Check Engine, EPC, and Traction Control Lights all on, MK4 24V GLI

[D_C]

I have the EPC Light, Check engine light, and Traction Controls hazard light with the MAF code popping from a cheap OBDII scanner from Autozone. I replaced the MAF with a new one and reset the code via an unpluged battery and holding +- together. with code gone, I ran the car for 40 miles. was still hunting for perfect idle. lights came back on at 35miles. I dont have $ to send the car to service. Please help if you can. I looked in the engine bay for a cracked vacuum line but could not find anything.

Lets go back in time, I do believe I broke it. Here is how the problem started - I was pulling into heavy traffic, reved her up and popped the clutch. apparently reved too much cause it lost traction for .001 seconds when i lost ALL power. I Thought i had stalled it (with traffic heading directly at me i tried to restart the engine) engine was running (barley), so it made a slight starter grind. power came back to me in 4-5 seconds (which seemed like eternity with the folks i pulled out in front of were pissed off cause i "slowed down" as soon as i turned infront of them.) EPC Light and Traction control light came on immediately. I can not turn off the traction control light. after two minutes into the drive, the check engine light also came on. It does not keep idle when at traffic lights and stalls out on the freeway. It runs VERY badley when the air is damp outside like Rain or high Humidity...

Please help!

Should I just eat the $99 diagnostic charge?

[24V GLI VRT]

hey i had the same problem with my check engine light after a high rev. look into your plugs and individual coil packs. when the packs are bad the metal sleeve looks burned or tinted green. After spending about 100 on new coils packs at eich vw in st cloud mn my light went out,god luck
24V gli VRT
jake

[GTIVRon]

What is the new code you're getting? Again for the MAF?

[D_C]

Okay, So i spent all day yesterday scratching my head. The weahter in CLE was rainy and 55F. Took her for a ride and all the lights started to turn off. first the EPC light, then 10 minutes later the traction control light. however the Check engine light was still on. After these two lights turned off, the car was running Perfect. NO hesitation, no spuddering. I took it to a mech that could look at the code (again with the ****ty OBDII meter since NOBODY has one in my city OTHER THAT THE STEALER) code this time is P0101 which is MAS out of range. he cleared the code and the car was still running PERFECT. I drove the hell out of it trying to make sure that if it was going to break again, i could get it to break asap. Hard, Slow, Fast or easy... didnt phase it. So i took the $100 i set aside for the dealer and a true Vag-Com test and spent it on Oil, Filter, Wiper blades and in I cabin Microfilter.
Coming into work this morning... Car started PERFECT again. ran GREAT. then about 15min into my commute, EPC Light, then Traction control light... Car running like CRAP again. The weather today is DRY snowy and 30F. Willing to be the Code now is P0101 again...

Could my EGR valve be broken? or the tube? perhaps I when the car rocked (see my first post above) it broke the hose??

[D_C]

VRT- I will pull them and check, Thanks for the reply!

[D_C]

What is the new code you're getting? Again for the MAF?

yes, P0101 yesterday and P0102 twice before.

[D_C]

Quick up-date. Lights again turned themselves off. Car is running good again.. so, I ask again...

Sticky EGR?

[GTIVRon]

honestly i have no clue... LOL. that is wierd...

[D_C]

When im on the highway doing 65+ constantly, is when the lights come on. but at least this time the CEL didnt come on, just the EPC and Traction Control light. driving around town, lights go out... and car drives like normal. I'm going to take her apart tonight and have a look-see at the EGR valve and Throtlebody

[c0ntract_thrilla]

I had this problem with my 24v GTI


I will tell you a few things

1) I sold the car because of this problem.

2) The EPC+MIL + EPS is a sign of a bad MAF, but the MAF is not your problem...

3) If you keep putting MAF's in, they will keep dyeing...

4) Diagnostic at the stealership will return a dead MAF code, they will tell you to replace it and it wont solve your problem.


My issues started after I had my axles replaced, like 20 min after driving out of the bay. They told me it was unrelated.

I eventually sold the car because I was sick of the problems and bought an A4.


