Is it for sure the Catalytic Converter?

I have had an issue with my 95 Jetta that is quite honestly driving me crazy. I will give you as much history as possible and god bless anyone that can really help me.

I bought the car a few years ago. It ran fine when I bought it. When it is started, about 20 or so minutes in I will see the engine light come on. It has done this since day one. Gradually over time I have noticed that the car runs fine when the light is off but as soon as that light comes in the performance goes down the tubes. It bogs down heavily and sort of sputters. However once that light goes back off the performance returns right back to fine.

So I take the car into the dealer and they tell me that it is a timing issue and they will look into it. THey call me up and say the timing belt needs to be replaced. I did argue with the guy for a bit as the fix didnt match the issues in my opinion....either way I went ahead and got the belt replaced. I get my car back...same thing. 4 visits and $600 later the car is still not working.

The car is in a state now that the light is on 80% of the time and it dies now. From time to time it will snuff out completely when I go to push on the pedal. However as soon as I stop the car it will run fine again.

SO I have been told it is the catalytic converter....and from any posts I have looked at that address issues with catalytic converter on this car on this year the issue match almost to the T.

What does anyone who knows more than me about this car (which will be almost all of you) have any insight on this?

Things to note: It has a brand new rotor, cap, plugs, plug wires, and fuel pump. The timing is correct and as far as I know, the distributor does not need to be replaced...even though the dealership mentioned that as a fix...but after the assistance I have got from them I am going to take my chances on the net.

Reply to
G-Ram
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"G-Ram" wrote

Obviously, since the check engine light goes on, you need to look at a menu of what the computer recognizes in the engine for the light to come on and look at the most feasable possibilities. Are you sure this couldn't be something as simple as a bad or bad ignition wire that works intermittently. Perhaps when it is running at it's worst it may (don't know from the little you wrote) be running on 3 cylinders? (or even 2) Have you changed your ignition wires? I had a Golf that ran terrible that was simply due to a failed and intermittent ignition wire to cylinder 4.

You may have blown your catalytic converter because the engine may have been driven with fuel going through it from the bad running, combusted in the catalytic converter and fried it. That is the only link I see to your catalytic converter.

If you have on your service order your problem of "engine light coming on", charging you all that money and not fixing it-I would demand either they fix it since they misdiagnozed it or your money back. Personally, I would not let them get away with it even if I filed a small claims court claim. Since the engine ran fine at times, this had NOTHING to do with the timing belt, for instance skipping or jumping a cog. It would run ALL the time poorly like that, if it were possibly the timing belt.

In my opinion, the catalytic converter is collateral damage and not related to the problem. It very well need replacement though.

Harry

Reply to
Harry

I agree with Harry, but I am interested in "I have been told it is the catalytic converter." Who told you and what did they form that opinion on?

Reply to
Joseph Meehan

You must be the fourth or fifth poster that's had the same problem. I had exactly the same issue with my 1995 Jetta GLS. It started with the engine light going on then off, accompanied by stuttering and piss poor performance. As soon as the light went off, performance returned. I tried changing the distributor cap and rotor, cleaning the throttle plate, replacing the plug wires, and overal there was 0% improvement. If fact, it got worse to the point where the check engine light was on 100% of the time.

The engine kept running crappily, but then I started hearing a rattling sound coming from the exhaust system, after driving it for 16 months or so with the above stated poor performance. It turned out that one or more of the screens in the catalytic converter had broken off and was essentially blocking exhaust flow. This may have been caused by the distributor which it turns out was the cause of the check engine light coming on, then off, then permanently on.

My diagnosis to you? Have the distributor and catalytic converter replaced. Don't buy the dealer recommend catalytic converter because they will charge you $1200 to $1400 and its complete theft. Order a replacement Techtonics catalytic converter from Rapid Parts, have the dealer or your mechanic install it (and a new distributor) and you should be back in the running. Total bill with labor, around $800. If you do it all yourself, then maybe $400 to $500.

One interesting point about the distributor, apparently the Hall Effect sensor that measures/senses engine rotation speed fails quite often on these things, but since its an integral component, you can't just replace the sensor, but you have to buy and install the entire distributor. The sensor is probably $0.25 of electronic/magnetic components, but you'll still need to buy the entire distributor for $180 or whatever they cost now.

PS: I think your timing belt was okay, but now you don't have to worry about that, right?

Reply to
PabloRena ---> AnalProbe

How is your oil pressure? Low oil pressure could be a sign of bad main bearings. Any unusual engine noises? How many miles on your car?

Reply to
Papa

Incredible -- you've just perfectly described what's been going on with my Jetta. Engine light on and off (for about a year), then full on (for about three or four months), followed by rattling from the exhaust system (began about a week ago), now the engine stumbles from idle (first noticed it yesterday). I was figuring a loose heat shield on the catcon, but your description is eerily accurate.

