Posts

Check Engine Light OBD II

Most of us know that, “BEEEEP” from your car, followed by that little amber light, that looks like an engine with a lightening bolt in it. Or maybe even the phrase, “Emissions Workshop” showing in the instrument cluster. But do you know what it means when your vehicles check engine light comes on? Understanding what your check engine light means can save both headache and wallet-ache! Before I get into what a check engine light means, let’s talk about what it is, and why we even have it.

All cars from model year 1996 and newer are set to a basic standard. That standard is known as O.B.D II, short for On Board diagnostic second generation. It basically says that all cars will meet a certain standard when it comes to diagnostics, they include

  • A standard connector to hook up a scan tool. This is so all shops can gather the same information.
  • Standard(ish) location for the connector, called a Data Link Connector or DLC for short
  • Standard codes, basically if a VW has a failed sensor, and a Honda has a failed sensor, they must use the same code to describe the fault, more on that later.
  • There are more standards, but they have to do with communication rates, and more things that do not really matter.
  • Also, the light itself has a standard(ish) look to it.

    VAS 5051B Volkswagen scan tool

    Here is the VAS 5051B hooked up to an EOS with a top issue

When your check engine light comes on, it means the cars engine computer sees an issue. The issue can be anything from a loose gas cap, to engine timing being wrong, or some crazy wiring issues. I could go on for days and days about all the ways that the check engine light can come on.

When you bring your car to have the codes checked, I would hook up a diagnostic tool. I generally prefer a VAS 5051B. That is the big boy of VW scan tools. I find it to be far more reliable than the other scan tools we have. The information that I get is show like this.

P0420, Catalyst efficiency below threshold.

The “P” code is used to determine what system the fault is. P0420, the P is for power train, the 0 means that a Fuel and Air Metering and Auxiliary Emission Controls fault exists, and the last 3 digits give a more specific system of failure.

Check engine Lights

Your check engine light might look like one of these

There are 3 states of your check engine light.

OFF
If your check engine light is “OFF”, you generally have nothing to worry about. There might be an issue, but it has not happened enough times to set the light. Most issues take 2 failures in a row to turn the light on.

ON
If the light is “ON”, you have an system in your engine or transmission that is having an issue. If your car is driving normal, get it to a service station when you can. I DO NOT recommend waiting for an extended period of time. The longer you wait, the more likely you are to have more issues.

FLASHING
Ok, this one is pretty serious, if the light is “FLASHING”, you need to STOP driving and have the car towed to a service station(I prefer the dealer of course). When the light is flashing, your vehicle is mis-firing. That means the air and fuel is not being used properly. This will cause damage to the vehicle emissions system, and that is expensive.

Some quick advise, if your check engine light comes on, check your gas cap first. It is free, and might eliminate the hassle of bringing your car in for service. Also, if your light is just “ON” and the car runs fine, don’t panic. Just get it fixed soon.

Don’t forget that we have are on facebook. Also, if you hate check engine lights, just click one of the share buttons below, it will eliminate them forever~well, not really but it is worth a shot right 😉

Cabrio top

As you guys know, I have been looking for a project Volkswagen. I have my eye set on a Cabrio/Cabriolet but people think they are worth about double what they are actually worth. I decided to open up my search to add a GTI in the mix. Well wouldn’t you know I was able to find a 1996 GTI on Craigslist. The ad was pretty good, and noted that there were some issues with the car, but what did I expect from a 16 year old car.

Cabrio top

This was my 1st project VW. I only paid $500 for this Cabrio. I sure do miss it.

All ready to buy this car, I made the 40 mile trek to check it out. When I got there, I knew almost instantly, this car was not what the ad said. I don’t

think that the kid selling it was being deceitful, but I know that he was not telling the whole story. I spent about 45 minutes picking the car apart. Everything from damage on all sides of the car, a very oblivious water leak, and every light in the dash lit, to no a/c system, and headlight wires just flopping around. Yep, it had NO headlights.

The sad part for him is I really know this car. I can spot something out of place pretty quickly. The more I looked at this car, the more I found wrong, and more I found wrong, the less I was willing to pay. It pretty much broke down like this.

  • He posted the ad for $3000
  • Next day he changed it to $2500
  • I noted ALL the issues and offered him an offer of $1500. It would have cost me a few hundred dollars to get it drivable.
  • We went back and forth, me being very firm on my offer, and could not come to a price

Now I am only a little bummed that I could not get this car. There are 2 things that really make me mad about it. The poor car was abused. I hate seeing an awesome car ruined like that. The more important issue is, he will sell that car, and get what he wants for it. To someone that doesn’t know this car inside and out, it will seem like a good deal. It looks a little rough, but it “runs good”.

