First of all, thank you for taking a sec to stop and read the thread. Any and all input will be greatly appreciated. In the back ground story, I have a 2001 1.8T that I gave to my g/f to drive as her daily. The tags expire at end of October, so I told her I will need to take it for a couple days to get inspection and emissions work done. She decided to wait till now to let me know it had a CEL on. I took it to Autozone to get a quick scan and ended up with 4 total codes.. P0411, P0300, P0301, P0171. Mind you I deal with investment banking as a job but enjoy tinkering with cars and have for years, though I am no mechanic. Anyways, I did my basic online research and at this point am narrowing my field to being a vacuum issue. I pulled out air box and checked all vacuum lines I can see. Shy of getting a smoke test done, I don't see any issues in lines. My next thought was to test EGR(Kombi Valve) to see if the plunger is stuck as well as replace the PCV. I just wanted to see before I dump cash I don't really have right now, into this issue, if I am going in the right direction or if anyone has ever seen all of these codes pull for a diff reason? Any advise?
Multiple CEL Codes
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You may have several issues going on. The P0411 code is for the secondary air system. That could have a leak or the pump could be having problems: 16795/P0411/001041 - Ross-Tech Wiki
The p0300 and p0301 deal with misfires. Could need some new coil packs or spark plugs.
The p0171 could be the MAF.
Is the car running poorly at all? Also, mileage?
The p0300 and p0301 deal with misfires. Could need some new coil packs or spark plugs.
The p0171 could be the MAF.
Is the car running poorly at all? Also, mileage?
Slow down a bit here.
1. P0411, a VERY common problem on the 1.8t cars is the corrugated pipe from the air pump cracks/breaks about 3-4 inches from the Kombi valve on the rear drivers side of the engine. The stupid pipe is expensive. if you remove the pipe, squeeze clips and 1 support near the PS reservoir, you can remove the entire SAP output pipe and find the crack. A few careful wraps of duct tape will likely last 1-2 years and save you about $50.
2. P0171 means you are lean and have a vacuum leak. Very common problems on these 1.8t engines are the small black and white plastic check valves on top of the engine, under the engine cover. The white plastic becomes brittle and just falls apart. The check valves vary in price, but they are available from a lot of sources.
Do not pay this much for them, but this is what they look like - Volkswagen New Beetle 1.8T Search SiteSearch Check Valve ES#3022 Check Valve - Priced Each - 058905291K
You can probably get them for $10 or less if you shop them around.
3. Misfires, turbo motors are hard on spark plugs due to the high combustion chamber pressures. If the plugs have not been changed, I would change them. But the lean condition is also probably part of your misfire problem. I would not change the MAF, this is way expensive and you can get into trouble, you have a intake and/or crankcase air leaks causing problems. Also check your orange dipstick tube, this probably needs to be replaced, it will be broken on the bottom, by this time your engine should be on dipstick tube #3 or #4. You can get these cheap from NAPA Auto Parts for under $8 typically. The probably also have the check valves.
Given you need to get the car through inspection, suggest you purchase your own OBDII scan tool. For as little as $30 you can have something useful. See the OBD link below in my signature.
1. P0411, a VERY common problem on the 1.8t cars is the corrugated pipe from the air pump cracks/breaks about 3-4 inches from the Kombi valve on the rear drivers side of the engine. The stupid pipe is expensive. if you remove the pipe, squeeze clips and 1 support near the PS reservoir, you can remove the entire SAP output pipe and find the crack. A few careful wraps of duct tape will likely last 1-2 years and save you about $50.
2. P0171 means you are lean and have a vacuum leak. Very common problems on these 1.8t engines are the small black and white plastic check valves on top of the engine, under the engine cover. The white plastic becomes brittle and just falls apart. The check valves vary in price, but they are available from a lot of sources.
Do not pay this much for them, but this is what they look like - Volkswagen New Beetle 1.8T Search SiteSearch Check Valve ES#3022 Check Valve - Priced Each - 058905291K
You can probably get them for $10 or less if you shop them around.
3. Misfires, turbo motors are hard on spark plugs due to the high combustion chamber pressures. If the plugs have not been changed, I would change them. But the lean condition is also probably part of your misfire problem. I would not change the MAF, this is way expensive and you can get into trouble, you have a intake and/or crankcase air leaks causing problems. Also check your orange dipstick tube, this probably needs to be replaced, it will be broken on the bottom, by this time your engine should be on dipstick tube #3 or #4. You can get these cheap from NAPA Auto Parts for under $8 typically. The probably also have the check valves.
