Mechanic Struggling
 

Recently my 2000 Porsche Boxster began leaking coolant. I did some research on this forum and found out my water pump needed to be replaced. I'm not much of a gear head so I took it in to a local mechanic who claimed to be foreign car "experts". The mechanic told me the water pump needed to be replaced alongside the thermostat. It seemed pretty steep so I asked them if this meant that the check engine light would be gone after the work was done. He said he didn't do a full diagnostic and would do one and get back to me to see all the repairs my car needed to remove the check engine light. Turns out my car was returning an emissions code and that it also needed a new canister shut off valve. He said the total would be 1400 dollars. I agreed since i needed my car to pass inspection soon.

Got my car back in two days and the same day i received it the check engine light turned on. Took it back to them they said they were receiving the same error code (some emissions code) and they said the shut off valve they installed most likely was faulty and would replace it free of charge.

Got a call from them stating that the canister shut off valve they installed was perfectly fine. So then he said the fuel tank venting fan needed to be fixed. I got kinda upset and asked how this didn't pop up when he did the diagnostic test. He went on with some metaphor on how its like a garden hose with holes, and if you patch one up other problems might pop up. All in all he agreed to put the fuel tank valve free of labor cost but i would still have to pay for the part. So then i dished out $195 more dollars to him.

Got my car recently and after driving 25 miles the check engine light popped up. And i don't know what my next move should be. Is the mechanic telling me the truth when it comes to the garden hose metaphor? I find it hard to believe an "expert"cant fix my car in two tries.

My car has this low, hollow, whistling sound coming from the passenger side of the car and think that's probably whats causing the check engine light.

Thanks in advance for the help

It would help to know the exact code numbers that triggered the CEL's.

That "coke bottle" sound is coming from your fuel filler door area. This has been discussed numerous times here on the forum.
A CEL can be triggered by many things. You can find lots of answers here but we really need to know the exact codes that were thrown. A "foreign car specialist" may or may not have the proper equipment to properly read all the codes and information put out by a Porsche computer. I suggest that you find an indy that does a lot of Porsche work.
BTW, welcome to the forum!

Thank you both for the quick reply, I'm pretty sure the code was P0446. He told me he was getting that code before and after he replaced the canister shut off valve. So i don't understand how he came up with that i needed a new fuel tank valve after replacing the canister shut off valve.

The second reply has a pdf attached that walks you through the trouble shoot for your code. Compare that to what you already know.

http://www.renntech.org/forums/topic/36978-code-p0446/

Boxsters/Porsche's can be sensitive. Ideally you need a mechanic that knows Boxster's intimately, not a generic foreign car mechanic. If your mechanic is using metaphors, perhaps they should be teaching English instead.

Regarding your WP X/O. Do you know if your mechanic used the right antifreeze to refill your system? Porsche antifreeze is $35.00/gal and should be mixed 50/50 with distilled water. Your system holds +/-6 gallons. Mixing Porsche fluid with something generic from the parts store can cause gelling and overheating.

+1 on finding a mechanic that actually knows Porsche Cars and works on them regularly

Do you know what exact water pump he installed? Hopefully it was not some autozone/napa special with a metal impeller. Lots of threads on water pumps. In short, a metal impeller while is sounds like it would be better as it wouldn't break up into little pieces is a problem because if the bearing wears and you get any wobble in the shaft, it will act like a grinder to your engine block. Best bet is a Pierburg WP which makes them for Porsche and is an identical part

Rex is correct on the coolant. If different types of coolant are mixed, it can cause a lot of problems. $35 is really cheap for Porsche coolant, most likely around $40-50 a gal.
If the WP and thermostat were replaced, they should have also flushed and refilled the coolant

See if this is the sound you hear.
Replacing Your 996 Fuel Line Vent Valve / Bleeder Valve - Porsche 911 Carrera & 986 Boxster - Porsche 996 Carrera (1998-2005) - Pelican Parts Technical Article

The mechanic said he used OEM parts and said he would drain and refill the car with the proper coolant solution. Which is great. I've been doing research on the howling noise and found this thread that points out that I most likely need a new carbon control valve

http://www.renntech.org/forums/topic/6332-howling-from-fuel-vent/

I guess my next question is what i should do with the mechanic. I feel like he should've been able to figure out what my car needed, especially after two tries. I guess what I'm asking is should I demand that he fixes my car without me paying for the carbon control valve. He did promise me the CEL would be off after the first payment i made (1400) . I'm just frustrated because I wanted all of these little payments I'm making to be on one bill and given at the start. Is that a ridiculous demand to make?

JPDAL,
Any time and money spent with a generic mechanic is wasted or worse imho.
Just ask here for a recommendation to a specialist in your part of Tx.

The mechanic is doing the best that he can and is probably being honest, but the bottom line is that he doesn't know Boxster's very well.

A check engine light and its associated failure code only describe what general subsystem is out of tolerance or may have failed. It does not tell the mechanic exactly what part to replace. In other words, do not confuse a CEL or code with a true diagnostic test.

It is pretty common for non-expert mechanics and backyard DIY'ers (like myself!!) to replace several parts in order to solve a single CEL. This is often called "throwing parts at the problem until its fixed".

I often do this on my own and accept it because it is often still cheaper for me to replace 2-3 parts rather than pay the labor cost for a proper diagnostic and part markup that a shop will charge.

However, most customers won't accept this approach from a professional mechanic because the reason you're paying the high labor cost is to get someone who should know how to perform a proper diagnostic to determine exactly which part failed and is causing the CEL.

With all of that being said, I don't think that you're mechanic is cheating you; but you would be better served by using an experienced Porsche mechanic.

I totally agree with thstone comment. Your mechanic is just not familiar with the Boxster or Porsche and does not have the proper diagnostic equipment needed to troubleshoot your issue. I went through the issues you're going through about 6 months ago. The 1st shop I brought it to was a independent Porsche repair shop. I asked the to see if they can find the leak but no luck. I tried to avoid the dealer. I then took the car to a shop that specializes in smog issues. He owns a Smog Test only shop and a repair shop next door to it. I asked him to do a smoke test and try to pinpoint the issue. He had the car for a while afternoon and could not find the leak. Lucky for me he was honest and admitted he just didn't have the proper tools to diagnose and did not charge me a any labor. He recommended for me to take it to the dealer which I did.

The dealer ended up identifying and changing three components of the Evan system. To me the dealer was being cautious and did all three and I told them that I felt they were guessing. But in their defense they were probably right in saying that the age of the car the other components is likely to fail in a short period after leaving the shop. I went ahead and had them replace all three components.

Foreign car experts are not the same as porsche car experts. Your "expert" in quotes says it all. Run.