CHECK ENGINE LIGHT

CHECK ENGINE LIGHT

 VW BASHING

In my humble opinion I think VW manufactures pretty decent cars especially since  several of their models  won car of the year, a few years in a row. In fact VW Polo is probably the least troublesome VAG car and unfortunately the VW Jetta is the most troublesome. However not everyone is impressed with VW and from what goes around  at VW service departments about the flashing check engine light and especially coming from the mouths of VW owners,  borders on disgust and disappointment. Some of the things I've heard them say are:- Volkswagens Suck- and their service departments suck even more. They are an unorganized bunch of monkeys ... VW as a company - customer service is definitely not their priority. The check engine light is how they make money. The Worst customer service I have EVER received.  VW cars need no introduction but they do need constant attention. I will never buy Volkswagen again. As soon as my VW Golf gets out of the shop I'm trading it in for a Hyundai! Volkswagon cars are shit. I'm seriously interested in a "don't buy VW campaign". Never, ever buy a Volkswagen because VW service departments give Toyota cars as loaners. I really loved Jettas before, but now they SUCK. 

Volkswagen do not have an engine number, it an expire date. When I said I drive a VW, the mechanic said "what a shitty vehicle". I don't know how I will sell this disaster of a car! So don't sell it - just trade it in and get a non-VW. The time and effort to fight with corporate Volkswagen will get you no where. Their monkeys do what they are trained to do. Most VWs are lemons and the service people know it. VW quality and service is terrible - I will never buy another VW product.  VW service people are complete fools. Mostly my problems have been with idiot VW repair people, piss poor VW customer service, yep I agree a lot of service departments do suck. VW "wear and tear" - what a load of crap - more like cheaply made, more plastic than metal. The service people at VW are awful to deal with because they know VW sucks. My recent problems with bad service turned to NO service after calling VWoA. Customer service at VW sucks...they are programmed to say: "I'm sorry you are having issues with you vehicle" over and over. 

So, where does this leave avid VW fans like you and me? Do we jump on the VW bashing band wagon or do we take a stand? What I'd like to say in defence of VW, is that since the SAE mandated ODB-II for all makes of vehicles built after 1996  and even supplied a list of generic diagnostic Trouble Codes (DTCs), meaning codes relevant to all cars. Its only a matter of time before all modern day cars start misbehaving and frustrate their owners like some VWs frustrate some of their owners. Little do we know what is happening in the diagnostic and repair, misbehaving and frustration ranks of Honda, Mercedes Benz, Kia, Hyundai,  Opel, Ford, GWM, Renault, Mazda, Alfa Romeo, Bentley, Chrysler, Fiat, Nissan, Jaguar, Lexus, Jeep, Chery, Daewoo, Toyota, Mitsubishi, Peugot, Volvo, Tata, Citroen, Dodge, Proton, Suzuki, Geely, BMW, Isuzu, Porche, etc. Considering most mechanical service departments may not have the necessary electronic savvy diagnostic skilled technical personal, automotive problems are going to be on the rise and more expensive to repair than ever before because unskilled and untrained mechanics are bound to take "like forever" to find the faults by guessing and by trial and error. I personally know of a case where a car  was in for service and repair for 52 days in a single year because the "automotive technicians" could not locate the source of the trouble.