Given you need to get the car through inspection, suggest you purchase your own OBDII scan tool. For as little as $30 you can have something useful. See the OBD link below in my signature.
Awesome replies guys, very helpful information. I was putting EGR back in car after pulling it to see how corroded it looked and saw the vacuum line going into back side was dry rotted on the end. There was plenty of slack so I cut about 1-2" back where is was solid and reconnected it. Reconnected battery. Car had a an odd minor idol surge (750-900) for a few moments, engine shook like it was wanting to shut off, but then it evened out. Drove car on highway about 25 miles to see if CEL would re-appear. Got home and just as I was thinking "that was easier then I had first thought"....BOOM!! CEL back on. I did used to own a cheap little scanner but somewhere in all my moving it vanished. I need to get a new one.
Again, thank you guys for your help.
Sorry, should have stated that in the beginning. G/F drives it, said it idols rough in the mornings when it cold but other then that, runs great. I drove it around last two days and it is smooth running. Car just turned over 100K. All routine maintenance done on time.
I didn't notice any issue with them on my first inspection of vacuum hoses but I will double check as my focus was not on them.
My thought exactly since I was getting multiple misfires. The P0301 showing a misfire on an specific cylinder threw me though. To test this I will swap the coil pack from cylinder 2 into cylinder 1 and retest it, the code should follow to cylinder 2 and cylinder 1 should be ok? The plugs are fairly new... i would say maybe 5 months old, and about 4k miles. I can pull them to check how they look.
That's a new one to me... I'll take a look at that as well.
Again, thank you guys for your help.
Do not worry about the spark plugs if they are fairly new, not sure I would even worry with moving coils around. The misfires are probably due to cold start misfires because of a lean condition.
Until you can read the fuel trim and figure out if the misfires are at idle or cruise, I would not worry too much.
Be careful about the scan tool you choose, you want Emission Readiness Monitors, Freeze Frame and Real Time data.
Until you can read the fuel trim and figure out if the misfires are at idle or cruise, I would not worry too much.
Be careful about the scan tool you choose, you want Emission Readiness Monitors, Freeze Frame and Real Time data.
I went with an Innova 3100 scan tool. Not the best brand but I have heard good things about this one from online and I was able to get it for a reasonable price. Double edged sword, I know.
WINNER WINNER, CHICKEN DINNER... Not saying its the end all cause of my problems and I won't know till I can get it scanned again, but I did find one. Hovering just over my #3 coil pack, I found a check valve with a broken(black part that overlaps the white) side and what appears to be a similar corrosion(only at the broken spot) as you might find around a battery terminal. Now the question is, can I just replace that with a universal Vacuum check valve like you would find in the HELP! section of most any auto parts store or do I need to specifically buy MFG part# 058905291K?
Ran out of light today and still need to wait on scanner to arrive so gives me a day to pick up some parts if needed. Oh and I did check the oil dip stick as advised and it appears in fantastic shape. No cracks or breaks.
The codes will clear themselves if you get the problem resolved after a certain number of start cycles.
And it is the dipstick tube, not the dipstick that is the problem. It is the base of the orange plastic tube that breaks where it transitions to the metal pipe.
And it is the dipstick tube, not the dipstick that is the problem. It is the base of the orange plastic tube that breaks where it transitions to the metal pipe.
I have a 2001 1.8T. I had several instances were the Check Engine light came on steady. Codes P0171 & P0174 are detecting lean fuel condition - meaning there is not enough fuel in the air/fuel mixture. P0411 is an additional indication down stream basically saying the same thing. These codes mean you either have a fuel delivery problem (not enough fuel) or you may have a vacuum problem causing too much air. Faulty O2 sensors and MAF units may also give you this code. I replaced my fuel pump - no more check engine light and codes are gone.
Sorry, I should have been more clear on that. I got what you meant in the original posting. Its clean as a whistle shy of some small traces of grime but after wiping it down, its G2G
Thanks for the update, however before I dump more $$$ into it blindly I am waiting on my scanner so i can test all my possibilities. I should have it in by Friday at the latest. I used to just fly an old friend out to test and tune my cars with my AEM on a stand alone mod., but those days are long over.
Not sure if you still understand what I was saying?
The orange plastic dipstick tube breaks down due to the engine heat at the very bottom of the orange tube. Then the tube cracks where it interfaces with the metal stub tube in the engine.
I have never seen an orignal tube on these cars that is not broken.
You indicate it is clean as a whistle, nothing to do if it is clean or not, it cracks and then does not seal with the metal stub pipe. Very hard to see and tell unless you know what to look for.
Maybe your tube is fine, you will have to verify.
New tube from NAPA is only about $4.
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