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Discussion Starter · #1 ·
Driving home in traffic and my car starts to miss fires and bogs to a complete stop during acceleration to a point where it wont go anymore. Idles fine unless I hit the accelerator. Eventually it dies altogether because I am trying to get out of traffic.

After the tow home, I changed the MAF with new one from the dealer(yes, I got reamed). After jumping the car, it idles fine, but when I hit the accelerator to give it some gas, it dies. If i try and inch in drive, it dies.

Starting the car takes a little effort but it starts.

My fuel pump is humming.
I changed the fuel injection regulator, problem doesn't go away.

Up until today, car has driven fine. Accelerated well. Idles well.

I removed the Throttle body to clean tomorrow. I can't locate anything on diagnosing with a meter. Is there a way to do this? Its the VDO type, big bolt-on sensor mechanism.

Any suggestions are welcome on what to do next.

Thanks.
 

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Stacks on deck.
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maybe advance your timing? have you heard your engine ping under acceleration in the last few weeks?
 

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check the fuel delivery system, then ignition system. one of those are at fault. rarely theres faults on sensor im my experience.
 

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Discussion Starter · #8 ·
Sorry for the late response. I've been out of the country for the better part of a week.

I disconnected the throttle body wiring harness and found that the car will drive around. It will not take a huge increase in acceleration, but a gradual one it will take. It drives fine. It does take more effort to start.

I would conclude from suggestions, that it is not a coil pack, or an ignition problem or a fuel problem.

I believe it is the Throttle body. I did clean it, but no improvement.

I do have a CEL, but dont have a code reader. I will try to get this in the next few days.

Anyone know of reliable throttle body vendor(new or refurbed)?
 

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lowness and dopeness
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Honestly man, go to a junkyard, or better yet, vwvortex.com and find someone parting out a mk3. Thats where i get all of my parts man. I dont understand how your car still drives with it unplugged lol, check thos codes man! i have a scanner, where do ya live
 

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Discussion Starter · #10 ·
Atlanta.

I just need to run it to Autozone and get it read. Ill have the codes soon.

I think it runs in limp mode just like when you disconnect the MAF and have the same affect. Lots of redundancies in the Jettas management system.
 

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Discussion Starter · #11 ·
I went to Autozone to get my codes scanned, and on the way there my CEL went off with the harness disconnected from the throttle body. The AZ employee said they could not scan if the light was not on.

I was back to square one, so I decided to replace the spark plugs, cap and rotor and my car is back to normal with everything connected as it should be. The old plugs were at a gap of >.065....worn out.

I don't understand why disconnecting the throttle body harness allowed the car to continue in limp mode, maybe it provided some retarding or advancing that gave it a little more time.

Looking at the Haynes manual troubleshooting section, for acceleration problems, the first thing you look at are the spark plugs.

Start with the basics!
 

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hey i had the same exact problem and after watching under the hood while my brother revs it i noticed the spark plug boot would send a visible spark straight to the block. only happened on the second plug from the right. i dont know whats causing it but for temporary i just put some tape arond the metal part of the boot and it runs fine. probly wont last to long lol but thats my two cents.
 

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hey i had the same exact problem and after watching under the hood while my brother revs it i noticed the spark plug boot would send a visible spark straight to the block. only happened on the second plug from the right. i dont know whats causing it but for temporary i just put some tape arond the metal part of the boot and it runs fine. probly wont last to long lol but thats my two cents.
ohh that's pretty bad way to fix that. I know a hot rod guy who was driving like that to save money and he had small leak of gas somewhere in the engine bay, out of nowhere his car caught of fire under the hood while driving due to the sparks coming out of his broke wires that reached the gas. id buy new wires if i were you pronto just for safety.
 

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ohh that's pretty bad way to fix that. I know a hot rod guy who was driving like that to save money and he had small leak of gas somewhere in the engine bay, out of nowhere his car caught of fire under the hood while driving due to the sparks coming out of his broke wires that reached the gas. id buy new wires if i were you pronto just for safety.
haha yea i know im replacing them today 90 bucks at advance auto. just long enough to get me back and forth to school for a few days
 

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Discussion Starter · #18 ·
Moderator can close out this thread. It was the spark plugs in my case. I had not replaced them in probably 3-4 years, well over 100K miles. New plugs, cap and rotor. Car hums nicely and haven't had an issue since my original post.
 

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always follow the first rule of thumb, do a tune up to terminate probable cause of major issue:rolleyes:
 
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