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Weak Springs Cause Power Steering Problems

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Greg Stirling
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Weak Springs Cause Power Steering Problems
Greg Stirling   8/15/2011 2:06:21 PM
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Problems like this seem to permeate the manufacturing industry.  A company saving a few cents or dollars on a substandard cost reduced component which affects the function of the whole system - in this case a car.  I am sure whoever buys this car would be happy to spend another $2.00 to have one that is reliable.

There is a commodity in design engineering I call CS.  Collectivly, some companies have it and some don't.  Some engineers have it but management won't listen. Some companies have it, but have to hire outside contractors to provide CS.

By the way, CS = Common Sense

TJ McDermott
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Blogger
Re: Weak Springs Cause Power Steering Problems
TJ McDermott   8/15/2011 10:08:08 PM
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We have ourselves to blame for this race to the bottom.  The big-box business model is the lowest cost products, regardless of quality or service provided.  The big-box business model is SUCCESSFUL; how many independent, local, small-town hardware stores are still around?  The small town hardware stores arguably had better, personal service, might have had higher quality products, but the cost was higher as well.

Airlines have raced each other to the bottom as well.  There's not a single airline that offers a hot meal as part of the ticket anymore.  Most don't even offer hot meals!  Quality of service was sacrificed at the altar of low cost.

Many people will claim they will pay higher prices for better quality, but the market proves this is not the case.

Sport
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Silver
Re: Weak Springs Cause Power Steering Problems
Sport   8/16/2011 10:45:31 AM
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Inferior quality is one issue.  Even worse is Chevy's apparant willingness to deny the problem and take care of their customers.  This is one reason so many of their customers now buy Toyotas.  I'm sure it's expensive to correct this problem.  I'm inclined to think that they have gambled that it's cheaper to loose customers and or fight it in court when the time comes.

As it happens, I'm in the market for a new vehicle.  I was considering a new small Chevy as a town car.  This article has convinced me that this is a bad idea.

Beth Stackpole
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Blogger
Re: Weak Springs Cause Power Steering Problems
Beth Stackpole   8/16/2011 7:49:50 AM
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@Greg Stirling: Tempering the almighty drive to roll out low-cost products with CS engineering expertise is definitely becoming a difficult balancing act for many engineering organizations. Mr. Horton is lucky that his background and skill set let him attack the steering problems head-on--most average car buyers are not as fortunate. I say take to the Twittersphere and spread the tale of caution and the potential fix--I'd be hardpressed to think Chevy won't be listening!

Bill G
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Silver
Re: Weak Springs Cause Power Steering Problems
Bill G   8/16/2011 11:05:00 AM
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Amazing stories.  When I heard of electric power assist years ago, I thought "great idea - no more fluid leaks, hoses, engine-driven belts", but looks like the implementation fell short.  I second the brushless DC motors idea.  Seems wise for a motor in continual use where brushes would wear significantly, though costs are higher.

Where do they come up with $3500 for a replacement assembly, and no individual parts sold?  Can GM spell "extortion"?  Do you think their field testing predicted brushes would fail every 45K miles?  I drive several 60's cars and parts are so cheap I keep a backup for most everything on the shelf.

Re safety, I assume they designed the electric assist with something like an over-running clutch or slip clutch (aka garage door opener).  Otherwise, a jammed motor or gear could lock up the steering, which is the worst thing.  Even if one only loses the assist, that is enough to cause some people to scream and just let go of the wheel (my wife).  In traditional hydraulic systems, that happens whenever the engine cuts off, whereas electric assist continues as long as the battery is good, which seems more reliable.

I lost the assist in a hydraulic system recently when the plastic pulley cracked, which also drained the battery (alternator slipped on serpentine belt).  I only noticed when I exited the freeway, with strong effort on the wheel.  The problem is you only notice the lost assist when you need it most.

philipp10
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Gold
Electric power assist is scary
philipp10   8/16/2011 9:53:29 AM
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The idea of electric assist power steering is scary to me.  Last week, the battery on my RAV4 lost one cell.  My wife called and I gave her a jump.  I then drove the car to work, planning on replacing the battery after work.  What I found was, as long as the revs on the engine were up, all was fine.  However, at one point, as I was exiting the freeway, the revs dropped and apparently the voltage to the power steering dropped. When the power steering kicked out, I almost ran off the exit ramp.  Very dangerous. This will at some point cause a serious accident.

DougM21
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Silver
Re: Weak Springs Cause Power Steering Problems
DougM21   8/16/2011 10:06:37 AM
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There is another possible reason the original brush springs were low tension.  The following is speculation--I have no direct involvement with the electric power steering on this car.  Steering systems are very sensitive to friction, even small amounts of friction can make steering unpleasant--for example, not return promptly to center when released.  Adding a gear drive and motor to the steering column adds new sources of friction/stiction in the most sensitive place--close to the steering wheel.  I'll speculate that an attempt (perhaps misguided, in terms of the service history) was made to reduce the motor brush friction to the bare minimum in an effort to control the overall system friction. 