I thought I would put together a list of things that must be checked when looking a buying a used car. This list will help you avoid a big problem. Just a couple of warnings. This list will not predict the future. There can be hidden things that you will not see. I recommend using this list to deciede if it is worth getting checked out by a professional. I ALWAYS ALWAYS ALWAYS, one more time, ALWAYS recommend getting it checked out by a mechanic, but more on that later

  • Do a walk around the outside, check for damage, and really look at the paint, even an untrained eye can spot color differences in paint.
  • Open the hood. Check the bolts that hold the hood and fenders on. Check to see if the paint is cracked. That means the bolts have been moved due to a repair.
  • Check ALL the fluids you can. On top of being clean, give it a good sniff. If it smells burnt, that is a no go
  • Check for fluid leaks. Most fluids will leave a trail the engine should not be wet with oil or coolant. Look at the fans, make sure they turn. PLEASE do this with the car off.
  • If you can see any electrical connectors, make sure they are not broken. Even if you don’t know what they are for, you know they should not be broken.
  • Wiggle stuff, Most car manufacturers do not let parts just flop around. Things are almost always secured in some way.
  • Check where the windshield and meets the cowl(that is where the wipers are) Bad seals there can cause a severe water leak.
  • Moving to the inside, open the door and take a big sniff. Water leaks have a very distinct smell. It kinda smells like a mildewy basement.
  • Look at the roof, see if there is any water staining around the windshield, windows, sunroof.
  • Touch the plastic of the interior. Lose trim can mean someone was “fixing” things
  • Look at the door jambs. Often side damage is not repaired as well on the jambs as it is on the outside
  • Open ALL the doors, make sure they open and close properly, and don’t over extend.
  • Open the trunk, check for the spare tire, and look for cracked paint on bolts, cracked seals, water
  • Check all the lights inside and out. Take a look at the tires, and brakes. I did a post about 5 quick car checks a while back, check it out for more information.

Since you will not be inspecting the car on a lift, there is no need to talk about the underside of the car. Leave that to a professional. Remember, before you buy a car, have it checked out by the DEALER! Yep, do not take it anywhere else. You might think that dealers are a rip off, but no one sees more of that specific car than a dealer mechanic. Now, if you make it this car, please take the mechanics advise. I have done used car inspections for customers, found a lot of issues, and people still buy the car. Then come back a few months later saying their car has all these problems. (D’oh)

Well, my search for a project VW continues. I will be sure to keep everyone posted about the search.

If you like this post, please feel free to share it by clicking your favorite button below! 🙂

I moved “Shop Shots” up to Wednesday this week. I will actually be out of town for a couple of days. I don’t think there will be a post Thursday or Friday. Make sure you check out the forum too. I know its called Technician DataBase, but its not just for techs. It is for everyone, customer, mechanic, enthusiast, we got some fun conversations happening over there! Go to Technician Database, and sign up, I will have to approve you so it might take a few hours to join. Also, be sure to post in the “First 50” thread, you will be locked in as a founding member, and I will be giving something cool away.


This is a picture that I took on Monday. I was doing a 20,000 mile service on a 2010 Jetta, and this caught my eye. The bolt was out about 1/4 of an inch. I checked the history to see if the shop had done any work in this area. The customer did have an alignment done, but that was at ~1300 miles. I wouldn’t think that it could be loose for that many miles. I am surprised that the customer didn’t notice a clunking due to the bolt being loose.

It actually brings up a good point. When something like this happens, what does a mechanic do? If I say something to the customer, we would get blamed for messing the car up. VW warranty would not pay to tighten a bolt. The best thing for everyone is for me just to fix it. Not really hide what I found, but it was not worth stirring up trouble over. I torqued the bolt, and went through the other bolts on the subframe just to make sure they were properly torqued. I didn’t get paid anything to do it, but I surely couldn’t let the car go with a loose bolt.

This is an axle from a 2005 Jetta. The outer joint to be exact. The boot was split, so I removed the axle to replace the boot. This is actually a really common repair. Something that I have done lots of times. A couple of whacks with a 3lb sledge hammer and the joint comes right off. This one however didn’t want to play nice. I tried for about 30 minutes to separate the joint from the axle shaft. I beat the out edge of the joint up pretty bad. I finally had to accept defeat and tell the customer they needed a new axle. It really sucks that the customer had to buy a new axle, but I really did everything I could.

Knowing that the customer had agreed to buy a new axle, I was totally determined to get he joint apart. I brought out the big guns. I used my air hammer, but all I did was break the joint more. Since I had to send the old part back, I figured it was better just to call it quits. I don’t like to lose!

This is a short video of a crazy instrument cluster. This Jetta had several water leaks. I never found any water in the cluster, but something really pissed it off. This might be one of the strangest acting clusters I have ever seen. Also if you don’t drive a VW, the buzz that this cluster is making sounds NOTHING like it should. I recommend watching this a few times. Watch how fast the 2 small gauges move. This car is actually still at my work. The customer fixed the issues, but they have not came to get it yet. I think we are going on 3 months. I am pretty sure it was towed in before Christmas.

