slaskowski

I had my 1998 993 Cabriolet worked on by a local Porsche mechanic a month ago to fix a broken shift linkage. The engine had some leaks as well which we had spoken about a year earlier. I decided to have the leaks repaired as well and since the engine was partly taken apart, they changed the ignition wires as they were the original wires ($4,000 for the entire job)

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After 50 miles on my first highway trip since the repair, the check engine light came on. I hooked up my Durametric and pulled the following codes:

107 - Supply Voltage
169 - IACV Make Winding
168 - IACV Break winding
35 - Oxygen Sensing range 1 (cylinder 4-6)

I reset the codes, re-started the engine let it idle for about 5 minutes - the codes stayed off.

Is it OK to drive the car in this condition or is it a sign of some bad stuff going on?

Any insight into why these codes would pop after such a repair above?

Any help/insight would be appreciated.
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Hi Steve,
Sounds like you've done the right things so far, also I assume you have informed the shop that did the work. I didn't look up any of your codes, but based on what I see pretty sure the 2 in the middle refer to the idle air control valve, seems like it is not plugged in (ie the supply voltage code). The oxygen sensing code is possibly related but not necessarily, the IACV code could have set it off or could be separate. Either way I don't think you will do any harm by driving it(may have trouble idling hot/cold), although if I recall that valve should be right on/under the intake or near the throttle body so you could try and locate it to see if it is plugged in... also those connectors all start to look alike, pretty sure it would have just a 2 or 3 pole connector on it and it is possible that it was connected to something incorrectly.
Oxygen sensor I would think is plugged in as those connections are pretty obvious, but if you want to check I believe they live on the left and right back side of the engine compartment in pairs. If it is plugged in then you've done all you can for now by clearing the codes and seeing if they come back.
Good luck~
J

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Thanks so much for the information, super detailed and very useful!! I just got back from my trip on Sunday and ended up taking her for a quick spin to stretch its legs. After 30 minute trip, the Check Engine Light came back on (I had reset the codes previously with my Duratech).

I checked the new codes this time and got the following code (which I had previously got before):

Motronic 5.2 M14
35: Oxygen sensing range 1
Cylinder (4-6)

Interesting that it was only the Oxygen-Sensing Range 35 code as I got the following collection of codes as well when this issue started.

107 - Supply Voltage
169 - IACV Make Winding
168 - IACV Break winding
35 - Oxygen Sensing range 1 (cylinder 4-6)

I am going to check out that the idle air control valve is plugged in properly as per your previous suggestion. I will unplug and plug it back in and they go for another ride to see if the problem returns.

Thanks - Steve


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As an update, I ended up reseating the connection to the air control valve per @JJKL's suggestion above and cleared the ODB codes.

After 40 minutes of spirited driving, the check engine light came back on. I got the following codes:

35 - Oxygen Sensing range 1 (cylinder 4-6)

I reset the codes and took it out for another run a week later. I noticed that it was idling a bit rough as well. Similar to before, after 40 minutes of highway driving the Check Engine light came back on. I pulled the ODB codes and got the same error as above

35 - Oxygen Sensing range 1 (cylinder 4-6)

I have two quick questions:

• How much should I push back on my mechanic as the codes starting showing up after he replaced the ignition wires and a number of gaskets to fix some oil leaks?
  • Was it just "bad luck" or coincidence that I am now having problems with the Oxygen Sensor?
  • Is there a chance that when he was working on the engine that he had to take out the Oxygen Sensor in order to install the gaskets and/or ignition cables and that it was not installed properly?
  • Any other ideas why this would happen after the repair (Besides bad luck/coincidence)?

I would really appreciate any insight.

Thanks - Steve

mpit

I would push back asap. The closer it happened to the rebuild the more apt it was caused by something he did. I think you stated within 50 miles. I have found that is about the time tit takes for lights to come back on after a reset. The chances of being coincidence are very low. Is this a guy you have used a lot in the past? Care to share who it is? Also how many miles are on the car?

Churchill

Please don't. This is someone's livelihood and reputation you're talking about. There is no evidence so far the mechanic did anything wrong, and even if he did, he'll probably make it right. Let's not drag people's names through the mud online unless absolutely necessary. How would you like it done to you because you made a mistake at work (or an ignorant customer was convinced you did)?

mpit

It's fairly obvious something was done wrong. It's now a question of whether or not the guy is wiling and able to stand behind his work. I had a clutch put in an 89 about 7 years ago. The mechanic recommended I do several other things to the car while it was apart, which I agreed to do. He told me ahead of time he was going to drive the car for an hour or so, after the repair, just to make sure things were done right.

It is a headache and a hassle to have to take a car back after a major repair because the work was not done properly. If this guy would have taken the time to do this he would have caught the problem. Strike one.

Churchill

It is not the least bit clear what is wrong or why. He has an O2 sensor code. O2 sensors go bad, happens all the time. Even if it was because of something the mechanic did, there is still no reason to publicly attack him. Working on old cars is not a laboratory science and even the best mechanics make mistakes or miss something. What do you do for a living mpit? Can we apply to the position you're staking out here to you?

