long return lines or
fluid coolers, turn steering wheel lock
to lock at least 40 times.
b) Trapped air may cause fluid to
overflow. Thoroughly clean any
spilled fluid to allow for leak check.
c) Keep fluid level at Full Cold.
6) While turning wheel, check fluid
constantly.
a) No bubbles are allowed.
b) If bubbles appear, recheck connections.
Repeat step 5.
7) Start engine. With engine idling, maintain
fluid level. Reinstall cap.
8) Return wheels to center position. Lower
front wheels to ground.
9) Keep engine running for two minutes.
10) Turn steering wheel in both directions.
Verify:
a) Smooth power assist
b) Noiseless operation
c) Proper fluid level
d) No leaks
e) No bubbles, foam or fluid
discoloration
11) If all conditions apply, procedure is
complete.
12) If any problems remain, see “Special
Conditions.”
Special Conditions:
1) Foam or bubbles in fluid: Fluid must be
completely free of bubbles. In step 5, be alert
to periodic bubbles that could indicate a
loose connection or leaky O-ring seal.
2) Discolored fluid: Fluid which is milky or tan
in color is an indication of aerated fluid.
Switch ignition off. Wait two minutes and
recheck hose connections. Repeat steps 7-
10. If condition still exists, replace O-ring
seals and clamps. Fill system and repeat
bleed procedure.
3) Pump whine or groan: With the engine running,
recheck hoses for possible contact with
frame, body panels or engine. If no contact is
found, allow fluid to cool down and repressurize
system.
If noise persists, remove and replace the power
steering pump. Repeat the bleeding procedure
following the pump replacement.
Following the procedures illustrated can save you
much frustration and your customer money, plus
you fix the problem the first time around. This keeps
the customer happy and coming back for more
service. A happy customer tells his friends about
your shop and that keeps the bays filled.

Kia Optima, Engine Tapping Sound

Recently, I did work on the power steering system of my 2002 Kia Optima.  Because I work many hours, it took me a few weeks to complete.  During this time, the car was cranked only briefly a few times.  Most of the time, it sat in my garage without being cranked.

When I finally cranked the car, there was a loud tapping sound coming from the top of the engine.  Since I had not done any recent work on the engine itself, I realized that this probably had to do with the car sitting still for so many days.

Someone suggested to me that I do an oil change with a new filter because the filter could be disallowing the proper oil pressure.  So I changed the oil and filter.  I then cranked the car and the tapping sound was still there.

Another person suggested that the valves were not being "pumped up" adequately.  He suggested that if I allow the car to idle for about 20 minutes, the valve might pump up and the noise would cease.  So, I allowed the car to idle for about 25 minutes.  When I returned to check on the car, the noise was almost gone.  I turned the car off and let it sit for about 10 minutes.  I then cranked the car and I did not hear the noise.

I drove the car a few miles yesterday and today and the tapping sound seems to be gone.  So, if this happens to you, before you freak out, do what I did and...

  1. Do an oil change with a new filter
  2. Allow your car to idle for 20 minutes at a time
  3. Make a note if the noise increases or decreases
I did not get around to it, but if this were to happen again, I would probably add some "Sea Foam" lubricant to the crank case for good measure.

I hope I have helped you.

Code P0123 & Slipping Transmission

2002 Kia Optima
2.7 L V6 Engine, Automatic Transmission
189,000 miles

Rough Idle and a Code P0123

Recently, I noticed the check engine light (SES light) come on.  I pulled out my OBD II code reader and hooked it up under the dash.  The code which returned was P0123.  I thought that it might be a fluke as some codes will set once and never set again.  So, I cleared the code and went about my business.  But, I did notice rough idle in the car and the light came back the next time I drove the car. I used the code reader to check the code again.  P0123 was back. Now, I was certain that there was something to the code P0123 so I looked it up to see what it indicates.
Code P0123 is triggered when the voltage output from the Throttle/Pedal Position Sensor/Switch to the PCM is too high.

The Throttle Position Sensor is located on the Throttle Body of the Intake Manifold and/or the Pedal Position Sensor/Switch is located on the Accelerator Pedal. These sensors provide precise input from the driver's foot in terms of how much power is needed—and how urgently—from the engine.

As the Throttle Position Sensor is rotated from its base resting position to full acceleration, it sends a increasing voltage signal to the Power Control Module (Computer) This decreasing or increasing voltage signal is used by the PCM to manage the Air Fuel Ratio and Spark Timing of the engine as well as other emissions system components.
I immediately did some research on the internet to double check why a P0123 code is generated.  Many people suggested that the TPS does sometimes die and cause bad idle.  Others suggested a P0123 can be thrown when something else is the cause, such as a bad MAP sensor.  The part costs approx. $50 so I didn't want to just buy a new one if it wasn't bad.  So, I decided to think about the problem for a day or so before deciding how to proceed.

