So I finally got fed up with Goodyear and decided to take my Volvo XC70 2004 elsewhere. Goodyear said put their Master Mechanic on the problem I think they caused and said they want to keep the car further (they've had it 5 days for what was originally new tires and an oil change) to keep checking it out. I had it at that point and told them I wanted to take it elsewhere (I always take it to Autobahn in Copley, OH, but didn't this time because I needed new tires). I told them I wanted them to pay for it. He put me on hold for while and came back and said they would pay the bill elsewhere for diagnostics and if it was something stupid that they had done, but wouldn't pick up the bill for something random that happened while it was in their possession. Anyway, I picked it up and drove it to Autobahn, here's what's happening. Autobahn can't look at it for a couple of days due to volume so I'm still trying to see if I can figure out anything on my own. The car drives fine with normal power and runs great while accelerating and cruising and coasting while moving. However, when at a stoplight with the brakes on it loses power (though the rpm's don't sag) it seems like it wants to stall but doesn't stall. I kept it in Drive, put it in Neutral, put it in Geartronic while stopped and it's all the same thing. While in Neutral I gave it a little gas and it seemed like it was good but when I took my foot off the gas same loss of power feeling. It seems to lose power then almost seems like it wants to take off over and over while braking, but of course I have my foot on the brake so it can't take off. When the light turns green I start driving and it goes great and smooth and normal power until I have to brake to a stop again then same thing. Anyone have a feel for what this could be? Thanks for everyone's input, I really appreciate it!

 

Oh and the Check Engine light always is lit, but it doesn't throw any error messages on the readout.

 

What codes are stored? That's where you need to start.

 

Dah...shoot I have no idea. I just have to think it's something stupid they did while changing the oil. They admitted they unplugged something that goes to the air filter while changing the oil and they thought it would be fixed after they plugged it back in. I wonder if they could have punctured a vacuum line or something like that would cause this symptom. I guess if no one has a guess I'll just wait for my guy to look it over, just had some time and it's driving me nuts what could have happened to it for the 12 hours Goodyear had it between when I dropped it off running fine and picked it up with this problem. I could call Goodyear and ask them for the codes but I doubt they will give them to me after I got angry with them and questioned their competence and told them I'm not coming back.

 

There's no use guessing if the check engine light is on. The codes are there for a reason. If they unplugged the MAF but cleared the codes after it was plugged back in, this may be a coincidental problem.

 

Thank you, yeah makes sense! I'll let everyone know what my regular guy thinks it is when he gets back to me in the next days.

 

Actually now that I think about it the guy at Goodyear said the CE codes pointed to the timing belt or timing belt sensor and it was a bizarre coincidence that it happened during the small window they had the car. I'm out of trust for them, so I decided I would take it elsewhere for a second opinion at that point. Does my problem sound like something that the timing belt or sensor would cause? I would owe Goodyear an apology if, in fact, the timing belt problem started during the 12 hours they had it and they had nothing to do with it! That seems like to bizarre of a coincidence to me though, especially since they told me it was the air filter plug and didn't even test it further after plugging it back in!

 

If its a code for the VVT, it could be low oil or the wrong viscosity. That would explain it happening after the oil change

 

I checked the oil and there was enough. It looked a little dirty though, not too bad but not like new oil, and I mentioned it to the guy but he said the residue from the old oil mixes in with the new and dirties it. Thanks for all your input!

 

But yeah as I am searching around the web, it does look like maybe just using the wrong viscosity can cause real issues like I'm seeing. I called my guy and left him a message referencing this. I guess there would be no way to check what viscosity they used other to to empty all the oil out and fill it with the correct oil. Right? I wonder if I should just have him do that before starting all of this other stuff if the code is showing a problem with the timing belt or the vvt.

 

I'd wait to get the codes before you do anything. Could also be a coincidental problem with the camshaft reset valve or CVVT hub

 

Thanks again. I really love this car and it only has 130k on it. It's black with beautiful tan leather and all the options, I love the heated seats and the front and back fog lights. It snows a lot here in the winter and it's great for cruising right through it all. I am hoping to get it to 300k!!

 

Do the codes tell a mechanic precisely what is wrong or just point you in the right direction? For example, does the code say you have a problem with your VVT due to the wrong viscosity of oil or does it just say there is a timing issue?

 

Keep in mind all of this is pure speculation, since I don't have the codes.

But the codes do not pinpoint the problem. If the shop is using a generic OBD-II code reader, the code description will likely be something about the camshaft position sensor.

Just because a code is for a sensor does NOT mean that sensor is the problem. It means the reading from that sensor is out of range. The tech has to find out WHY it is out of range.

You don't know how many times I've had customers try to fix their own car with a sensor for an oxygen sensor code. They come in with new oxygen sensors and a check engine light and say "I replaced both sensors but the light keeps coming on!" Well, a vacuum leak in the intake system will throw off the oxygen sensors. So they spent $300 on a couple sensors when all they needed was a $4 vacuum elbow or a $75 air pipe.

There is a reason shops charge a diagnosis fee..

So for the cam code, they have to figure out what caused the sensor to read out of spec. If it has CVVT, and they understand how CVVT works, they would know to check the oil first. Of course, theres no way to check the viscocity though.

There are times when an educated guess has to be made, or a series of things may need to be tried. CVVT codes usually start with an oil change, then camshaft reset valve, then CVVT hub. That is because the hub is the most expensive and there is really no way to test and prove an intermittent fault in either the reset valve or the hub.

 

You don't work in Northern Ohio by any chance do you? lol I'd love to find a mechanic like you.

 

Haha nope, sorry