Engine check light comes on and flash

[SHUIJING]

Much appreciated in advance for your time and help.

My car is Jetta 2001 VR6. Currently its engine check light is on and when I speed up, the light also flashes. Code reading is about clyclinde #2 misfires. I changed sparks,cable,ignation coil/coil pack. But it still has the same problem. Any comments please. Thanks

 

[Patio]

是不是很少跑高速？买两瓶fule system cleaner，一瓶半箱油用，另一瓶整箱用试试。不过能跑几百公里高速效果最好。

 

[SHUIJING]

一语中地, 确实很少跑高速. 我会是一是你的方法. 再汇报.

 

[Behelpful]

light ON, 通常不是大问题； flashing，通常不是小问题！

 

[SHUIJING]

qqh to you. Thanks

When the light is flashing, it means not a sporadic fault - it means the fault is repeated. You should have it looked at.
If the light is on solid, sometimes maybe a sporadic fault or a fault stored in system.

If you don't mind, I can run a vin # check for you. As I recall, there might be a campaign or tech bulletin for that kind of problem. No guaranty though.

BTW, it would be helpful if you can give me the part # for the ignition coils that you have changed.

 

[SHUIJING]

Maybe it is good now.

With your help and after reading the following article, it looks like i (at least temporarily) fiexed the problem. This morning, the light does not flash, although it is still on.

What I did is to check the cable/wire for cylinder#5 and found it is loosed.

Thanks all and I will keep you updated after I clear the code.




===========================


This is a proper DTC. I think (though I am not sure) that misfires are detected by measuring small deviances in engine speed and calculating the cylinder at fault from other engine data. Note that if you are seeing a misfire on only one cylinder, the cause you are looking for is specific to that cylinder. It could be mechanical such as valve problems. It could be a faulty injector. It could be a bad plug or shorted ignition wire. It is unlikely to be any further up the engine management chain than that. The coil in this car is a set of three double ended coils. They fire the cylinders in pairs: 1/6, 3/4, and 5/2. So if it was the coil you would likely see misfires on cylinder 5 as well.



Given that, I'd examine and maybe even try swapping out the plug and wire on cylinder 2. Also run a compression test. Then test the fuel injectors.
Having the Bentley manual - probably the CD version - is a necessity. Having access to a VW scan tool or VAG-COM is very helpfull. With that, you can run the car and monitor the cylinders and see the misfire counts in real-time. Indispensible to tell if it is really fixed. And it enables you to run the fuel system and injector tests.
Last summer I had the experience of debugging misfire codes on my daughters 2.0L. You might find some of the information in that discussion usefull along the way:
http://tech.bentleypublishers.com/thread.jspa?forumID=52&threadID=10326&messageID=78001#78001



http://tech.bentleypublishers.com/thread.jspa?messageID=114214



http://tech.bentleypublishers.com/thread.jspa?forumID=52&threadID=10326&messageID=78001#78001

 

[SHUIJING]

it blinks again. any suggestions? thanks

RT

With your help and after reading the following article, it looks like i (at least temporarily) fiexed the problem. This morning, the light does not flash, although it is still on.

What I did is to check the cable/wire for cylinder#5 and found it is loosed.

Thanks all and I will keep you updated after I clear the code.




===========================


This is a proper DTC. I think (though I am not sure) that misfires are detected by measuring small deviances in engine speed and calculating the cylinder at fault from other engine data. Note that if you are seeing a misfire on only one cylinder, the cause you are looking for is specific to that cylinder. It could be mechanical such as valve problems. It could be a faulty injector. It could be a bad plug or shorted ignition wire. It is unlikely to be any further up the engine management chain than that. The coil in this car is a set of three double ended coils. They fire the cylinders in pairs: 1/6, 3/4, and 5/2. So if it was the coil you would likely see misfires on cylinder 5 as well.



Given that, I'd examine and maybe even try swapping out the plug and wire on cylinder 2. Also run a compression test. Then test the fuel injectors.
Having the Bentley manual - probably the CD version - is a necessity. Having access to a VW scan tool or VAG-COM is very helpfull. With that, you can run the car and monitor the cylinders and see the misfire counts in real-time. Indispensible to tell if it is really fixed. And it enables you to run the fuel system and injector tests.
Last summer I had the experience of debugging misfire codes on my daughters 2.0L. You might find some of the information in that discussion usefull along the way:
http://tech.bentleypublishers.com/thread.jspa?forumID=52&threadID=10326&messageID=78001#78001



http://tech.bentleypublishers.com/thread.jspa?messageID=114214



http://tech.bentleypublishers.com/thread.jspa?forumID=52&threadID=10326&messageID=78001#78001

 

[狗P不通]

RT

sometimes, it has more than one trouble codes. What other trouble codes did you get? CEL blinking is very likely that the oxgen sensors gone.

 

[SHUIJING]

Done

After changing pre-cat O2 sensor, my powerful engine comes back..

Thanks very much for all of your time and help. Thanks


BTW, I bought a repair manual and you have the same modle, i would like to share the info to you.. 2001 Jetta VR6 gls

sometimes, it has more than one trouble codes. What other trouble codes did you get? CEL blinking is very likely that the oxgen sensors gone.

 

[狗P不通]

After changing pre-cat O2 sensor, my powerful engine comes back..

Thanks very much for all of your time and help. Thanks


BTW, I bought a repair manual and you have the same modle, i would like to share the info to you.. 2001 Jetta VR6 gls

you are welcome. thanks for your kindness. jetta manual is not suitable for my car.

 

[YINGWA]

Much appreciated in advance for your time and help.

My car is Jetta 2001 VR6. Currently its engine check light is on and when I speed up, the light also flashes. Code reading is about clyclinde #2 misfires. I changed sparks,cable,ignation coil/coil pack. But it still has the same problem. Any comments please. Thanks

If your car is using Octane number 87, You CAN try using PetroCanada 91 (not 87).