I hope you guys have a really great weekend. I will be spending some time in the forum, so swing by and say hello! Also, if you want to connect with me, the 2 best ways are on Twitter, or just email me!

Every once in a while a car comes around that is sent straight from hell. The crazy problems that keep me awake at night. Things that, if you were a professional writer, you could not even make up. When this happens, having a game plan to crucial!

There are times when we(mechanics) just can’t figure out whats wrong with a car. When this happens we have to take things to the next level. Thankfully this is not something that happens a lot, but when it does, it can make for a bad day!

STEP 1 ~ Ask another mechanic
This is usually the first think that a mechanic does when they can’t figure out a problem. The guys working next to me are a HUGE resource of knowledge. The odds of them running having ran into a similar issue is pretty good.

The other good thing about asking the guy in the next bay is a totally different perspective. They come in with a fresh set of eyes. There comes a point when frustration starts to set in. Getting a fresh pair of eyes, and a fresh mind is always a good choice.

Step 2 ~ Take a break
You would think that this would be step 1, but it usually falls to number 2. If you have asked someone working next to you for help, and could not come to a conclusion, you are starting down an unhappy path. Much like asking someone else, taking a break will gives a chance to clear your head.

Walking away for a couple of minutes is a perfect way to think about the issue while not buried under it. If I smoked, this would be the perfect opportunity to burn one, then come back and reevaluate the problem

Step 3 ~ Computer Research
If you have not fixed a car by now, its time to break out the old repair manual. Depending on what the problem is, VW has several different resources available.

  1. Standard repair manual. ~ This is the (online) book that has information to fix our cars. It contains some information, tests to run on components, wiring diagrams, and some VERY basic how to’s
  2. Scan tools ~ Our scan tools does more than just tell us the faults stored in all the vehicle computers. They have software built in that adds different tests based on the faults. The tests are not the end all of solutions, but it can give some ideas on where to go next.
  3. Technical Service Bulletins(TSB) ~ This is a repair update that is issued by a manufacturer. It can be anything from a tip to fix a rattle, to tips on diagnosing transmissions. They are NOT recalls. Customers will not be notified about them. This is something a mechanic can use to help fix/diagnose a problem. This information is available to anyone that wants it.
  4. Tech Tips ~ This is something that VW issues to us mechanics. It is either the precursor to a TSB, or just a quick tip. Usually a very short blurb about a issue with a car.
  5. Google ~ If 1-4 do not work, Google can be a life saver. There are lots of really sharp people that have put great info on the web. I am not too proud to do a Google search 😉
Step 4 ~ Call in reinforcements
Now that you know your getting your butt kicked, its time to call in the big guns. VW has a program set up to help mechanics when they are stuck on a problem. Its called VW tech line. What we do is, send an email to our VW tech help line folks. We attach diagnostic logs, photos, videos(I have never attached a video), and answer several questions about the issue with the car.
After sending the email, we have to call the guys at tech line and talk to them. They usually ask the very simple stuff like “did you check the battery, did you check this, check that, is the car on fire?”. After the basics are covered, its time to get to business. They have access to all of the cases from VW. They can tell how many times someone has called tech line about this issue, and what they did to fix the problem. It usually takes a few calls to get an issue resolved.
Step 5 ~ Dispatch the top dog 
When all of the above fail, the top dog comes to the dealer. We have a regional guy that travels to dealers to help fix the REALLY broken cars. There is warranty criteria that requires him being dispatched. I am pretty sure I can’t talk about what that is. This is the guy that has all the connections to the really important people in the company.
The guy we have now is pretty awesome. He worked as a VW tech line guy for years. I acutally worked with him years ago, when he was a tech line guy.  This is basically the last line of repair. I have not ran into a car that between the regional guy and myself, couldn’t be fixed.
Step 6 ~ T.M.I.
If it comes to this, its time to T.M.I. or Trade Me In! I heard that saying on CarTalk, btw. I think the more appropriate thing to say is buy back. There is lots of legal mumbo jumbo about buy backs that I really don’t care to talk about. I am mostly just joking around about trading cars in.
More often folks will trade because the repair is too costly, not because I can’t fix it.

It is no secret that dealers have the most state of the art diagnostic equipment in the industry. Everything from our $1100 battery testers, to our $12,000 VW scan tool.  In fact, the amount of dollars that are spent on special tools and equipment is truly unbelievable. With all that money wrapped up in scan tools, many folks think that they are magic boxes that fixes cars.

The high dollar equipment is just another tool. They are VITAL to repairing most cars, but they don’t fix cars. Would you believe me if I told you a wrench fixed a car?, NO, the wrench was needed to fix the car, it was the mechanic that fixed the car.

