Golf IV / Jetta IV :: Random EPC And CEL - Can't Communicate With ECU - Doesn't Start When Warm
Mar 31, 2014
So, the very first time it happened was the weekend after I installed my new motor mounts I am not sure if it is a coincidence or if there was something that I touched while installing that is causing the car to act this way. So I notice that it's more common on the wet days even though I have started to doubt this recently as well. The instrument cluster illuminates CEL and EPC for a brief second and the car feels like it looses all power and sometimes even stalls when at idle but then after that goes away it runs like a champ. Also ever since this started happening the car is really hard to start after it sits off for few minutes when at normal running temperature. Right, when it happened I tried to scan it and I thought it was the scanner that was not able to communicate with it but that wasn't it since I have tried over 10 different kinds now( that includes the ones that have scanned my car with no problem before). I did have the CEL to stay on once but I still couldn't scan it and it went away by itself or I have reset it by disconnecting the battery. Its really driving me crazy and I am stuck but not giving up on this car, I love it too much and it's been very faithful to me so far! I mean there was literally two days recently when the weather was dry when I drove the thing without the random occurrence of EPC and CEL but it still didn't want to start when warm. In fact, one time after work after it has been sunny all day it didn't want to start when the engine was still cold as well.
The things I have replaced or tried so far that have not repaired it are:
*New Camshaft Sensor
*New Crankshaft Position Sensor
*New Purge Valve
*New Coil Pack
*Took off and cleaned my Throttle Body
*Checked with and OHM meter as many grounds as i could find between battery and they all checked good(the main engine ground looks good)
*Cleaned MAF sensor
*New Coolant Temperature Sensor
*Checked that all fuses were good and seated
*Verified that the k-line is good.
*Able to scan the ABS module and radio through vag com so i know its something with the ECU communication
That's all that I can remember as of now. the car went through many stages but here is how it looks as of now.
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I have a 99.5 golf gls with an 02' engine in it. 5 Speed, neuspeed supercharged with a bunch of other stuff done to it.
I've had this issue as long as I've owned the car (3-4 years). Starting the car cold, it usually fires right up and can drive it e, no problem. However, when I get the car up to operating temp and turn the car off, if I immediately try and restart the car it either :
A.) chokes but will fire or
B.) will have a long crank and usually starts hard.
Another thing I noticed is that at low RPM right after the clutch has been engaged, the car seems to almost hesitate like something is holding it back, even if I give it more gas. I have checked my codes with Vag com and the only CEL I have it for not having a post cat o2 sensor (picks up that the heater circuit is unplugged). I also have run some diagnostics on my fuel trim and both long and short term fuel trim are within spec. I tested two different mafs and both were around 2.5g/s at idle. Checked for vac leaks and didn't have any.
I have read that a dead/dying crank sensor can give me the symptoms I have, but I seem to be lacking a symptom where the CEL is on for the sensor, and my car doesn't randomly die when driving. So my question is, have any of you had the same symptoms but no CEL?
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Well first the exact car I have. 99.5 Jetta 2.0 AEG. It all started with one loud backfire with a stall at a stop light while in neutral. After that it was random stalling and jerking while driving. So I checked my everything and all seemed well. I replaced spark plugs because they where fouled and nasty. Cables are good. They're near new and tested them with a multimeter. Next I checked my injectors and they are surprisingly very clean.
I had also ran seafoam prior to these problems a few weeks before it all started. Next step was new fuel filter. Old one was nasty and black stuff dripped out. That didn't work. So I checked for vacuum leaks with throttle body cleaner. Nothing. Visually threre is nothing wrong under the hood. So today I changed the fuel pump. Went for a test drive all seemed well. Can out of the bank. Then it won't start. So I wait like normally. And it normally gets me home. Nothing. Will sometimes start but if I'm not holding the gas it dies. I don't know what to do. My only other thing I can think of is the coil pack.
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Last year I had an issue with starting my 1.8t Jetta Gli. Every couple of weeks, the car wouldn't start unless I keep trying or come back after a couple of hours. I then thought it was the cranks sensor and had it replaced. Unfortunately, the problem is back! The idle seems a little jumpy, car isn't as smooth as I'd like it to be. It also doesn't seem to have a strong start. I can't figure out what it exactly is, and I don't want to start changing random parts. I was debating on perhaps getting a new fuel pump, coilpacks...
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Mmkay.. 2000 GTI VR6.. Will start initially, when engine is cold (sat overnight, or through the work day) but once the engine is at normal running temp, if you shut it off, it wont start. Acts like its out of gas.. have to "prime" and keep hitting the gas pedal while cranking, to (sometimes) get it to start when warm, and then it runs like crap until I get a few miles down the road.
Brand new plugs and wires, and just this evening, pulled a plug, and its obviously fouled, and covered with unburnt gas. Coil Pack maybe?