Can a slipping transmission really be caused by a bad Throttle Position Sensor?

The next day, something interesting happened.  As I drove away from my home in the morning, the automatic transmission slipped out of gear.  It also did not seem to want to change to the next gear.  It was driving terrible.  "Oh great!" I thought to myself.  In addition to this P0123 code, I now have a transmission which is going bad......  and then it hit me.  Maybe the P0123 code and the slipping transmission were related somehow.  Could the source of the P0123 be causing the transmission to slip?

Backyard Mechanics + Google = Best Friends

I did a search on the internet for "P0123 slipping transmission"  I read a great deal and found that others did also have a code P0123 and a slipping transmission. Queue the light bulb above my head.  I was now convinced the two were related.  The question remained, was the TPS actually bad or was there something else going on which was causing the code P0123?  Could a bad TPS actually cause the transmission to slip?  The answer to the second question is, "yes", a bad TPS can cause the transmission to slip.  The transmission depends on the signal from the TPS in order to know when to shift and how soon, etc.  If the TPS is sending errant or no data to the computer then the computer cannot tell the transmission how to shift properly. Remember, modern cars are run by computer.  If the computer receives incorrect input from an inexpensive little sensor, then the car can run very rough indeed.

A Bit of Good Fortune

When I bought this 2002 Kia Optima used in 2008, I had removed the engine and installed a new one.  I kept the old engine for parts and still have it to this day.  Being a man who hates to waste money, I began to wonder if it was it possible that the old engine in my garage had a TPS still connected to it.  I hurried to my garage and uncovered the engine.  To my glee, there was a TPS still on the old engine.  I then took that TPS off and replaced the seemingly defective one on my car with this new found one.  I then cranked the car and drove it about 3 miles.

Photos of a TPS off of a 2002 Kia Optima V6


A Happy Ending

Victory is such a sweet joy, especially when faced with a potential $1000 repair of a transmission.  To my delight, the test drive revealed that the transmission slipping had ceased and the code P0123 was gone.  The rough idle had also improved.  Darn if that tiny little Throttle Position Sensor wasn't the source of the slipping.  I realize I need a longer, more in depth test drive to be sure,  but I am firmly convinced that the P0123 code was due to a faulty TPS sensor.

In Conclusion

So, if you own a 2002 Kia Optima, or any car for that matter which has the following symptoms;
  1. Check engine light showing code P0123
  2. A transmission which is slipping and which began this behavior about the time the P0123 code first showed up
.... then you likely have a bad Throttle Position Sensor (TPS).  Don't take your car to the dealer or a transmission shop.  Instead, get a TPS from a junkyard or buy one new.  It is likely that replacing your TPS will fix your slipping transmission and save you a load of money and frustration.  It sure fixed mine.

Friday, August 13, 2010

Servicing the power steering system (pump, pressure hose, return hose) on a 2002 Kia Optima V6

When I noticed fluid leaking out of the top power steering hose, I had no idea how difficult servicing the power steering system on my 2002 Kia Optima was going to be.  It seemed fairly straight forward at first glance so I decided I would save some money and do the repair myself.  But, as I am finding out, servicing a Kia Optima is not usually an easy thing to do.

The first problem was that the top "pressure hose" was leaking.  I drove around for a few months with this leaking because the Kia Dealership wanted $149.00 for this hose.  I thought I would come across a cheaper one but I never did.  It seems that Kia keeps a tight grip on its parts and who sells them.  During this time, the bottom hose sprung a leak too.  What luck I was having. Ultimately I had to buy the parts at a high price from the Kia dealership.  This inability to find parts anywhere other than the dealer was my first clue that I was in for a tough time.

So, I ordered the parts at the Kia dealership.  They screwed up and ordered the wrong parts for a 4 cylinder instead of the V6 even though I made it a point to tell them TWICE that I had a V6.  Ugggghhh! So I had to wait an extra 2 days.  Rather, my wife had to bum a ride for an extra two days because of their stupidity at Kia.

Then, when the parts came in, the dealership told me I needed PSF 4 fluid for the power steering system even though I later found that PSF III is recommended for the 2002 Kia Optima.  Not a big deal right?  Wrong.  The PSF 4 is ONLY available at Kia and it cost $19.00 per quart!  I needed two quarts.  Later, I went back to get a third quart of PSF 4 fluid from the dealership and they told me they were out of it until the following week.  The guy behind the counter could tell I was visibly frustrated and he suggested to me that I could use PSF III.  Evidently, Valvoline makes a good PSF III fluid and it is only $5.00 per quart at Advance Auto.  Again, the Valvoline PSF was recommended directly by the Kia dealership.  So, I picked up a few quarts and decided to flush the old PSF 4 out of the system and use the Valvoline.