COMMON VW CHECK ENGINE LIGHT PROBLEMS

A typical problem with Jetta / Jetta GLI / Jetta GLI 2.0L T / Jetta LX 5 cyl (2010-2011) / VW  Passat, Beetle, Golf, Tiguan, Routan, Eos, GTI and the VW  Taureg is the Check Engine Light (CEL) aka (MIL-Malfunction Indicator Lamp) that flashes or blinks continually or stays on especially in cold weather which is normally caused by a faulty Check Engine Light sensor. But when the Check Engine Light  (CEL) aka (MIL- Malfunction Indicator Lamp) comes on and the whole car shudders and shakes in an almost uncontrollable manner, not only does it sound expensive but also feels expensive. Check Engine Light  (CEL) aka (MIL-Malfunction Indicator Lamp) is also associated with failure to start, noisy  cranking, backfires, stalling and shaking, rev hesitation, visible black emissions and even engine fires. These issues often flags a P300 (random misfire) which motor mechanics, sorry "automotive technicians" readily pass over as a random glitch, returning the car to the owner saying "no problem found". A glitch that is bound to reoccur whist driving on the inside lane during peak hour traffic, which could consequently leave  the driver stranded on the express way.  This supposedly random error is actually a tell tail sign uttered by one of the ignition coils ( N70, N127, N291, N292) or injectors (N30-N34). A failing Ignition Coil  or a failing Injector gives exactly the same symptoms, upto and including turning on the EPC light (Electronic Power Control), the Check Engine Light (CEL) aka (MIL-Malfunction Indicator Lamp), limits the power and sends the car into limp mode and flags the relevant Diagnostic Trouble Codes (DTCs). Injector DTCs are from P0200 to P0212 and P0261 to P0296. Whereas Ingiton coils DTCs are normally from P02300 to P02335. Unlike older cars that have one coil that could go faulty, which would stop the car in its tracks. Modern day Volkswagen cars, have one ignition coil for each spark plug, implying 4 times the possibility of failure on a 4 cylinder and 6 times  the possibility of failure on a 6 cylinder engine and more ignition coils for the spark plugs per cylinder engines.  If 1 ignition coil or 1 injector fails, the other coils continue to keeps on firing their individual spark plugs. Along with the functioning injectors  keep the engine running but unbalanced due to one cylinder not lagging behind-- because of a dead coil or injector. This shake is so bad that it makes driving the car virtually impossible.  Since, it is very unlikely that 2 coils or 2 injectors would fail at exactly the very same instant, a quick and easy repair method is to keep a new spare coil and injector in the tools box which could be replaced by the process of elimination until the problem is solved.

The other common Check Engine Light  (CEL) aka ( (MIL-Malfunction Indicator Lamp) culprit is the mass air flow (MAF) sensor (G70) which works in conjunction with the Oxygen (O2) sensor to provide the correct volume of air for  stoichiometric calculations.  The MAF is situated between the throttle body and the air filter pan and sends direct predicted air flow data to the ECU, while the oxygen sensor sends feedback data to the ECU so that it can  make the minor corrections to the predicted air mass. Mass Air Flow Sensors (G70) are mechanical devices and therefore prone to failure since their measuring elements tend to get worn overtime, flagging  P1144, P1145 or P1146 DTCs. Mass Air Flow Sensors can possibly cause a wide range of engine problems much like those caused by the ignition coils and injectors. It is therefore essential to download the Diagnostic Trouble code (DTC) memory to determine whether the ignition coils, the injectors or the Mass Air Flow Sensors is causing the problem.

CEL, check engine light, check engine light is flashing, flashing check engine light, check engine light is on, check engine light blinking, check engine light blinking car shaking, blinking check engine light,

EPC Q & A

EPC Q & A

So many Audi, VW, SKODA and SEAT owner are having EPC light nightmares. Sending their vehicles for EPC repair which are often misdiagnosed, costly, ineffective and futile because most mechanical repair personal are not electronically trained hence have no idea of  digital logic and isolation procedures.  Modern cars are strewn with sensors and actuators, network buses, electronic control modules driven by software. To quote a line in Turks and Caicos which goes something like this "... everything changes. I used to be able to take a wrench and get under my car's bonnet and fix my car. Now you need a degree in electronics. Even easy things are difficult now." Replacing automotive components does not have to turn into a 'wild goose chase' where guess work is based on trial and error which now has become the order of the day.  That approach just scares everyone. Upload the diagnostic scan of your car now, so that I can analyse for you before you go ahead and buy expensive parts only to find out that the DTC was incorrectly interpreted.

Question?

I'm Lorraine from long beach. I don't know who you are but you are a God to me. I've been searching the web for months for specific and in-depth information on the "death light" (EPC) appearing on my '99 Volkswagen  Beetle. I have studied your entire blog and will now have a very interesting conversation with my German Car mechanic on how he can detect once and for all the problem. Already $1,000 in with no results. Thank you. I hope I don't have to sell the car just yet (to whom, I have no idea) throttle body replaced-twice so far-but hmm that Cam Bus section is interesting. My radio went into Safe Mode months ago and then spontaneously came back on (we do not have the code) so maybe we should check that path out as well. Again thank you.

Answer!

