Passat (B5) :: ECU And Engine Running Rough
Aug 27, 2012
My car recently started running rough (felt like it was misfiring). I took it to a local mechanic who went through all the normal possible problems and determined that it was a computer issue but did not have the equipment to diagnose it. I then took it to a VW dealer who said it was a bad ECU. They wanted a fortune to replace the unit so I sent it to a ECU repair shop in the UK. The repair shop said there was nothing wrong with the ECU and I have since put it back in the car which still continues to run rough. What else may be causing this issue especially considering that the VW dealer said it was a bad ECU but the repair shop said it was not?
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So- I take the variant in for a 65000 mi service- i.e oil change- and to get the recall done on the crankcase hose. I pick it up, drive out, and at first stop sign --- it starts running rough and engine light comes on. Take it back- they throw the computer on it and it throws a code for vacuum leak connected to brakes.. they take it back-pick up next day---they had to replace the brake booster (under warranty, extended-nice of em, I guess), because, they say, the cowling plug was plugged and water filled the booster. I HAD smelled musty water smell. But- why did it just go in the shop?? 60 bucks to unclog drain- W.
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I'm having an issue with a 2008 Passat 2.0T. Engine ran rough one day and check engine light came on! I get the VagCom out, scan the ECU and get misfire on cylinder #2 and #4. Car has 109 000km. Plugs were never changed so I order some new OE Bosch platinum iridium plugs. Go for test drive after having change the plugs and I still get misfire on both cylinder number 2 and 4.
I know coil on plug are prone to be weak on those engines so I go ahead and order 4 new coils which are pretty low cost which is good. Once install on the car I go again on a test drive. car ran really smooth and no check engine light came on. I said fine! I fixed the problem only to discover the day after that the CEL decide to come back on I scan again and this time only get misfire on cyl #2 with fault frequency of 39.
I suspect my injector to be bad but before I decide to remove the intake manifold and spend another 2-300$ in parts. Any way to test my injector with VagCom in order to see if that really is my problem. Also heard the PCV could be a problem but i hardly doubt it would throw a fauly code on just one cylinder.
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I have an 03 Passat with about 70K miles on it. My daughter put rug in it this morning (about 7 gallons) and since then the check engine light came on and the car is running really rough at stops. While accelerating, it seems to be fine. It is also getting about 10 mpg less than normal. MIL codes: P0300, P0301, P0302, P0303, P0304, and P0171. He said the P03xx codes were related to misfirings on each cylinder. The P0171 is a bank 1 failure (?). What do those codes really mean and could they be related to bad gas? Sent her off in my TDI JSW so she's not out on the highway if the Passat decides it doesn't want to go anymore.
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So I was driving my 2001 1.8t last night and put the pedal to the floor to make a yellow light and the check engine light began to blink and the engine started running very rough ever since. It idles very rough and it seems like I have lost a lot of the power.
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Drove fairly fast (160km/hr or 100 miles/hr) then took an exit down a ramp and had to stop at a red light. Noticed all of a sudden that the engine was running bit rougher and then noticed the yellow engine light blinking. I know to turn off the engine immediately when this occurs but then all of a sudden engine light turned off and car was running smooth again.
Car has been reliable for 7 years - proper maintained, synthetic oil, 171000km, timing belt changed, burns very little oil, good torque. Should I have it checked by the dealer (fantastic fair vw dealer)?
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I dont know if this is related but my ignition switch went a few weeks ago, I got the part in the mail this week and was planning on changing it today, but a few days ago my 99 Passat v6 started bucking, kinda like it did when i needed motor mounts...but my engine is really weak and rough. I opened the hood and saw that my air filter hose was disconnected right after the MAF (or at least i think its the MAF).... I don't know how long its been sucking up dirty air. but does that sound like they are related? a friend of mine said if i can see the butterfly valve in the air hose, open it up and spray a can of carb cleaner in it, put the filter back on, start the car and let it run, then do it again with another can and it should fix it. I cant see the butterfly air valve in the hose, since the hose goes down behind the engine. Should i just spray it in anyway? or does have to be press on the gas pedal...
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Car has been running a little rough and the MPG has dropped from about 26 MPG to about 23. could i need new coils? the check engine light is NOT on. can they be bad without the light being on?
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So my MIL (Malfunction Indicator Lamp/CEL) came on a while ago. I haven't had the loot to bring it to the dealership so I just kept on driving. At the same time I knew my CV joints were going bad cause I could hear them clicking when I turn. Well two days ago while cruising down the road the motor all of a sudden started running SUPER rough and had like no power. At the same time the MIL started blinking. I was like a mile away from home so I just drove it home and parked it.
Tomorrow I am going to replace the CV joints but I can't figure out how that would have anything to do with the motor running super rough. When I pulled it in the shop tonight from outside, the car was super sluggish and if i would ease on the gas the rpm would go below 1000 and I thought it was gonna clunk. Oh yeah and a couple weeks ago my cruise control quit working! I only have 70k miles on this thing! It's a 2003 Passat GLS 1.8T automatic with just front wheel drive.