The new owner kept in touch with me, he took it here

Settle's Volkswagen Services
810 Old Sambro Road
Halifax, Nova Scotia ?
Phone: 902.477.5556

They solved the problem. (very good shop for VW's)


Repeating this as second hand information, but this is what I was told by the new owner.

Apparently when my axles where being replaced the other shop damaged a set of wires or something near the fender well, where my car was so low, and my fender liners eroded, when it would rain, the water would cause a short and kill the MAF

Long story short, I think you have a short in your harness.Call the shop I posted for more information.

they might need a reminder, it was a black 03 GTI with a Jetta front end on it, kept killing MAF's solution was something to do with wires behind the fender liner.


Hope this helps

cheers

[rajvosa71000]

Since the problem is not with the MAF sensor and maybe the harmess try to see if your coolant sensor connector is wet with coolant? there was a post long time ago about the coolant getting into the coolant sensor connector and corroding the wires...this was a problem with the cars that have a coolant sensor positioned at an 45 degree angle, my coolant sensor is positioned at and even angle 180 degree (flat).
Not sure if it would help, but since you guys are talking about the harness it wouldn't be a bad idea to look at the wiring on your coolant sensor, sometimes if that's an issue the coolant would misteriously travel all the way to the ECU and corrode some wires.

[D_C]

Thank you for the replies.
Again today on the commute home from work, the EPC light came back and seconds later, the traction control light. they are not setting off a CEL however, they go back out after a cool down from the motor and a city drive.
If you see my original post about me "breaking it" does any of these things sound like something that would happen from a hard REV, pop the clutch and turing the wheel all at the same time?

Once the lights come on, the car runs like CRAP again.

I am ready to trade her in, and almost did that same day she started acting normal again... its like she knew what was coming! once acting normal with no codes, i was happy again... I'm telling you, this is becoming a love/hate thing real fast!

What does the EPC actually do? does it stand for Engine Power Control? if so, I can understand why EPC and traction control are linked.

When I have time, I will be removing the EGR valve to have a look. Does anyone have a thread on tips for this? I found nothing using the SEARCH...

[c0ntract_thrilla]

EPC is elctronic performance control module (or somthing like that) it is to alert you of electronic problems.

also there is no CEL, it is called a MIL, big difference as a CEL is focused on engine concerns, a MIL encompass so man other systems in the car that it is to vast a difference to compare.


Also your EPC, and ESP are indicators that this is NOT a coolant sensor problem. If your EPC light is on, you can be sure it is more than a dead sensor or a generic short, usually it indicates a concern with a key sensor shorting to ground.

ESP indicates that it is a short or problem to do with your MAF, when researching the problem I was informed by an VW engine expert that the BDF uses the MAF to calculate engine load and other values that are also used by the ESP system.

If this problem is intermittent and it is happening randomly I think you have a broken wire on the harness or your having a short elsewhere (break or loose wire).

Unfortunately to test and make sure its not a bad ECU port you will need a VAG test tool that only the dealerships have.

Personally, I would get a test light, a wiring diagram, a voltage meter and a friend and I would trace the MAF plug on the wiring harness back and try and move it around to detect the fault.


Good luck, I really regretted selling my 24V. I suggest you either solve this yourself, or take it to a real professional and have it done right.

I only suggest fixing it because a 24v with a neuspeed exhaust is something you cannot live without (but you won't know for sure until its gone)

[c0ntract_thrilla]

Also post your scan results in here from VAGCOM if you can.


The EGR will throw its own code, and it is not tied into either your EPC or ESP system, so you can rule that out

EPC is on because the ESP is not working, as well, it is on because you have a major electronic fault.

[D_C]

also there is no CEL, it is called a MIL, big difference as a CEL is focused on engine concerns, a MIL encompass so man other systems in the car that it is to vast a difference to compare.

Well, I do have the Engine light on now. After last nights commute home, the EPC and ESP lights never shut off, and during my commute back to work this morning, the engine light came back on. What does the MIL stand for and is it the light that looks like an engine?

And, I see your point about this motor...I test drove a car, if I cant get into another VR6 or Audi 3.2, I dont think I would ever truly be happy with it. I cannot afford that anyways, Im so upside down on this car.