Hi Lorraine, since you don't say much about the specific problem that you are having other than the "death light" (EPC) appearing on my '99 Beetle, I really can't comment on it. However since it is EPC related, your problem has something to do with fuel delivery and engine torque electronics. Bear in mind that your fuel is under pressure from the tank to the injectors and that the ECU receives inputs from the various pressure sensors. If any of these pressures are below spec, it can trigger an EPC problem. For example, if your fuel cap does not seal properly the low fuel pressure sensor G410 will send a error signal to the ECU which can trigger an EPC fault. Likewise if the fuel regulator sensor cannot equilize the fuel pressure from the high-pressure fuel system it will trigger an EPC fault. Suppose If you were driving on an incline like an on-ramp to a bridge and didn't gear down sufficiently for you Beetle to swiftly climb with ease, the likely hood is that detonation would occur. If this happens, the knock sensors would inform the ECU which translate detonation as insufficient torque and trigger the EPC circuit - limp mode and EPC light. There are several other EPC possibilities but without a diagnostic scan it is difficult to pin point the problem.

Question?

Anonymous. I have a '07 Polo 1.4 16v BUD. I don't have any lights on the dash, but the engine seems really weak through mid revs and is using a bit too much fuel. When I hook up my OBDII there are no faults recorded but when i view the throttle position in real time it doesn't seem to open in a linear manner. As I press the pedal on the road, the throttle valve seems to open slower than the position of the pedal. eg; 50% pedal = 30% throttle position, 80% pedal = 35% throttle, 95% pedal = 40% throttle, 100% Pedal = 100% throttle. As you can see WOT does give WOT at the throttle body, but I don't generally drive with my foot planted on the floor. I am confused why it does this as you would expect the throttle body to open the same amount as the pedal, could it need alignment? I am loathed to take it to the VW dealer for fault diagno$i$ so if anyone has any ideas???? Thanks

Answer!

Hi there. Since you don't have  diagnostic scan its difficult to help you however, the mere fact that you don't have dash light makes it very obviously that you have electrical problems or wiring harness problems. And since your scan tool didn't find any DTCs, further proves that this is the case. The dashboard is normally directly connected to the OBD port in the driver's cockpit and since you have no dash lights you most likely have missing voltages on the OBD port which is most likely needed to perform a proper and correct diagnostic scan. Check your fuses on the terminal 30 line and the relay that supplies the terminal 15  supply line. Once you've exhausted everything else, as a last resort your dash control module could be faulty. Anyway, the acceleration peculiarity that you are describing probably has nothing to do with the dash electronics. Since you car has drive by wire, which is totally electronic (not throttle cable), torque is determined by the ECU which will open the throttle valve logarithmically based on its load and terrain, thus there is no physical correlation between the accelerator pedal and the throttle valve. So, no I don't think it needs alignment but seeing you have an OBD-II scanner, its quite simple for you to just redo the adaptation (described in a previous blog) and take consolation in the fact that you have eliminated it as a problem.

Question?

Hi I have a problem with EPC it came on since yesterday, am worried please help.

Answer!

My friend, you really not giving me much to work with here. But I suggest that read through my blogs pages related to EPC, torque, drive by wire, accelerator pedal sensors, knock sensors,  throttle adaptation, engine RPM sensor, etc. Perhaps if would shed some light on your EPC problem. Remember that EPC problems are related to what the car was doing at the time the light came on. for example, spirited driving / towing / start stop peak hour traffic, etc, Anyway the best way to find blog pages relating to your EPC problem , is to type your search word (EPC / drive by wire, etc) in the search box I provided in the top left hand corner on the first page of my site and click on the miniature magnifying glass to run the search. Happy searching.

Question?

