2000 Jetta MKIV ... 2.0L GL
I've been dealing with random misfire codes on my Jetta (P0300, P0301-P0304). I've since replaced the spark plugs, wires, fuel filter, MAF senor, & camshaft positioning sensor but the problem still persists. The misfires occur right on start-up and don't stop which is leading me to the coil pack being bad.
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.
So I picked up this 24v vr6 in florida and it has the folowing codes:
p2181 malfunction in cooling system
p0303 misfire in cylinder 3
p0305 misfire in cylinder 5
p0300 random multiple misfires detected
p1570 engine control module disabled
I am thinking the ecu is fried? otherwise why else would that last code pop up. misfire codes im assuming are related to the ecu because theres new COP on each cylinder, newer starter, newer alternator, new spark plugs. Cooling system malfunction im thinking could be the ECT sensor, apparently the water pump was replaced a little while back.
If the ecu is fried can I buy a new one chipped from like APR or do they need the existing ecu and then they modify it?
I have a mk4 1.8t Gti. Recently I have been having issues with idle and boost. I read the codes and multiple random misfires in all 4 cylinders came up, idle control and the crank, knock, and o2 sensor came up. Shows that system is running to lean as well. I changed the spark plugs and wires, check the coil packs they where done about 1k miles so I expect them to be perfectly fine. When I clear the codes it idles below 9-8k rpms. I also noticed the breather hose coming out of the valve cover into the EGT has a hole melted into it, could this cause any of my issues?
View 2 RepliesI am getting random misfires on cylinders 4, 5, and 6. Mostly on 6, less on 5, and even less on 4. Cylinders 1-2-3 show ZERO misfires. I am using vag-com to monitor these. Mostly doing it on idle, cruise seems fine but occasionally when shifting I feel it when engaging the next gear. It doesn't buck but I feel a little hesitation. Cruising and accelerating I do not feel it. Its very strange. A couple times during extended idling I have even gotten a flashing CEL. Fuel mileage has been pretty bad ever since I got the car in December. Average tank gets me 250-270.
I tried swapping coils with 123, and the problem stayed on 456. Coils are all new since I got the car. Plugs are fairly new (under 5K) and I pulled a couple to check, they looked fine and gap was about .028. I might try a new set but my gut is telling me the problem is some where else. I would like to verify/test grounds but I don't know where the harness grounds out.
I also want to get a vacuum gauge on the FPR, or check fuel pressure at idle. I replaced one cracked vacuum line, i am thinning there might be others since there seems to be miles of vacuum line on MK4's. Also have a new fuel filter to install, mine appears to be OEM and the car has 97K.
I bought this 01 jetta vr6 and now the abs-asr light is on. hooked up my obd II and it said no data. i have two questions first are there different scanners just for Volkswagen and the next can it be reset for testing?
View 4 RepliesCar: 2011 VW GTI MkVI
Mileage: 79k
Configuration: Stock
Warranty/Coverage: None
So I started my car last Monday and the check engine light was on. Didn't think much of it because the car ran fine and there were no immediate symptoms. I was busy with work this week, but noticed some changes in the car's performance over time so I waited till Thursday to have it scanned at AutoZone, which threw the following codes:
P 300 Definition: Random Engine Misfire
Explanation: Lean air/fuel ratio
Probable Cause: Ignition system misfire condition, Fuel injector fault, Engine mechanical condition
P 302 Definition: Cylinder 2 Misfire
Explanation: Vacuum leak on engine
Probable Cause: Ignition system misfire condition, Fuel injector fault, Engine mechanical condition
P 303 Definition: Cylinder 3 Misfire
Explanation: Vacuum leak on engine
Probable Cause: Ignition system misfire condition, Fuel injector fault, Engine mechanical condition
Prior to making any purchases I noticed that I started losing some pickup, primarily in lower gears between 2-3k RPM's. Praying that it was somehow just the coils/plugs I bought the R8 pack for both and replaced them this evening. Engine starts up and continues to misfire. I have not had a chance to have it scanned but it would appear it isn't the plugs or coils.
When the plugs were removed, there was an 'oily' substance on the threads, which also seemed like it could have been burnt off fuel or oil pushed up from the cylinder. Also 2 of the plugs seemed looser than the others and didn't feel properly sealed. New R8 install included proper plugs for STOCK application, as I do not run any tuning, and i installed with the appropriate plug grease added lightly to the threads.
I took the car for a spin with the R8 coils/plugs installed to compare it to how the car was doing prior the install. Car misfires and seems fine (relatively) at idle and revving to 2-3k rpm yields NO change. It is almost unable to accelerate up a hill, or go past 30 MPH without the car shaking and any gear higher than 3rd seems not drivable. I feel these are my potential diagnoses before i bring it somewhere and have it looked at.
In Order of Most Likely:
1) Fuel Injectors
2) Air Intake
3) High Pressure Fuel Pump
4) Electronic Leads for the Coils
5) Battery Needs Changed
6) Chain Tensioner Failure
7) Coils and Sparks are all Bad, and I am an idiot
I would prefer to do this work myself and can afford the parts. I just didn't want to be fooling around all month without a mode of transportation to get to and from work.