If friction was an original engineering concern, perhaps a brushless motor, and/or a direct drive motor (low RPM torque motor) would have been a better solution?

 

OLD_CURMUDGEON
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Platinum
Weak Springs Cause Power Steering Problems, etal!
OLD_CURMUDGEON   8/16/2011 10:20:10 AM
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While almost every article that appears in this column relates to poor "engineering", I would suggest that MORE people who experience these situations take the time to contact the various gov't oversite agencies to formally complain.  That is the ONLY way that manufacturers and/or distributors are going to get the message.  This is especially true for the automotive industry.  This article is a prime example for such an occurrence.  The family involved should have NOT wasted their efforts to contact CHEVROLET, instead they should have contacted the NHTSA, highlighted all the facts, and then waited for a response.  IF, in fact, an internet search showed several thousand entries from other owners experiencing the same malfunction, that would have been sufficient "ammunition" to generate interest at the agency.  Contacting Consumer Protection Agencies in local state gov'ts may also offer some relief, since the dealership which sold the vehicle may have to answer to a gov't agent, a burden they'd rather avoid!

 

rcwithlime
User Rank
Silver
Interesting comment. Makes me wonder...
rcwithlime   3/13/2012 10:27:02 AM
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In the past I have tried contacting Govt. agencies for defective products as well as services not provided. I have yet to receive any response worthy of my time. Maybe by contacting the NHTSA, I would have received a different response. I will have to keep on fighting the fight.

Without going into long details, I have only received the fast shuffle, and responses "We do admit that you have sufficient evidence to support your position, but we are unable to enforce. We suggest you contact legal representation and proceed accordingly."

After a while, you get most frustrated at banging your head against the wall and hoping that powers in place, (who are paid to watch over our individual interests),  will do their job, but then refuse to assist.

I guess we all lose if we give up the fight.

Thank you for your posting!

rcwithlime
User Rank
Silver
Update to this issue
rcwithlime   3/13/2012 10:39:39 AM
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As recent as last week, we received another notice from GM to have the power steering motor replaced. Amazing how just the motor was not available until GM had to issue a recall. Prior to that, the complete steering assembly needed to be replaced. But once the repair bill was on GM's $, they then (and only then) acknowledged that the issue was due to a defect in the DC motor. NO mention of the complete steering assembly, or reimbursement for those who already paid for the entire assembly replacement. No acknowledgement that they had erred previously when they advised that the entire unit needed to be replaced.

This was one of the main reasons the GM bailout was questioned. Naturally we all wanted to keep the jobs, but it defeated the natural course of  "supply and demand" that is reflected by quality of goods and value.

JG
User Rank
Iron
Weak springs
JG   8/16/2011 10:47:49 AM
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Where did this person do his research at?  The Cobalt has never made any recommended lists that I know of.  Did he forget GM went bankrupt.  Thank God, 180,000 trouble free miles ago, I bought a Honda.  If he had researched the Civic or Accord we would not be having this discussion.  Oh, by the way my Accord was build in Marysville Ohio. 

Charles Murray
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Blogger
Shameful response by Chevy dealerships
Charles Murray   8/16/2011 11:21:44 AM
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Compliments to Mr. Horton for tracking down the problem. Chevrolet's response, as explained here, is shameful, especially considering the potentially dangerous effects of this problem. I also agree with "Old Curmudgeon" below, who suggests that the victims of this kind of shoddy design should make a point of contacting appropriate government agencies.

Ratsky
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Platinum
Not a new issue...
Ratsky   8/16/2011 11:48:09 AM
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This kind of nonsense has been going on for a VERY long time.  For years, I had a strong preference for imports; however, every few years I would decide to give an American manufacturer a chance. In 1973, I bought my wife a Plymouth Scamp (P version of the Dodge Duster).   After a year or two, it began to have strange issues with the electrical system (short battery and light bulb life, intermittent operation of various subsystems, etc.)  After several trips to the dealer with no resolution, I found that the charging system wa the source of the problem.  It had an alternator, with a separate voltage regulator mounted on the firewall.  The firewall was painted, as was the VR box, and there was NO GROUND wire in the harness. To work, it required the ground connection to be provided by metallic contact between the VR box and the firewall/mounting bolt (ONE bolt, BTW!). As a cost reduction idea, they didn't use a star washer (or any other type of lock washer) under the bolt head.  Thus, after a while and miles accumlated, the VR lost its ground connection (intermittently, of course) and started WAY over-charging the battery!  I installed a star washer (OEM cost ~ 1/10 of a cent) under the head of the bolt, and had no more issues with THAT problem. I talked about this to a couple of co-workers who had owned other Chrysler products over the years (all EEs, of course) who told me that those cars ALWAYS had this kind of issue, it was well-known to Chrysler for years, but nobody would fix it! Unfortunately, this wasn't the only electrical issue; about 2 years later, we were driving down I95 in South Florida (worked for Motorola in Plantation then) when the car suffered a short in the wiring inside the steering column and caught fire!