Hi everyone, I would really appreciate some advice from you all. I have a 2002 (52) Ibiza 1.4 Sport (100bph), and have some issues with it. Background: Since day 1 it has occasionally thrown up an EPC warning light, followed by an engine electrics light. They would go away after a day and not return for several months. I had the logs read by a Seat dealer during a service and they said it had shown an intermittent Lambda filter error, and that it would cost £240+ to fit a new one. I passed. Over the last month, this has become an every day occurrence. The EPC light will come on seemingly as I just try to pull away from stationary. The car sometimes (half the time) notably stutters when this happens, then pulls away normally. If I restart the engine, most times the EPC light will go off, but the engine light will stay on. Then, more weirdly, the car has started occasionally stalling at random. No judder, no rough idling, I'll be slowing down towards a roundabout or into traffic, and whilst idling (coasting on the clutch) as I slow down, I'll notice the battery light come on, and the power drop out. Once, the battery light came on, but I was able to rev the engine up and it recovered - the battery light then went out. Mostly, I need to restart the engine though. I took it to a garage called Vee Ws for its annual service yesterday and asked them to look into it as well. They went with a cautious (on my finances) approach, and said they'd do the full service and that hopefully that on its own might rectify some of the issues. After the service, they said the logs showed some intermittent issues but nothing serious. They reset the onboard computer to its basic/default settings and said they hoped that would sort it. They also said they noticed the throttle body was pretty dirty (done 71,000 miles), and that if the service doesn't sort it, that they would try to clean that up and see if it did the job. Anyway, 10 minutes after I pulled away from the garage, the lights came back on and today the stalling re-occurred. I feel like this could turn into one of those 'wild goose chases' where its a case of trial and error, replacing different parts to see if it works. This scares me greatly! Has anyone experienced any similar symptoms, or would anyone recommend going to a proper Seat Dealership/Services team to take a look? I wonder if maybe they may be more likely to find the underlying fault? Having said that, I've always found Vee Ws in Bristolonia competent and most importantly, cost-effective. It may be possible to ask them to try and source used-parts while they try different 'fixes'.. Thanks for any advice, Jamie

Answer!

Hi Jamie,  the fact that your SEAT occasionally throws up an EPC warning light, as well as  the engine electrics light, says that your problem is more likely emission related, hence your intermittent Lambda error. Normally only torque and fuel related problems triggers the EPC light, meaning the engine light doesn't come on. Engine light only comes on with emission related issues.  Considering the age of your car it is possible that the Oxygen censor could be glazed over (end of life) or its wiring connector could be intermittent. The oxygen sensor is a feedback mechanism that instructs the ECU to increase or decrease the fuel supply hence shuddering. But this may not be definite. Without a diagnostic scan, I  am more inclined to say it could be your throttle body sensors not only because your service agent said it was dirty but because of the stalling and stutters on pull away. This seems like the throttle valve isn't providing an adequate air supply when its needed. However if they serviced your SEAT and did the adaptation as they said they did, then its unlikely the throttle body else adaptation would have failed, even though they said its dirty. So its more likely to be your accelerator pedal sensors. I mention this because  the car switches off when you decelerate, implying while your foot was on the accelerator it was OK but by taking your foot off the accelerator the condition changed and the ECU picked of this which could be due to 1 or both intermittent potentiometers. When you initially start the car  the ECU does a self-test by switching on all dashboard lights and if no problems are detected turns them all off. So when you start and the EPC light turns off, at that specific point in time there is no problem, but half way through acceleration while driving the problem is detected and the ECU switches he car off. Intermittent DTCs that do not reoccur during four driving cycles, are automatically deleted from the system which explains why the EPC light goes out after a day or so and doesn't show up months later. Lets have a diagnostic scan and I will have another crack at analyzing your problem.

DIAGNOSING EPC LIGHT PROBLEMS

DIAGNOSING EPC LIGHT PROBLEMS

VW Polo EPC light goes on and the car won't rev. Audi MIL and EPC light turn on and car goes into lip mode. SEAT suddenly has no acceleration yet has maximum of 1200 RPM. SKODA accelerator problem, won't rev. Audi EPC light on and transmission is locked in park.

Audi and VW crankshaft position sensors.

Question?

Hello mate...
My car was running really sweet when suddenly I'm having throttle issues! I was going to my girls house when all of a sudden, smack bang in the middle of the road, I have no acceleration. The car just cut the revs into idle and causing the EPC light on the dashboard to light up. I managed to get it off the road out of the traffic. Several attempts later to get her to rev up but  nope, absolutely nothing. So I phoned the towing service and the dude  checked under the bonnet to make sure everything was in place so he disconnected the battery for a while so it would reset the computer. It still wouldn't rev, so he hauled it onto the truck and brought it to my house. My neighbour Freddy has a VCDS which he plugged in and these fault codes showed up. I'm desperately in need of help because I have no idea how  to  solve this problem?