JPS

Let him know absolutely.

I will say the innards of these cars are starting to be tomb like in some ways. Undisturbed everything is fine, but if you start to move things around, other bits unrelated get disturbed too.

It may be related, it may be a coincidence, but I agree. Assume all will be a done right until proven otherwise.

mpit

I spent 21 plus years in the car business.. I dealt with mostly foreign cars.. I sold Toyotas in Lansing Mi for 15 years. I averaged 23 cars per month. I was a member of Toyota sales society for most of these years which means I was in the top 1% in the nation. A lot of my business was referrals. I did a pretty good job. You get referrals when you do a good thorough job, the first time around. Often times when a customer brought a car back for service I would go drive the car when it was done, just to make sure things were done right. From time to time they weren't. BeBacks are good when your selling. Not so good when your fixing.

If your spending 4 grand on a repair bill, probably 2 grand is for labor. which could equate to 16 hours of work. If this guy would have spent another 45 minutes driving the car after he thought he was done, he could have prevented a comeback. Comebacks cost both time and money.

Hopefully the guy will fix what was not done right in a timely fashion and get the car back on the road. He might deny any culpability. and hit the poster with another large repair bill. Reputations are made on how they handle problems. Considering so many codes are popping up it appears like several things were not done right.

pp000830

[107 - Supply Voltage - probably tripped when the battery was disconnected, unlikely to come back
169 - IACV Make Winding - /168 - IACV Break winding: Should not come back, if it does unplug the idle control valve hose out the plug and socket with spray electronic cleaner and reseat the plug making sure it fully seats and its sealing gasket is laying flat.,

35 - Oxygen Sensing range 1 (cylinder 4-6);
Short to Ground / Below Lower Limit / Lean Mixture Limit OR
Short to B+ / Above Upper Limit/ Rich Mixture Limit
If the code returns check the oxygen sensors' slide connector in the little triangular box on the passenger wall of the engine compartment to verify the sensors are properly plugged in with the grey plug in the grey socket and the black plug in the black socket. If you don't have Durametric to look at oxygen sensor data I would just replace the sensor listed as it is a < $100 part and is a really easy DIY replacement.

If your engine was moved the wire to the oxygen sensors is easily damaged as it includes a very small gauge breather tube in it needed for the sensor to work properly. If the wire gets twisted, pinched or folded the breather tube can get closed off causing the sensor to not work properly. Do not use an electrical cleaner on the oxygen sensor pigtail plug as you run the risk of contaminating the breather tube.

The easiest way to replace a sensor is to put a little penetrating oil on its threads, let it sit overnight, cut the wires to it close to the sensor body, slip a closed end box wrench over it and break it free. Once the new sensor is screwed into place tape the new sensor's wire to the old wire and use the old wire like a fish-tape to thread the new wire up into position. You will need to reinstall a body grommet in the sheet metal above the sensor, no hard to do.
By screwing the new sensor into its bung before wiring it one can avoid twisting the wire putting undue stress on the pigtail's breather tube and causing the new sensor to have functional problems.
Andy

mpit

If I just paid a guy $4,000 to fix my car and it didn't last 50 miles. I am taking it back!

Churchill

i wasn't suggesting OP shouldn't take his car back if the repair was incomplete or unsuccessful. I was saying that dragging the mechanic's name through the mud in a public forum when OP doesn't even know if he made a mistake is a big-time a-hole move.

mpit

. I didn't mean to suggest he should throw the guy under the bus. I just asked if he cared to share who it was. Maybe he's used the guy many times in the past and always had good luck with him. Maybe this is his first time using the guy. If so I'd be a little leery about using him in the future.

If I pay 4K to fix a car and it isn't right, I am not a happy camper. This is a time when the guy should step up to the plate. You fix the car, quickly an get it back on the road. You also give them a reason to come back. Detail the car, your next oil change is on me, here's a couple of tickets to the Pistons game. something to show you care.

The internet can be a powerful tool especially with high end foreign cars. There is a big import dealer in New York who found that out the hard way.

Viperbob1

As a shop owner I can tell you coincidences happen ALL the time. Had a customer drop a 996 Cab off for service the next day. It stayed where he parked it and when we went to move it inside the rear window had fallen out of the convertible top where it was in 2 hours earlier when we did inspection of car. Immediately called customer and of course he wants us to buy a whole new top because we ruined it. I have about 50 other examples. You are in this business long enough and you will see them far too often.

That being said, I would politely take the car back and explain what you saw and how the SAI was not plugged in properly. As an owner I would want to know that. And have them look at 02 sensor. If they did not remove it out of the pipe, and the connector is good and connection solid it is just bad. Get a new one. I know it is always easy to blame the shop, but many times stuff just happens.

slaskowski

Thanks for all the information!!

BTW - I was/am not going to publically shame the guy, in fact, I purposely did not mention his name. I actually like the guy and have a good relationship with him (at least I like to think so).

Just wanted to know how much I should push back with him 1-1 in my discussion with him on the upcoming bill

Endoman

I just get my hands dirty and avoid the bills. I wear gloves at work anyway

Gbos1