Looks like i will need to go to the dealer. however, i want to sit down and talk to the tech that is going to be working on it... not some service mgr that is going to write down a few things i say and give it to just any old tech out there...

[D_C]

Also post your scan results in here from VAGCOM if you can.


The EGR will throw its own code, and it is not tied into either your EPC or ESP system, so you can rule that out

EPC is on because the ESP is not working, as well, it is on because you have a major electronic fault.

I will ask for a copy for sure.

Thank you for your reply, and knowledge of the EPC...

[D_C]

MIL... got it, Whipped out the good ol' manual

Malfunction Indicator Lamp = Emissions Related malfunction (OBD)

[Brett VR6]

dude im in the same boat as you but mine just shuts off all together. im wire hunting as we speak haha

-Brett-

[D_C]

If an Electrical wire is the issue...I would think that I could duplicated the problem the day i had a "clean bill of health" (tuesday) when i DROVE THE POOPY OUT OF IT all day long. 150miles of HARD driving. Slow driving. pop the clutch-driving, ect.

Wednesday... Just driving calmly down the highway at 65MPH about 30 minutes into my commute... the dashboard begins to come alive... looks like a bright orange christmas tree...

[Brett VR6]

see my thread. mine is any sort of highway or low rpm the car will shut off and occasionally throw a MIL and EPC lights

-Brett-

[GTIVRon]

EPC is elctronic performance control module (or somthing like that) it is to alert you of electronic problems.

also there is no CEL, it is called a MIL, big difference as a CEL is focused on engine concerns, a MIL encompass so man other systems in the car that it is to vast a difference to compare.


Also your EPC, and ESP are indicators that this is NOT a coolant sensor problem. If your EPC light is on, you can be sure it is more than a dead sensor or a generic short, usually it indicates a concern with a key sensor shorting to ground.

ESP indicates that it is a short or problem to do with your MAF, when researching the problem I was informed by an VW engine expert that the BDF uses the MAF to calculate engine load and other values that are also used by the ESP system.

If this problem is intermittent and it is happening randomly I think you have a broken wire on the harness or your having a short elsewhere (break or loose wire).

Unfortunately to test and make sure its not a bad ECU port you will need a VAG test tool that only the dealerships have.

Personally, I would get a test light, a wiring diagram, a voltage meter and a friend and I would trace the MAF plug on the wiring harness back and try and move it around to detect the fault.


Good luck, I really regretted selling my 24V. I suggest you either solve this yourself, or take it to a real professional and have it done right.

I only suggest fixing it because a 24v with a neuspeed exhaust is something you cannot live without (but you won't know for sure until its gone)

Wrong. EPC is Electronic Pedal Control. ESP is Electronic Stability Program. I want to bet your problem is either with the harness from your throttle pedal or your throttle pedal (It's not attached to anything but a wire harness, its just a sensor (potentiometer) with a pedal on it).

If that's not it then my next bet is it's your ABS sensor. Just remembered of a friend back in FL. He has an 01 GTI so it's a 12v, but all the same.. His problem stems from his ABS controller not working. To make sure of it he changed it out with somebody elses and the lights stayed off.

Whats making me lean more toward the pedal is because it's affecting your driveability. My friends car didn't run different when the lights came on.

//

You can use a multimeter to check the potentiometer, check for smooth change in resistance, see if it spikes really high anywhere. You can also check the signal by probing the wire, turning on the ignition, and stepping on the pedal, once again look for spikes, in voltage.

Also just thought of another question, do the lights only turn on when you have cruise control on?

[D_C]

Okay, so at lunch today... with the car's error lights on, I sat and listened while inside the car. Giving it gas and letting it try to catch idle when off the gas. Weird deisel sound coming from the motor. so i popped the hood again and wiggle every wire i could see. tugged and pushed on all coilpacks, egr valve plastic hose... everything. well in turn, i got a neat normal idle out of the motor... look inside the dash and lights started to turn off (besides the MIL since it threw a code) car is running TITS again. so, on the trip home tonight, when the problem comes back, im going to pull over immediatley and Wiggle With Intent on idividual items and make note and pause in between... we shal see.
If all else fails, I will keep my appointment book open for my car to be in the Dealer's Hands

[D_C]

Wrong. EPC is Electronic Pedal Control. ESP is Electronic Stability Program. I want to bet your problem is either with the harness from your throttle pedal or your throttle pedal (It's not attached to anything but a wire harness, its just a sensor (potentiometer) with a pedal on it).