The engine code reader had said "high voltage reading from the coolant temp sensor," and since it wasn't overheating, I let it go. I suppose I'll pay the high price now for ignoring the warning.

Reply to
Brian Running

I will share my fix with you when and if it every happens.;)

Reply to
G-Ram

fix...but after the assistance I have got from them I am

Sounds like what happened to me and it was the 02 sensor.

Reply to
Dave

"Brian Running" wrote

If it isn't catalytic converter breakage causing blocking be prepared to buy yet another cat if you run it long as the poor running will destroy the new one too. By process of elimination everything else should be tried or eliminated first

If I thought this, since the cat is most likely destoryed anyway and you are going to replace it anyway, having the tools to do it - before I would install replacement cat - I would cut the existing cat open with an air cutter - removing the heat shield - a flap bending the flap open cut into the cat- remove any broken parts if any - and mig weld it back shut cleared of blocking fragments - (an alternative to this though would leak but would tell the answer would be to pop rivet some sheet metal over the access hole after removing fragments - it only needs to be run a few minutes to give the answer) - run the car again for short period since it has no cat effect. If the car now runs correctly - simple fix of replacing the cat - if it still runs poorly - you saved yourself another cat expense by damaging a new cat - unless you had it immediately repaired, finding the new cat did not fix it. . It should be replaced anyway. Cats can be fairly inexpensive if you do the work yourself. I don't use name brands. On an A2 I just put in a Golf a cat/front pipe (cat welded on front downpipe) that cost 97 dollars (Maremont) it passed inspection with flying colors.

Harry

Reply to
Tony

I am simply amazed that you are the first person to mention the most obvious culprit.... at least to check or replace 1st.

Reply to
mr nobody

Reply to
G-Ram

One thing to do is to disconnect it, and see if the car runs better.

Reply to
Tom's VR6

"Tom's VR6" wrote

Not to be posting all over this newsgroup: There is some major common sense and a stupidly simple test.

I had a Golf A2 once that ran great for the a couple of minutes then ran terrible, puffing smoke after that and missing. It ran so bad that it was undrivable. It WAS the O2 sensor and it also was a real son of a B to remove because the anti-seizing compound did not work too well. It took great effort to remove it. I had to weld a special bar up to remove it. I put in a generic O2 sensor that cost about 20 bucks from a discount parts dealer

Ran perfect after that.

If the cat were blocking exhaust flow it should be noticable out the back exhaust feeling the restriction. If it is blowing freely it is not restricted. It is probably toast though, like I said before and very well will fail emission inspection from running a badly running engine through it for so long.

Harry

Reply to
Harry

OK EVERYONE!!!!

I have been informed by my mechanic that the reason for all of these problems I am having is because the Hall Generator is bad and needs to be replaced. My entire exhaust system is fine (thank god) everything else is fine too.

Maybe a discussion on what the hell a Hall Generator is and what function it performs is in order...

Thanks to everyone who replied with ideas and assistance.....

Reply to
G-Ram

It's inside the distributor. It's like points in them old cars.

Reply to
Woodchuck

Here you are, from Microswitch:

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Reply to
John H

pulse generator that makes use of the Hall effect and consists of a rotor with vanes, a conductive element with a permanent magnet and the Hall IC. Also called "Hall element."

AND

transistorized ignition with Hall generator: (TI-H) There are two types of TI-H: in one version, the dwell angle is determined by the width of the rotor vanes in the distributor; the other version contains a circuit for automatic dwell angle control incorporated in the electronic control unit

Reply to
Dave

In addition to the other info, its main function is to tell the engine computer when to fire the spark.

Reply to
Tom's VR6

"G-Ram" wrote

I would have a serious issue with the shop that charged me over 500 dollars saying the problem was a timing belt that was nonsense.. The material thing is what was written on your service order. If it promised to fix the 'engine needs service' light and that was written as the problem you may have grounds for reinbursement - though I doubt they will happily go that way. Probably more to it and I am jumping to conclusions like the service was performed too long ago.

Harry

Reply to
Harry

Did he say that the Hall Effect sensor can be replaced itself, or does he need to replace the entire distributor?

I don't know why he's calling it a "Hall Generator" when its actually a sensor. To quote from my handy dandy "Electronic Engineer's Handbook, 3'rd Edition", page 6-88., "A magnetic field applied across a current-carrying material will force the moving carriers to crowd to one side of the conductor. An electric current will develop as a result of this crowding...". I believe that when the distributor is rotating, some portion of it must be magnetized and this spinning magnetic field crosses the Hall Effect sensor. The output of the sensor is a series of electric pulses that are conditioned (filtered and level adjusted with operational amplifiers) and interpreted by the engine controller to adjust timing.

Anyone, tell me if I've got this wrong. As I told the orignal poster back on 7/12/05, I knew it was either the distributor or the catalytic converter, I just didn't know which one. Unfortunately on my car both systems had to be replaced at the same time.

Reply to
PabloRena ---> AnalProbe

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