I purchased a used pump and installed it in place of the original pump.  The original pump was probably fine, but it was noisy.  I didn't realize at the time that air in the PS lines caused the pump to make a lot of noise.  If I had used the original pump, I believe it would have been fine once I got the air out of the system.  But, alas, I did install the new pump.  It was not difficult to do.  Only 2 bolts hold the pump to the engine.  You have to remove two 12mm bolts which hold the intake line to the pump.  There is also a matter of removing the pulley.  I kept it on, but others might want to remove it before removing the pump.  It is fairly easy to remove the pulley.

So, with the new pump in place, I replaced the upper "Pressure" hose and the lower "Return" hose on the Kia Optima.  I do not exaggerate when I say it was a royal pain in the rear-end.  I had so much trouble getting my tools on the various hold-down screws.  But, the worst part were the flare-end connections where the hoses connect to the steering rack.  I used a flare end wrench, but there was so little room, I could only turn the wrench about 20 degrees before I had to readjust the position of the wrench.  It took forever.

Getting the hoses off seemed difficult enough, but putting the new ones on proved to be an exercise in patience.  Again, there is so little room where these hoses go that it is nearly impossible to get the hoses exactly where they need to be.  I strongly recommend you get a second person to help you put the hoses back on.  Working by myself, it took me about 3 hours to get the hoses in position.  Later, I would need to remove them and reinstall them and I had to go through the entire difficult process again.  I was not a happy camper.

Once I had the hoses hooked up, it was time to bleed the power steering system to get the air out of the lines.  Anytime you crack open any portion of a PS system, whether it is a hose, the pump or the steering rack itself, the system must be bled of air.  Bleeding the system was a very difficult thing to do on the Kia Optima.  Though it takes only an hour or so on most cars, it took me several days to get it done right.  No matter how much I bled the system, I kept finding air in bubbles in the reservoir. I eventually had to remove the hoses and reinstall them because I suspected I was leaking air into the system.  It was a nightmare.

Anyway, the Kia manual says the proper way to bleed a system is to jack both sides of the front end and put the car on jackstands so the tires are off the ground.  This will make it easier to turn the wheels from side to side.  And that is just what you do.  With the reservoir filled with PS fluid to the minimum to full lines, and with the car off, turn the wheels side to side a total of 40 times.  A turn to the left is 1 time.  A turn to the right is 1 time, etc.  AGAIN, DO NOT CRANK THE CAR DURING THE BLEEDING PROCESS.  YOU DON'T WANT TO CRANK THE CAR UNTIL ALL THE AIR IS OUT OF THE SYSTEM.  AIR CAUSES FRICTION IN THE RACK AND PUMP AND CAN CAUSE DAMAGE IF YOU CRANK THE CAR WITH AIR STILL IN THE SYSTEM.

Stop every 10 times or so and check the fluid level in the reservoir.  The fluid level may drop, just make sure it does not drop too low.  If it gets too low, air will get sucked into the system and you will need to repeat the procedure.

So, 40 turns, left AND right, all the way to the locks.  Checking every 10 times or so to make sure the fluid level is not too low.  After 40 times, check the reservoir for fluid bubbles.  Actually, it is best to have a friend turn the wheel while you watch the reservoir.  If you see medium to large air bubbles coming in from the return line (front of reservoir) then there is air in the system.  If you continue to see bubbles, let the car rest for about 20-30 minutes and then repeat the 40 turns again.  Do this procedure until no bubbles are present.  If you can't seem to get the bubbles out, check your connections on your hoses and make sure they are tight.  Torque down the pump bolts to their proper ft lbs.  Then continue on with the bleeding process.  Sometimes, the bleeding process will take several hours of this procedure.  In my case, I could not get the air out of the system for days.  I bought a hand vacuum pump to assist me.  I place the pump over the top of the reservoir and kept 20 hg of vacuum.  I did this for about 5-10 minutes at a time and then I would wait 10 minutes. I could see the bubbles leaving the system through the clear vacuum tubing. I did this for about 2-3 hours in addition to the right to left turns of the wheel which I had done earlier.  After I was satisfied the bubbles had diminished greatly (the vacuum pump will suck in some air into the reservoir and cause you to think there is still air in the system), I then cranked the car and checked the operation of the PS system.  The pump sounded quiet.  A noisy pump indicates air.  I had succeeded because no noise indicates no air.  It took me several days and a lot of patience, but finally, the nightmare was over.

To summarize, I suggest you consider your skills and patience before undertaking work on the Kia Optima power steering system.  Though I consider myself a slightly above average backyard mechanic, this job was very difficult for me.  Good luck.