Volkswagen GTI Forums - My Fast GTi banner
1 - 20 of 32 Posts

·
Registered
Joined
·
27 Posts
Discussion Starter · #1 ·
December 9th, I noticed minor hiccups when slowly accelerating in second or third gear, perhaps from 2000 to 3000 rpms. My brother (the knowledgeable individual of the family) and I were not able to identify the problem, so we waited until the issue graduated to a more noticeable state.

Two weeks ago, my CEL appeared. I had my brother read the code, which stated I had a cylinder 2 misfire. I have replaced all four coils and all four spark plugs. With the engine running, my brother had me spray electrical cleaner over a series of gaskets to test for leaks while he observed data on his diagnostic device. A conclusion has not been made and options may be dwindling. Further testing will have to be conducted to see if this issue is more apparent when the engine is cold or hot. I have read numerous misfire threads within this community. Unfortunately, I do not think they apply to my situation. If I have missed a certain misfire thread that does apply, please point me in the right direction.

Noteworthy information:

I own a 2008 GTI with the TSI engine.
My vehicle has approximately 62000 miles
I have replaced all four coil packs
I have replaced all four spark plugs
I have tested known gaskets for vacuum leakage

I wish to see if the community can generate an idea or some avenue to prevent progress from stagnating. Thanks in advance to those who contribute constructive theories. Ask if additional information is required to provide a more accurate response.
 

·
Registered
Joined
·
27 Posts
Discussion Starter · #3 ·
bad injector?
I have not done anything to check the injectors. Would a faulty injector cause intermittent misfires? Can that part partially work rather than functioning or not functioning altogether?

As I become more cognizant of the vehicle's reaction to the accelerator, I am confident in stating the hiccup occurs when I am cruising as well. However, I am unable to feel anything cruising at higher speeds, such as 70 MPH, in sixth gear. This could mean it does not happen at higher speeds or that it does occur but I am unable to feel it.
 

·
Registered
Joined
·
763 Posts
So You've replaced the coils and sparks and still there is a re-ocurring code for a misfire in the same cylinder? Or is it just the hiccuping now? Depending on the quality of gasoline in Your area, the injectors and catalytic converter (including pre-cat) may become clogged over time. Also, get Your helpful sibling to log the intake sensors (MAF, MAP, etc) as You drive.
 

·
Registered
Joined
·
27 Posts
Discussion Starter · #5 ·
Yes, I have replaced all four spark plugs and all four coils. My brother reset the CEL after replacing the spark plugs, where it came on again a day later. He also reset the CEL after replacing the coils, where it came on again a day or two later. With each reset, the CEL appears again with the same error code. Yesterday, after my initial post, my brother and I swapped the spark plugs of cylinder 1 and cylinder 2 to eliminate the minute probability that I had replaced a faulty spark plug with a new spark plug that was also faulty. The CEL has been reset and I have little optimism that the issue will move to cylinder 1. When facing the front of the vehicle, is cylinder 2 considered to be the second cylinder from the left?

Jsilva had also questioned the injectors. Perhaps this would be the next move towards a conclusion. I will talk with my brother about the intake sensors and the acronyms you provided. Is it possible for a catalytic converter to cause a misfire in a specific cylinder?

I appreciate your time.
 

·
Registered
Joined
·
6,126 Posts
the cat doesnt control anything its the o2 sensors that see if the cat is working properly.. but the o2 sensors dont do much eather just let you know if everything is running right / rich / lean
 

·
Registered
Joined
·
27 Posts
Discussion Starter · #9 · (Edited)
Misfire Continues

This morning, upon leaving for work, my CEL has illuminated. I am waiting for my brother to use his diagnostic device and observe the error message(s).

Exhaust obstruction? Debris inside my exhaust? Can this cause a consistent misfire within a specific cylinder?

Do others believe the injector should be investigated? Would this have the highest probability of causing my vehicle's odd reaction to the accelerator?

EDIT: Because of the recent heat, I have been using my air conditioner. The problem appears to be more exaggerated. I am noticing the hiccup during acceleration and cruising. With regards to gasoline, I have been using 93 octane from BP for the past three years and feel it is unlikely the quality of the gasoline is responsible for this issue. Other current and past vehicles within the family have not experienced this problem.
 

·
Registered
Joined
·
6,126 Posts
Re: Misfire Continues

This morning, upon leaving for work, my CEL has illuminated. I am waiting for my brother to use his diagnostic device and observe the error message(s).

Exhaust obstruction? Debris inside my exhaust? Can this cause a consistent misfire within a specific cylinder?

Do others believe the injector should be investigated? Would this have the highest probability of causing my vehicle's odd reaction to the accelerator?

EDIT: Because of the recent heat, I have been using my air conditioner. The problem appears to be more exaggerated. I am noticing the hiccup during acceleration and cruising. With regards to gasoline, I have been using 93 octane from BP for the past three years and feel it is unlikely the quality of the gasoline is responsible for this issue. Other current and past vehicles within the family have not experienced this problem.
the AC compressor runs off the motor. and puts more stress on the motor so you will notice it more... i still think its an injector.
 

·
Registered
Joined
·
27 Posts
Discussion Starter · #11 ·
Re: Misfire Continues

the AC compressor runs off the motor. and puts more stress on the motor so you will notice it more... i still think its an injector.
I will discuss the injector idea with my brother. Do you know if an injector replacement can be done under the hood in the driveway? Does it require putting my car on a lift? Does the installation require any kind of configuration?
 

·
Registered
Joined
·
6,126 Posts
Re: Misfire Continues

I will discuss the injector idea with my brother. Do you know if an injector replacement can be done under the hood in the driveway? Does it require putting my car on a lift? Does the installation require any kind of configuration?
its under the intake manifold so you have to take it off. but heres some pictures and you can do it in a driveway with no jacks

http://www.golfmkv.com/forums/showthread.php?t=84318
 

·
Registered
Joined
·
27 Posts
Discussion Starter · #14 ·
Re: Misfire Continues

Will it be necessary to replace the manifold gaskets if I am going to replace the injector?
 

·
Registered
Joined
·
27 Posts
Discussion Starter · #15 ·
Re: Misfire Continues

To provide the latest information available, I wish to notify everyone I purchased and obtained a new injector along with a new intake manifold gasket. I will provide additional updates after the installation.
 

·
Registered
Joined
·
6,126 Posts
Re: Misfire Continues

Will it be necessary to replace the manifold gaskets if I am going to replace the injector?
anytime you remove something that has a gasket its best to buy a brand new gasket or a gasket silicone and make a new one.
 

·
Registered
Joined
·
27 Posts
Discussion Starter · #17 ·
Re: Misfire Continues

My brother mentioned doing the installation with me tomorrow (Tuesday, 6/14). I will be sure to update the results.
 

·
Registered
Joined
·
27 Posts
Discussion Starter · #19 ·
Re: Misfire Continues

My brother and I made an attempt to replace the injector but realized we did not have the proper tools. Does anyone know the list of tools necessary to successfully remove and install the intake manifold on the GTI MkV?
 
1 - 20 of 32 Posts
Top