Chassis Type: 6K - Seat Ibiza/Cordoba
Scan: 01 02 03 08 15 17 25 45 56
Mileage: 97850km/60801miles
-------------------------------------------------------------------------------
Address 01: Engine

Part No: 6K0 906 032
Component: 1.8L R4/20VT SEA 0002
Coding: 11500
Shop #: WSC 78904

5 Faults Found:

18047 - Accelerator Position Sensor 1/2 (G79/G185): Implausible Signal
P1639 - 35-00 - -
18039 - Accelerator Position Sensor (G79): Signal too High
P1631 - 35-00 - -
18042 - Accelerator Position Sensor 2 (G185): Signal too High
P1634 - 35-00 - -
17950 - Angle Sensor 1 for Throttle Actuator (G187): Implausible Signal
P1542 - 35-10 - - - Intermittent
17581 - Angle Sensor 2 for Throttle Actuator (G188) Signal too High
P1173 - 35-10 - - - Intermittent

Answer!

Hay George.This is quite interesting that both your accelerator potentiometers and both your throttle body potentiometers are acting up at the same time. Normally I would say that your accelerator pedal needs to be replaced if only G79/G185 flags repeated DTCs. Alternatively say that your throttle body needs  cleaning and adaptation if G187/G188 flags repeated DTCs. But this is certainly not the case though both these circuits are notorious for "No Throttle Response", limp mode and turning on the EPC light.  However to me it looks more like the voltage supply line to both devices is acting up, that it's intermittent.  Since the throttle and the accelerator are each connected directly to the same control module (ECU) I'm tempted to say that the ECU plug is probably loose or corroded or the fuse holder that supplies the ECU with terminal 30 (12V unswitched) and the relay that supplies terminal  15 (12V switched) needs to be checked for proper contact and corrosion. What I am willing to say is that you have a wiring harness problem, so check continuity between the ECU and the accelerator pedal 6 pin plug and the ECU and the Throttle body 6 pin plug. Make certain to do adaptation afterwards and check throttle valve control in group  060“ (G187/G188),  and especially 62 (G187/G188 & G79/G185), and 63 (Kick-down) and if you have a cruise control group 66 as well.

Question?

I'm Renshaw and I have an Audi A4 1.8T. When I started my car from cold, the EPC light came on and the engine just stalled. Made a couple more attempts to start but engine just cranks and  wouldn't start. After a while I tried  again and it started just fine and it drove fine. The following day  I couldn't start the engine again. So like before I waited a while and it started fine and I drove all week without any EPC problems, until this morning while standing in peak hour traffic my car just died.  After a few tries the car finally started but while I was driving both the EPC and the MIL (check engine light) came on, the engine lost power and was idling at 1200 RPM. This happened a few time over the past month and I'm really loosing my patient with my Audi A4.  So when it happened again I limped to the service agents  who got the 2 DTC errors:  P0321 Ignition/Distributor Engine Speed Input Circuit Range/Performance and P0322 Ignition/Distributor Engine Speed Input Circuit No Signal, but they could get the car to switch off like it did with me. Something like the toothache goes away when you get to the dentist. Anyway, I've search the Internet forums for a  EPC problem similar to mine but found nothing. I still don't have any idea what's going on. Can you please help me and I would be very appreciative and thank you.

Answer!

Hi Renshaw, thanks for your question. The problem you describing is fairly common on Audi which normally flags any or all of the following DTCs - P0320, P0321, P0322 and  P0323  at the same time. This is undoubtedly or rather more often than not caused by your Engine Speed (RPM) sensor signal (crankshaft sensor) that is out of phase. Bear in mind that your car has a DIS and not a mechanical distributor which is normally driven by a gear on the camshaft. This implies that your camshaft / crankshaft have embedded  magnets that energizes  a hall sensor (crankshaft sensor) or an inductive sensor mounted on the cylinder block which  measures crankshaft speed (interval), that provides the engine speed signal to the ECU. It also doubles-up as the signal that determines the time and duration of the ignition (spark) as well as injector timing. Depending on the model, the crankshaft sensor is next to the oil filter. Crankshaft position sensor (G28) failure is also common on the new VW Polo the new Jetta. 

NB!
If you need help with your EPC problem or an explanation of your diagnostic scan and willing to share the findings with fellow Vag owners, feel free to link to this post and upload  your question and a scan of your car. Not every problem can be dealt since there are a fair amount of overlap / common problems, but I will try my very best to answer as many as possible.