I can’t tell you how many times I have heard

“You can just hook it up to the computer and KNOW whats wrong with my car!”

Well, the truth is YES and NO. When I hook a car up to the scan tool, I read the information that is stored in the car’s computer. That information gives me the system that has failed. It does not say “replace this part”.

Take an Airbag light for example. When I use the scan tool to check faults, it will tell me the area that has a problem. If the fault is for the drivers airbag(the one in the steering wheel) that does not mean the airbag is bad. It just means that the system is faulty. The actual problem could be:

  • It could actually be the airbag in the steering wheel
  • the Airbag Module might be faulty
  • It could be the wires from the module to the airbag in the steering wheel
  • the “clock spring” might be faulty(see the bottom of the post for a description of this part)
  • the battery voltage might be causing a false error

Now, the scan tool will not say which one of these things have failed. That is where a mechanic comes in. The testing of components is where the problem is found. That is where the knowledge of the car, and the specific system is vital. It would be almost impossible to fix one of the failures listed above, if I didn’t know how it worked. I will say advanced diagnostic techniques for another post.

I think the issue comes mostly from service departments doing a poor job of helping cusotmers understand the process. Has your mechanic or service advisor ever taken the time to explain how this works? I would be willing to bet that very few have done that. I have heard it explained like this

“The diagnostic fee is $100. We will hook it to the computer and then tell you what is wrong with your car.”

That statement doesn’t really seem like your getting $100 in value does it? It just feels like a customer is paying $100 for a few minutes of work. If all things go right, hooking a car to the scan tool takes just a couple of minutes. –side note, that rarely happens, scan tools can get stupid sometimes– 🙂 Where the value comes from is

  • What the mechanic knows
  • the diagnostic equipment
  • the information available about repairing the car
  • special tools that it takes to fix the car.
What do you guys think? Does your mechanic/ advisor do a good just explaining things, and helping you understand what they are ACTUALLY doing? Do you even care, as long as the car is fixed?
**From above, A “Clock Spring” is what electrically connects your steering wheel to the rest of the car. It allows you to have a horn, and buttons on the steering wheel, and still use them with the wheel turned. The newer ones are a ribbon cable wrapper in a plastic housing. It has enough cable to allow the wheel turn fully in both directions. With the fault I talked about, this part is the most common failure.**

This car came in one day last week.  The customers complaint was “My car is making a ticking noise”.  The noise was strange, it was loud when I was standing right a the engine, but when I walked about 10 feet back, it was super loud.

Complaints like this can be really tricky. On the one hand, some engines are just louder than others, on the other, I can’t just say there is nothing wrong. Also, there are a lot of factors that play into engine noise.

  • Is the oil in the engine right, both level and quality
  • Is other maintenance up to day
  • Did the customer do something they are not telling

I spent about 20 minutes listening to the engine with a “stethoscope”(in quotes because mine is missing so I use a long screwdriver). I narrowed it down to the valve train, the upper end of the engine. Since the VW 2.0t TFSI engine is kinda strange, the initial diagnosis was pretty easy. Removing a valve allowed access to check part of the valve train.

It turns out that the lobe on the intake cam was worn funny. Further inspection revealed more damage.Two of the rockers had floated off the valves(if your not totally sure what that means, don’t worry just know its bad.)

Now that I know what was wrong, it was time to find out why. I checked the faults stored in the engine computer. The check engine light was not on, but the ECM(engine control module) still had information stored. The fault stored was for “Engine over-reving”.  That means, at some point, the engine was spinning too fast. That can cause the type of damage that I found.  The ECM has fail safes built in to prevent this from happening. The ONLY explanation is the guy missed a gear on a down shift. That would mean that he shifted from 6th gear to 3rd gear, or something like that. The engine revved to 8400RPM. Thats about 20% too fast. The ECM has no way to prevent this from happening.

Now the customer is faced with a $2000-$3000 repair on his 2010 GTI with only 16,xxx miles. Its sad to see a car that I really love need that type of repair.

What do you guys think, should he fix it? Trade it in on a new car? I would LOVE to hear what you think.

 

 

This is a little video of the Jetta that I was working on today.

I got the car around 11:00.  The customers complaint was that the windshield wipers would stay on ALL the time.  I spent the better part of the afternoon trying to figure out what was wrong with the car.

This type of car really makes ya put on the thinking cap. Every time that I would press the horn, the wipers would move fast, and the high beam indicator would come on. CRAZY problems!

Below are some pics of what I found.  I am still not 100% sure whether I fixed the car.  I replaced the fuse block on top of the battery.  That seemed to help, but I am not completely satisfied.  I will keep everyone updated on what happens!

Have a GREAT weekend!

Charles

[slideshow]