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I've got a Mk4 Golf 2.0L with 136k on the clock. Hasn't really given me any problems in the past year of ownership till now. I recently picked her up from the shop for a rear axle beam replacement. When I picked her up she drove fine. I headed to class for the day and she sat in a parking lot for 6 hours or so. I hop in and try to fire her up and nothing. Had to have her towed back to my apartments. I've checked fuses, spark plugs were recently replaced but I am getting no spark. When I crank it I do hear the fuel pump and I can smell gas when I crank it. The rpms go up just a bit, 100-200 range. Going to check out the crankshaft sensor later on. maybe it could be the coil pack as well? I don't know a huge amount about these cars, only some info. And I sadly have no access to a scanner to check for codes.
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I have a 120k miles manual 2000 jetta vr6 12v. I was having check engine issues so i put in a reader and showed me problems at catalytic converter. I don't remember the code, and no longer have a reader...
I was told to replace the oxygen sensors in both banks as well which i did.
I opened up catalytic converter to inspect and now the car will get no spark, the engine turns, and the display shows engine stop.
I was also told to put the oxygen sensor further away with an extension cord but not sure if that plays a part.
Does the catalytic converter is causing it to not spark?
Could there be an issue with maybe a sensor at the crankshaft that checks for motion?
What the starting sequence and dependencies are or what failures I could have that prevent the spark?
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I have a 03 vw jetta gli and whenever the engine is warm when it was recently on, takes a while to start like 3-5 second but normal when it is a cold start..
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Car doesn't seem to want to start when warm.
1.8T AWD, 02J swap, no clutch switch (I can start without pressing the clutch).
Cold start, cranks and starts on a dime, after the car warms up and I've turned off the car, say went for a quick grocery run, the car won't start afterwards.
No cranking, nothing. Fuel pump primes, then not a sound. Everything on the dash lights up just fine. No starter motor noise, no clicking.... nada...
Fairly new starter motor pulled from a junkyard donor. Can't think of anything else.
Last time I got stranded in a parking lot, I gave it a few whacks with a tire iron and the car started just fine. Could it be a bad solenoid?
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Okay so my 2003 Jetta GLI normally starts without a problem. But it seems like whenever it gets cold (below about 40) it doesn't even try to start. I turn the key and nothing happens, the engine doesn't crank. All the lights turn on like normal and they're not dim so I don't think it's the battery. It'll still start if I roll-start it, but there isn't any sort of hill for a few miles. Normally once it warms up later in the day it'll start up.
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My 01 Jetta 2.0 started having issues a few days ago. The engine would crank, but wouldn't start. Wait a few minutes and it would start right up. I go to start it the next day and it would crank, but not start at all. I pulled the P0322 code and replaced the crankshaft sensor along with a new fuel pump, and spark plugs just to be safe.
Next, I checked for fuel and spark, which I have both. The car still won't start and seems to lose a charge on the battery pretty quick. At this point, there are no codes showing up. Could the engine be flooded from trying to start it so much?
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I bought this car and I've changed out the Clutch Position Sensor, the black one on the clutch mount. Started to work and start but now it's doing the same symptoms as before. So here is what is going on.
1. Randomly doesn't start, full power comes on, and fuel system turns on, immobilizer works just fine as far as I can tell (key light turns off)
2. Cruise control doesn't work (which lead me to the CPS)
3. High revs between shift, once I push the clutch to shift it revs up high, I noticed that if I stay under 3k it doesn't do it as much, but if I go HAM on it it revs up about 1k rpm more than at shift point. But if I shift nice it revs about 2-400 rpm.
It's been tuned by C2 Motorsports, done by a certified mechanic, that's the only mod on the car, besides suspension. I bought the car and dropped 1100 to fix it to drive right, newish throttle body, and a major vacuum hose, and the tune within a month of getting the car and the tune was to mainly flash the ecu so it wouldn't pull two codes for a leak that wasn't there anymore.
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My 2003 Pontiac Grand Am often doesn't start in warm weather. The engine will crank but not start, but if I then leave the key in the run position for exactly ten minutes, the security system seems to calm down and I can switch it off then start the car (a kind tow driver taught me that trick). This doesn't happen in the winter in Pittsburgh, but might happen one start out of six in the summer.
I had the ignition cylinder replaced once, and it took care of the problem for about a year. After it came back, I was told to do exactly the same thing again. At first I decided to punish the dealer by spending another summer loafing in parking lots, but this year I can't take it any more. Should I replace it again? Should a dealer warrant the longevity of the repair?