Replaced my Crankshaft position sensor and cleared my codes but I'm still getting a P0016 and P0018 error. Car runs fine at the moment. Can't smog and therefore register it till I figure it out. Next step is replacing the Camshaft position sensor.
View 3 RepliesI am trying to get a 2009 Sonata NF with a 3.3L V6 to run correctly and i have tried everything that i can find and still get the problem. The car runs very rich with a strong gas smell. The engine runs rough but doesn't stall. The car has has period where it runs fine and then the issue returns but is in more frequent and steady now. The car will run for the first 5 minutes great if it is cold and it also runs good at full throttle and the check engine light went off during hard acceleration which seems consistent with getting too much fuel. I bought a BlueDriver to read the codes and I love the data it provides but I am learning all the features.
For a little history the car has 95,250 miles. At 81157 miles the check engine light came on and an independent shop replaced the downstream O2 sensor and the light has been off for 2 years until coming back on recently. The code showing was a P0300. The shop replaced spark plugs and the manifold gasket with and oil change for $775. The check engine light stayed off for about a month and 550 miles. The car was taken back to the shop and they replaced the rear O2 sensor for $429 . The check engine light was off for a couple of days and then returned with the P0300. It might go a couple of days without a problem and then it would return.
This is when I got the car and started reading all the forums i could for possible causes. I saw the Tech Bulletin on the Variable Valve Timing Oil Control Solenoids so i replaced both valves. The check engine light returned with a P0303 for cylinder 3 misfire so i figured it was a coil so i replaced all the coils. The P0300 code returned. I check fuel pressure after seeing a post about fuel pressure regulators causing the problem but the pressure was correct. I changed the Mass Flow Sensor figuring it was getting too much gas but no improvement. I bought the BlueDriver so I could see more than just the codes. The O2 sensor looked erratic so i changed the front upper O2 sensor.
I found the Tech Bulletin about the O2 sensors fuel trim readings and realized there was an upper sensor on the back manifold and it was reading -18% so i changed it and now I don't know which way to go. I currently have the P0303 code confirmed and P0300 pending. With the live data the items that looked strange at idle were O2 Sensor Bank 1 Sensor 2 steady at 99.2% and Calculated Engine Load a 21.6%. The freeze frame data from when the light came on has all the short fuel trim at 0.0% and long term at -0.8% for both banks. Calculated Engine Load was 45.9% even though I was trying to drive slowly at 29 mph. Mass Air was 21.71 g/s, I had been running 3 minutes from a slightly warm start, Absolute engine load was 44.3%. Anything else to check or data I should look at?
Yesterday I went to star my 2.0 Jetta and it instantly starting sputtering at idle. After maybe a minute of sputtering the car died. Tried restarting it and it would instantly die after starting. Car threw code P0300: Random Misfire.
As of today the car now runs again with no problems. No codes. I didn't touch a thing and it seems to have resolved itself.
The entire engine bay was wet from condensation due to temperature change. Is there any way this could've contributed to the misfiring? I'm thinking the spark plug wires might have gotten wet and that was causing the misfire.
The car doesn't seem to run that rough.
Replaced coil pack and spark plug wires with parts from O'reilly auto
16684 - Random/multiple cylinder misfire detected
P0300 - 35 -10 - Intermittent
16686 - Cylinder 2
P0302 - 35 - 10 - misfire detected - intermittent
16687 - Cylinder 3
P0303 - 35 - 10 - misfire detected - intermittent
I have searched and browsed multiple websites and threads to no avail. They all seem to be dead ends.
My GF recently picked up a 1.8t (AWW) and we scanned it with vag com before she bought. We knew it had some misfires and a few other small problems so when it ran at higher RPMs we didn't think anything of it.
Fast forward to now after replacing some parts (hoses, coil packs etc...) and still the RPMs seem a little high compared to my mk4 vr6. On the streets in 4th gear, my car stays around 2200 and on the hwy its probably around 3300 in 5th gear at 75mph.
On the streets, her 1.8t seems normal but on the hwy in 5th gear, she's at nearly 4k. So my question... Do 1.8ts run at higher rpms under normal driving?
'02 TB w/ code P0300 / Random misfire. Started the other day when it was very damp out, FWIW. Feels like ur driving on rumble strips during acceleration. Rough idle also. It does not do this continually though as after a while (minute) it clears up and runs smooth for a while then runs rough & light will again for a while. I seafoamed it today since it been about 60k since last seafoam. I thought that might have worked until I drove about 20 mile and it went rough again. I also cleaned the oil out of the cam sensor elect connector, since that caused rough running before, although it didn't throw that code. It seems to be very intermittent. '02 TB, 185k miles, orig plugs changed at 125k. Is it actually just going in & out of a limp-mode? O2 since it's random ???
View 14 RepliesRecently i started the car and it was shaking more that usual. the CEL light came stating P0300 with random misfires. It sounds and feels like misfires so i believe this is true.
View 10 Replies2004 GMC Sierra 2500 HD, 227,000 miles 6.0L V8.