If that's not it then my next bet is it's your ABS sensor. Just remembered of a friend back in FL. He has an 01 GTI so it's a 12v, but all the same.. His problem stems from his ABS controller not working. To make sure of it he changed it out with somebody elses and the lights stayed off.

Whats making me lean more toward the pedal is because it's affecting your driveability. My friends car didn't run different when the lights came on.

//

You can use a multimeter to check the potentiometer, check for smooth change in resistance, see if it spikes really high anywhere. You can also check the signal by probing the wire, turning on the ignition, and stepping on the pedal, once again look for spikes, in voltage.

Also just thought of another question, do the lights only turn on when you have cruise control on?

Accoding the the Manual, EPC is "Electronic Power Control" which is a backup program to keep the car running.

Car runs the same with cruise on or off, but i will switch it off and leave it off.. and see what happens. Does the Cruise work off a Vacuum?

[D_C]

Friday Update... I have obtained (borrowed) an OBDII meter. With the Car running like crap with all three of my lights on... I cleared my ONE code (p0102). Car Runs Perfect.
its got to be a lose wire right?

[c0ntract_thrilla]

Wrong. EPC is Electronic Pedal Control. ESP is Electronic Stability Program. I want to bet your problem is either with the harness from your throttle pedal or your throttle pedal (It's not attached to anything but a wire harness, its just a sensor (potentiometer) with a pedal on it).

If that's not it then my next bet is it's your ABS sensor. Just remembered of a friend back in FL. He has an 01 GTI so it's a 12v, but all the same.. His problem stems from his ABS controller not working. To make sure of it he changed it out with somebody elses and the lights stayed off.

Whats making me lean more toward the pedal is because it's affecting your driveability. My friends car didn't run different when the lights came on.

//

You can use a multimeter to check the potentiometer, check for smooth change in resistance, see if it spikes really high anywhere. You can also check the signal by probing the wire, turning on the ignition, and stepping on the pedal, once again look for spikes, in voltage.

Also just thought of another question, do the lights only turn on when you have cruise control on?

Actually you are wrong. Nice attempt to try and contradict me with B.S though

I would say that unless there was a code tossed in the scan, that the problem is not the ABS, ABS speed sensor will throw a speed sensor error code unless the module is bad. If the ABS module went bad, then it would only be the brake warning light, the ABS and MIL on. When this happens the car beeps three times every time you start the car, and VAGCOM cannot connect to your ABS system for a reading. It will give you a com error during the scan. Furthermore, OBDII has such strict compliance measures in relation to the ABS system, your problem should have been flagged right away by someone with Vagcom and half a clue. Also the later production cars have a much different ABS control module that is very uncommon to fail, unlike earlier 1996-2001 cars that are plagued by Bosche ABS control units. (ok I am boring you all, I already said its not the ABS)

Good luck tracing this issue with a volt meter ROFL, you will be tracing it forever ( I would say it is almost impossible) you REALLY need the harness/ecu port scan tool that only the dealers have to be able to check for sure, you could spend a month with a VM and not find what your looking for because the harness is so massive with many other sensors tied into it, also the wiring diagram is a nightmare, and you would not be able to know for sure where the problem lies unless the car is running and you encounter the problem.

start looking for visually damaged wiring because you clearly have a break, not a complete short. If the wire was snapped or burnt out you would have the problem permanently not intermittently. I am not 100% sure, but check your relays, a defective relay could be a culprit to the problem. Also Relays tend to crap out slowly and will work, then falter. (I have had first hand experience)

I would continue to toss out ideas, but clearly I am going to get cut up by the VW vortex experts and their interpretation of acronyms LOL

Oh if none of the above is any help, call a 14 year old in brazil and bitch them out, after all they wired your car

[apstguy]

Does the Cruise work off a Vacuum?

