Volkswagen Jetta Junkies banner

2002 1.8T Jetta -- Codes P0300, P0171, P0301, P0303

3111 Views 8 Replies 4 Participants Last post by  JakeM35
Hi all,

I have a 2002 vw 1.8 turbo jetta with 190,000.

My car was doing fairly good until I added some of gas treatment stuff (I think STP). Since then, it has been a lot louder and sounds like its misfiring. And the engine light came on.

The STP gas treatment may or may not done it ... IDK

I took it to my local advance auto and had then read the codes. They said I needed ignition coils. So, I bought them, replaced all 4 of them, and reset my battery. The engine light stayed but it still sounded the same. After 2 days the engine light came on again, and now they have a completely new set of codes of the following.

P0300- Random - multi misfire
P0171- Bank 1 system too lean at idle
P0301- cy1 misfire
P0303- cy3 misfire
-I also believe an upstream o2 sensors also.

Any insight would be helpful.

Thanks
1 - 9 of 9 Posts
sounds like the fuel treatment is doing more harm than good, how full of a tank do you have? when was the last time you changed the fuel filter?
sounds like the fuel treatment is doing more harm than good, how full of a tank do you have? when was the last time you changed the fuel filter?
hmmmm. I really can't remember the time I changed it. I need to youtube it and see if its a easy repair.
hmmmm. I really can't remember the time I changed it. I need to youtube it and see if its a easy repair.
the fuel filter can be an easy thing to do however, every mk4 I've seen fuel filters done on and ones I have done the clips break for the fuel filter, they just get old and with all the dirt and grime the clips break easily and then require either fuel line repair or replacement
Just found a busted hose on the PCV valve ... probably causing a lot of the issues! Gonna look for hoses tonight.

Attachments

See less See more
That hose breaks all the time it happened on both of my 1.8's the dealer should have it in stock its normally around $30 bucks... Also this should be a lesson to not trust
autozone employees
The dealership quoted me $1600 to replace the entire PCV system ... I'm not a cussing man, but I almost cussed at him.

Today is first day driving it. It started off still sounding rough. But after it got warmed up (maybe 5 minutes), it drove great. Idled great with no misfires. Will see how it drives tomorrow and if the light stays off (I reset the checking engine light by disconnecting the battery while working on the hose).
Check NAPA since they usually have parts in stock or find someone else that specializes in European vehicles if you're not mechanically inclined or don't feel like doing the job.

The dealership would be the last place I would bring my vehicle, especially with the labor rates being pretty high.

Here's the part you need.
http://www.germanautoparts.com/productdisplay/70633
The dealer is a little crazy with labor prices if your'e relatively handy you could replace that hose yourself with minimal effort and a couple screwdrivers the part itself has an msrp of $45.00
1 - 9 of 9 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top