While driving up hills or increasing load, the CEL will flash multiple times, I pull over as I know CEL flashing is not good. I turn the truck off, allow it to sit for a few minutes, whip out the code scanner, only code that was there happens to be P0300. Truck has poor MPGS, idles rough, loss of power. this happens every time I drive this vehicle as I use this truck to pull my trailer that weighs around 4000 lbs. Problems come and go. Some days I can drive the truck for an hour with no problems, come up to a red-light, BAM, CEL is flashing, truck is bouncing side to side due to the poor idle, other days this happens while sitting in the parking lot of my job with the ac on.
Truck has been to the shop several times as I'm no mechanic. Parts replaced are as follows:
- Fuel pump
- Throttle Body
- All plugs
- All wires-All Coils
- Intake Manifold Gasket-
- Battery
- Sensor 1 Bank 1 O2 Sensor
- Sensor 1 Bank 2 O2 sensor
I have a 2004 Hyundai Santa Fe 3.5L V6 when i was driving a couple of days ago the check engine light flashed and after a while it stayed on the codes are P0300 which is a random misfire as well as a misfire in cylinder 2, 4 and 6
I replaced all 6 spark plugs and the 3 spark plug wires still the same issue. The car hesitates when accelerating when i accelerate it looks like it wants to stop the rpm goes to almost zero and then it moves and so on. the rpm goes up and down like crazy.
Sometimes it won't move past 1000 rpm I'm moving 60mph and still on 1000rpm and sometimes it works just fine like there is no issue at all. When idle the car is fine and everything seems normal it stays on 900rpm. The car has 158K miles on it.
I uploaded a video to show you what's happening to the tachometer when I accelerate [URL] ....
I'm on a limited budget I'm thinking of changing the ignition coils but i want to make sure that's what is causing the problem first because i spent 200$ to change spark plugs and wires and the mechanic didn't fix the issue.
I hookup an OBD2 tester on my Prius 2014 Plugin and saw the OBD2 P0300 - Random Misfire. I did a reset and the error still came on. I also tested my friend Prius 2014 Plugin which is factory stock and had the same error. Wonder if that is by design or not. Going to take my ride into the dealer on Friday for my 25K maintenance and have them look into that error. P0300 can be anything. Hopefully doesn't cause more problems down the run..
View 3 Replies2005 gti 1.8t having really rough idle and misfires at idle fine while driving pulling codes:
P0300
P0301
P0302
P0304
Unplugged MAF and didn't make a difference...
So I bought a used 1.8t back in august. My second golf, up from an mkiii and I love it. However, the previous owner installed a CAI and being that he lives in the desert, probably never had any issues taking on water. Fast forward to my problem, got caught in a rainstorm, limped it home with the CEL and the traction lights on. it died like three times trying to get it home, but it still would idle when I parked it.
Now I've used the search feature extensively on this problem, and what I've down so far is to take off the intake and reroute it about six or seven inches from the maf, I've cleaned the filter, maf, pancake pipe, and SMIC with denatured alcohol and those are all currently drying. When I took the IC off, specifically the connection between the pancake and the IC, a good three cups (~30oz/850sillyliters) of water dumped out.
Again, my car still was idling when I parked it. Scanned the CEL and got misfires and maf low air codes. Before I started tearing down the intake I took the coils and plugs out and put my shop lights above the valve cover to generate a little heat, maybe make a lil water evap from the cylinders. I live in a pretty arid climate, IE all the water that fell onto my garage floor was gone in 24 hours. Prolly wishful thinking but whatever.
My plan next is to put everything back together when it's all dry, pour a lil oil down into the cylinders, and crank it while the spark plugs are out. Hopefully any residual water will shoot out, along with the oil/gas, and I can go back to enjoying my life.
Also, the intake is hot. I'm thinking any water that made it past the intercooler would've been steam/vapor and I shouldn't need to remove that? Also it seems like it's in a conformation that would force any residual water to drain either into the cylinders or back into the intercooler, so I really don't see any gains by removing and cleaning it
I have an 03 vr6. I'm getting codes p0300, 0303, and 0304. I changed the plugs and the coils and still has changed nothing. In the morning when I first go to start the car it has a rough start and idles rough. But after letting it warm up it is fine. It drives perfectly fine, no misfires. None of this started happening until the car ran hot a few weeks ago. Did a compression test and everything came up fine. So would could my issue be? I'm at a loss here. I was thinking fuel issue but if it was a fuel issue, wouldn't it run rough all the time?
View 15 RepliesOK - so is my engine computer toast? The other day on the highway on the way home from work, my check engine light started to flash, and the car on cruise decelerated from 80MPH (ok I was speeding) to 70, and flooring it didn't make is speed up, and that's when i noticed it was shaking a little, so i pull off the highway and it's as if a spark plug was pulled.
So I made it to a parts store to have the code read, then started it back up, all was well. As if nothing ever happened. So I dismissed it as a pocket of water in the fuel or some other oddity.
2 days ago it happened again on the highway. So I pulled into the shoulder, shut off the car, and started it again. Runs fine. Engine computer?