No, the cruise control system is all electronic. Since the throttle is DBW anyways, cruise control is just a program the ECU runs. Only difference between a MkIV with cruise and without is the button on the turn signal stalk.

[PhReE]

Accoding the the Manual, EPC is "Electronic Power Control" which is a backup program to keep the car running.

Car runs the same with cruise on or off, but i will switch it off and leave it off.. and see what happens. Does the Cruise work off a Vacuum?

It stands for Electronic Power Control and it represents the WHOLE system. The pedal, the electronic throttle body, any other sensors required for it's operation, etc. It is sometimes seen in combinations with other lights that may represent a common problem, but SCAN YOUR CAR, make sure to do it with vagcom so you can scan all modules, engine, cluster, abs, etc.. as there may be codes stored in other modules, not just the ECU, depending on the problem.

No, the cruise control system is all electronic. Since the throttle is DBW anyways, cruise control is just a program the ECU runs. Only difference between a MkIV with cruise and without is the button on the turn signal stalk.

FWIW this is also correct.

[PhReE]

Friday Update... I have obtained (borrowed) an OBDII meter. With the Car running like crap with all three of my lights on... I cleared my ONE code (p0102). Car Runs Perfect.
its got to be a lose wire right?

BTW that code is here:

http://wiki.ross-tech.com/wiki/index...6/P0102/000258

16486/P0102/000258 - Mass Air Flow (MAF) (G70): Signal too Low

PLEASE ppl start using the ross-tech wiki (wiki.rosstech.com then click Fault Codes right in the middle, it's easiest to just go thru them page by page vs searching for some reason) to look up your codes! Remember P0102 is not the same code as 0102

We need to get it into the FAQ or something!

[Stizzle]

Look familiar?

[Stizzle]

http://www.facebook.com/photo.php?pi...&id=1562055367

[Stizzle]

...3d time the charm?

http://www.facebook.com/photo.php?fb...070.1562055367

[D_C]

...3d time the charm?

http://www.facebook.com/photo.php?fb...070.1562055367

Link didn't work. Anyway.. Update.
Investigating further, I disassembled my intake and looked into the throttle body and found an oily mess.
Not sure what it is,.but there is a diaphram and hose really close to the T.B. that connects to the valve cover.
This hose haas an alarming amount of oil mixed with water... ?

[D_C]

Okay, so I got to thinking. If there is oil in there (and i dont think there should be) perhaps my engine oil is too high. I looked at the dipstick in a number of different temps, and sure enough, I have about a quart to much. I carfully drained one exact quart this eve and took her out for as spin. checked and re-check the dipstick 5 times as the engine was warming up to 190. the oil level is PERFECT now on the dipstick in 5 different parking lots (tried to make sure i was Level each time) The Jetta no longer has ANY hesitation ANYWHERE. I will be monitoring everything very closely during my morning 34mile One-Way commute.

so this brings me to my next question, What the pluck is water doing in with that oil that shouldn't have been there? it was perfectly clear and riding on top of the oil in that Tube running from the top of the valve cover to the diaphram directly in front of the T.B. I cleaned all of it best i could using an air compressor. that diaphram is now clean, the tube is clean-ish, and I wiped down the T.B. on both sides.

I hope this fixes her. Just a side note, I change my own oil. I changed it in between my first day I had this issue and today (so about two weeks ago) Following the manual, I drained the oil and removed the oil filter. While filling the original 5qt jug back up with the old oil, and having the single 1qt one ready, I was only able to fill teh 5qt jug. I was puzzled but shrugged it off to "my car is running like crap and it may have burned of a qt in the process" Im now thinking that that extra qt was still in there and i didnt let it drain out good enough or angle the car so i could remove ALL of it. (remember i used a lift so the car was flat)

Putting all this together is what made me think of lowering my engine oil level to where the dipstick says.
I'll report tomorrow eve.
Thanks all for your support thus far and wish me luck

[D_C]

Well, That didnt Fix it. Lights back on, again at 68MPH on the highway. once on, car runs like CRAP.

[PhReE]

You prolly had a bit too much oil, ended up with a lot being thrown thru the pcv and possible some got back to the MAF, or the MAF just died like they often to anyways. I would try replacing the MAF.