Rob Spiegel
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Blogger
Re: Not a new issue...
Rob Spiegel   8/16/2011 11:50:19 AM
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Hey Ratsky,

I'd like to use this as a Made by Monkeys blog if you're willing.

Ratsky
User Rank
Platinum
Re: Not a new issue...
Ratsky   8/16/2011 12:14:37 PM
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 I have an even better one, much more recent: (it's always my WIFE'S car!) a 2006 Hyundai Sonata.  Shortly after we bought it (in July 2005, just after the new model came out early), I noticed a strange phenomenon: baout 50% of the time, the "Airbag disabled" tell-tale  would be lit when I was driving the car with my wife in the passenger seat.  Now, my wife is certainly larger than the children for whose benefit this new Federal requirement was ordained, and so  she brought back the car for warranty service.  They checked out the car, said they couldn't find any problem and couldn't reproduce it.  This was repeated a number of times.  Finally, being an EE working in the automotive industry, I got fed up with this lackadaisical response to a critical safety issue.  I downloaded a copy of the FMVSS (Federal Motor Vehicle Safety Standard) that applied to air bags and seats (all 500+ pages, BTW) and waded through it to find exactly what the requirements for this "safety" feature were.  It turns out that nowhere in this document was the intent of the requirement stated, nor were thee anything that I as an engineer could recognize as "real" specifications.  The only item I found was a TEST PROCEDURE for verifying compliance with the (otherwise unspecified) requirement!  It involved a couple of sandbags (one the wieght of the "average" child, the nother 150 lb. the represent a smallish adult), setting the front passenger seat fore-aft range to its center, and setting the seat back angle also to mid-range.  If the "child" sandbag was in the seat, the airbag should be disabled; if the "adult one was, then enabled. Apparently the unfortunate Hyundai engineers designed to the TEST, not the (unspecified) actual requirement, and set the seat micro parameters so that ONLY within a very small range centered on the seat position specified in the test would the airbag be ENABLED.  It gets better: finally, NTHSA ordered a full recall campaign from Hyundai.  We got the notice, and brought the car in.  The service manager explained that we would have to leave the car for several days; they had to remove the passenger seat assembly, and ship it to the srevice depot in California, where the ENTIRE SEAT COMPUTER assembly would be replaced.  They actually had no way to reflash the micro at all, much less than via the OBDII port!  They provided us a loaner (new Sonata); when we got the call that the car was fixed and ready, we went over and picked it up.  Now, the airbag is disabled only about 20% of the time.....

William K.
User Rank
Platinum
In response to Ratsky and the charging system problem
William K.   8/17/2011 12:45:52 PM
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It is not surprising that they went so very cheap as to use one bolt and no star washer. Having worked in the engine electrical department at Chrysler in that era, I can tell you that there was no concern for reliability after the first few years of vehicle ownership. A used car buyer was out of luck. A portion of this problem lay at the feet of the managers who all had cars that were maintained by inside mechanics on a daily basis, because nobody wanted to end their career by letting a boss-type experience an inconvenience with their vehicle. In addition, the purchasing department was rewarded for every cost reduction that they could come up with, which frequently included buying components that were less corrosion resistant than what the designing engineers had specified. So this was a case where the situation should really be labeled "managed by monkeys". since the assembly crew was not consulted about problems ever.

Rob Spiegel
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Blogger
Dissapointed with GM
Rob Spiegel   8/30/2011 10:08:27 AM
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Here's a comment from AndyG:

I continue to be disappointed with General Motors when it comes to design errors in safety critical systems.  I own a Cadillac Deville.  It is a 2001 model, so it has hydraulic power steering.  After all the years of cars having power steering, one would assume that technology had  been mastered, especially with GM's legacy "top of the line" automobiles.  The GM design on this car is such that if the engine stalls, the power steering not only goes away, but it immediately LOCKS the steering in the last commanded position.  I'm a strong guy and I couldn't steer the car when the engine died.  Before I could get the car into a repair garage to diagnose random engine sensor problems that caused a complete shutdown of the engine, the stalled engine and subsequent lock of power steering put me into the wrong lane more than once.  I was very lucky that I did not run over someone or hit cars in the other lane.  I would be very interested to hear an explanation why such a design was allowed to make it to production.

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