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I had an incident in December where we left the house and drove less than a mile when the oil warning came onto the MFD. I pulled into the local gas station and had to pour two full quarts of Mobile 1 in order to bring the level up onto the dipstick.
As the car is still covered by the VW Assured warranty, I had the dealer check it out but was told that this is "normal" though we never had it happen before (owned for two years). Really, two full quarts is normal?
Now, we have had two incidents since then when the car starts rough and the check engine light flashes. With the first incident, the dealer found that one of the coil wires had "come loose." It is back at the dealer now for the second incident, but i don't see a cable coming loose twice in just a few weeks.
Could these be related to the oil incident? Car is a 2007 early build (2006) wagon with the 2.0T ....
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My mechanic tells me I need the intake manifold gasket replaced (check engine light on, engine surging, running very rough). How much damage can I do to the car by doing this repair myself and screwing it up? I've done lots of repairs on my car before -- brake pads, rotors, replace oil pan. I also have a copy of the manufacturer's shop manual.
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My 04 1.8t is running rough with the cel on. i scanned it and cyl 1is misfiring. tried changing plugs. seemed to work while idling but as soon as i accelerated it started running rough again.
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I just got my first dub, and it is a project car. I have had it serviced and it still idles rough when in drive with foot on the brake but idles normal when in park. a
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Had the oil changed yesterday and changed the air filter myself. Car is now running rough, surging, when in drive and stopped. Runs cleanly when moving and surge is significantly less in park and neutral.
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Had this problem yesterday and drove my car home about 3 miles running very rough and very sluggish! I could smell something like burnt oil or rubber when I stop but not too bad_no smoke. We are at a ski resort and will have to drive our vehicle about 70 miles to nearest vw repair shop. Is it ok to drive my passat with this rough condition? I am guessing ignition coil or spark plugs.
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So I've been sick for the past few days and my GX has been sitting in the driveway. I finally started it up on Sunday to run some errands and the CEL came on and the engine was running really rough. So I took it up to the dealership and had them pull the codes. It was showing a problem with the knock sensor.
I had to leave it until today so they could diag it further and see what the real problem was. Turns out I have a freaking rat in my engine and it ate my wiring harness. The service tech told me he jumped back when he took off the engine cover and saw an 8 inch rat scurry away. It is now sitting out in the lot until they get the rat out because they don't want it loose in the garage.
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Our 2.0T (2008 Passat Komfort Wagon) with 70K miles is sitting in a mall parking lot and won't turn over. The lights and accessories all function just fine, and don't change/benefit from a battery jump. DRLs and all dash indicators light up like normal.
We push in the key fob and absolutely nothing happens. No error messages or anything. I tried a half dozen times; no change. Two things to know:
1) The car is under a recall for defective Electronic Steering Column Lock. I understand this can invoke the immobilizer? Car does seem immobilized. (I hadn't gotten the car in for the recall.)
2) The car recently ran rough and threw an Emissions system code. I hadn't gotten that code read, yet, but the roughness sorted itself out. I think this is unrelated and may be a case of "car wash syndrome" as my wife and son occasionally run the car for a minute or less to move it from the driveway to the street.
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We have been having issues with my son's 97 Sierra running rough when it is cold/damp. It feels like the engine is missing.
Today, which is warm and dry, it started running really bad and it was all he could do to limp it home. It seemed like it wanted to idle fine but when he tried to rev it up the tach would start jumping and it seemed like it was missing.
Could this be a bad cap/rotor? The engine has 200,000 miles and we've never changed the cap/rotor. I changed the plugs/wires probably 100,000 miles ago.
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This weekend my CEL went on and stayed there. Everything seemed otherwise fine until yesterday, when the engine started running rough (like it is missing) and the CEL will flash on and off periodically. When I got home, the exhaust smelled like gas. I have an appointment with the dealer one week from today, and am driving my "spare" car in the interim.
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why my truck is running rough the problem I am having is when you push the gas peddle more than a 1/4 of an inch it shudders and has no get up and go and also if say I'm doing 40 MPH and hit the gas you can hear the engine rev up but I will lose all power and actually lose speed I thought maybe the cats were bad and I changed the plugs for good measure but I can't seem to figure it out also I had the fuel pressure checked and its pulling pressure is great/
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I started the car the other day and it was running really rough and engine light was on. I started pulling the spark plug wires and pulling #3 didn't make any difference in terms of decreasing performance where the others all did.
I've replaced the plug, and distributor cap. I've also confirmed with the plug out of the block that it is firing.
I'm not sure at this point what to look at next. This happened overnight, not gradually over time, and apart from running rough the engine isn't making any noises which based on sound, and how fast it happened doesn't make me think its a scoring/compression issue.
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