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I have a 1996 VW Jetta GL 4 cyl. 2.0L. When the temp. start to warm up the car won't start. I don't know if its the temp. outside, or in the cabin of the car. all the dash lights turn on, and accessories turn on. sometimes I hear a clicking noise, which I think is the sound of electricity going to the starter. I have replaced the starter, alternator, & battery. I had a family friend mechanic look at it for about 3 hrs. and he couldn't figure it out. I have a suspicion that it might be the ignition switch faulting out, but how would I know for sure with out taring apart the steering column?
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I have a 01 wolfsburg jetta with aw engine code .. I have replaced and gaped spark plugs all 4 coils , DV. As well as fuel filter . Sometimes it runs fine . It misfire at random times most often at WOT. ..and I've noticed almost always when fuel level is low.. installed a boost gauge .. after disconnecting battery to reset ecu it boosts 10psi and runs strong .. however 1 or 2 WOT and it will misfire and then I won't boost over 4-5 PSI .. worst of all I get no CEL not even blinking .. I have also located a leak in the brake booster line . Does this affect it at all? ..
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It all started a few months ago.... I started my car, and it started noticeably misfiring, CEL flashing and everything. I scanned it with my vagcom and it came up Cylinder 1 Misfire and Random Multiple misfire. I popped the hood, made sure everything was seated correctly, and shrugged.
Ordered some new wires for it, since it had 80k miles on it with original wires, I figured why not. The misfire didn't come back.
A few weeks later, same thing happened. Misfires, flashing CEL, same codes. I ended up driving it the 5 minutes to work anyways and figured I'd look at it later after I got off.
8 hours later I started it up again, ran like a champ, no CEL on. The problem didn't come up again for 3-4 weeks.
So now, without fail, every month or so, I'll get the same issue. It doesn't matter if it's raining or sunny or cold or warm. But if I let it sit for a few hours, it'll act like it never happened.
Now, I haven't replaced the coil pack yet, simply because it doesn't sound like a coil problem, but I might do it just for the hell of it. New plugs and wires have already been done.
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Replaced my water pump March 2nd using the "From Below" method. Started the car after and the check engine light was on and water pump was no longer leaking. I drove the GTI to Advance (15 Mins away) it drove fine and I pulled two codes.
P0300 - Random Multiple/Cylinder Misfire
P0301 - Cylinder 1 Misfire
The car pulled and drove normally. The next day the car is misfiring badly. Hesitation and bucks when accelerating until roughly 3k then smooths out.
I will swap my coilpacks and check if the misfire moves as soon as I can get my hands on an OBD2 Scan Tool.
From what I understand about the VR6 :
-The water pump runs off the serpentine belt
-Camshaft timing is controlled by the timing chain.
-Timing chain is not affected by the serpentine belt/pulleys.
Questions :
-Can turning the Crankshaft Pulley affect timing?
-Can that be the cause of the misfire?
24V VR6
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It will randomly not want to keep running when I goto start it so I just rev for a min and then it's fine after that. It doesn't happen to often. 2003 Jetta 1.8t
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About a month ago my wife's 2000 Jetta with the VR6 engine in it started acting up and throwing codes. The codes it threw were for random misfire, misfire in cylinder 2, and misfire in cylinder 5. Starting out, we changed spark plugs, fuel filter, and made sure the injectors were clean.
The problem didn't go away so we water tested the coil and wires, but they passed that test. The wires were quite old and out of spec, while the coil was in-spec across all terminals, according to the vehicle service manual, so we installed some new OEM leads this weekend. While installing the leads we noticed a disconnected vacuum line and reconnected that as well.
The vehicle was driving great for two and a half days, then today while I was sitting at a stop light, it started missing really badly and felt like it was going to kill. It did this for about 5 seconds, then recovered and ran smooth for about 5 seconds, before getting really rough until I started driving when the light changed. It didn't do it when I drove it a few hours later at all. This episode didn't throw any codes either.
What could be causing this issue? Would the MAF cause the intermittent missing, or is it possible that the computer is going bad?
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I have a 02 Jetta TDI, I have had the car
For about 8mo, and have been fighting a random limp mode problem the whole time.
I have gone thru and changed the common issues, N75, MAF, actuator on the turbo, and changed all the vacuum lines, fuel filter..... Etc. I'm to the point I want to light the car on fire, and see if the engine light goes off!!! Is there something that I have overlooked.
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I have a 05 GLI and I noticed that on the stock "E" valve my car would get random boost surges. I would barely tap the gas and the boost would build up to 8-10 PSI so I bought the J valve thinking it would solve the problem and just installed it today. I took it around the block and really liked how the power delivery became smoother and the car didn't have any boost surging issues. When I decided to put my foot down I noticed my car was only getting 11-12 PSI throughout the whole power band. Before on the E valve I was getting 16-17 PSI. My car's running a Unitronic stage 2 tune btw. I know upgrading to the "J" valve is a hit or miss but I think it's kind of odd that the car drives smoother but isn't running as much boost. I like how it feels for daily driving but something doesn't feel right.
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