99 VW Beetle ProblemS

1999 Volkswagen Beetle 4 cyl Two Wheel Drive Manual 161000 miles

Hello! I have 99 VW beetle with a 2.0 4 cylinder engine with little over 160,000 miles on it. I was driving down the highway, all the sudden the car lost at least 50% of power and got really loud under the car and the CEL kicked on, I took it to a mechanic, they he found a hole in the exhaust pipe behind the Catalytic converter with a chunk of CAT material in it, they fixed the pipe, but we didn’t replace the CAT at that point, because we didn’t think it was a big deal. The car continues to run poopy, CEL light stayed on, car misfire and bucked and hesitate when accelerate and once in a while there is a stinky smell coming into the cabin, not sure what it is either . Took it to autozone, ran a scan, and they said all four cylinder misfire and recommend a tune up, so we did, but it runs the same. So I finally took the car in to change the catalytic converter, and they switched off the CEL light and the misfireings are now gone. But the same day I got the car back from them, the light turned on again Autozone read Faulty MAF, IAC valve. Code P0102,P0134,P1582,P0506. The day before all this happened, I ran the tank real low on gas, but I made it to the gas station and filled it back up, and it ran just fine. Then a day or two later all these things happened.

Now after tune-up and CAT changed, car runs go until it gets warm, and it seems like it lose some power and a rattle noise is coming from the bottom of the car again, and I believe is the new CAT getting burn again.

VW parts are expensive, and I don’t have any extra money I can spend on the car!


First, that post is really confusing - paragraphs are really a help. To much information packed in to too small a space. Your eyes start swimming just looking at it.

Second, I have to wonder whether or not you have really maintained the car well over the years - and “regular oil changes” doesn’t count. If you said something about that it might help.

Third, this recent episode with the cat is basically car abuse. I’m not sure who found a chunk of the cat in the exhaust leak, but the whole episode was screaming “clogged cat! clogged cat!” So driving around with it like that was just engine abuse.

Fourth, if you want to try to tackle today’s problems I would do two things: 1) clean and test the MAF sensor, including its power supply (P0102); 2) figure out why the front O2 sensor is not sending any signal to the PCM (P0134). If you figure that out the other two codes (both about idle control) may also be taken care of.

Fifth, has this been going to the same mechanic? Maybe you need a new one.

sorry about the last post, and thanks for the reply.

I just bought the car last December, and after drove it for a month, all these things happened.

I tried to get it back to the shop ASAP, but I just didn’t have the money. Since I got the car, I have never abused it, I switch gear every 2500 RPM, the only time it gets over 3000 RPM is when it’s on highway.

I have checked the MAF sensor, it looks crispy clean. Do you think because of the previous CAT got too hot and messed up the pre-oxygen senor?

I haven’t taken it to any mechanic other than to the shop where I got the CAT fixed and ask for their opinion on it. And like I mentioned before, I don’t have a lot of money, took me a while to save up and finally got it into the shop to fix the CAT.

NEW Questions:

  1. Do you think the low fuel triggered everything?
  2. Where is the power supply to the MAF?
  3. I went online and someone said it could be the Engine coolant temp. sensor? do you think that could be a problem even though it wasn’t one of the code?

Thanks again for all the advice!
Looking forward to hear from you again!

All of those codes suggest a wiring problem and could be as simple as a wire which has come loose; unfortunately Autozone’s scanner isn’t going to tap into VW diagnostics to give you more insight…it just can’t talk to the vehicle’s controllers. You should find someone in your area who has invested in a VAG specific analyzer such as VCDS. With that cable and it’s software they’ve got the capability that real VW/Audi technicians have. Also, spending a hundred bucks for the white Bentley repair manual is a wise investment (assuming you’re going to keep the car)…having made the investment in a new cat it sounds like you’re “All in” on keeping the Bug so invest a bit more and read it. These are well enginieered/built little cars despite all the negatives you will find on the Internet (there’s no rule that posters have to be truthful and unbiased - or even relating real stories). I think that, in addition to incompetent and outright fraudulent “mechanics”, is the majority of the problem. You should find a specialist (and you will pay for that priviledge) who can troubleshoot and give you substantial answers not some parts-changer/grease-monkey. If they use terms & jargon like “that tranny is shot” TURN AROUND AND RUN.
Being low on gas has nothing to do with your problem…