Hi everybody,

This is my first post here. I would appreciate some opinions on the issue I am currently having.

I have a '98 S70, non turbo, with 114,000 miles. I've been having an intermittent issue with stalling - or near stalling - while slowing down to stop. It also would surge sometimes, though infrequently, while on the highway. Not having time to mess with it, I took it to a local independent Volvo mechanic who has a good reputation. He initially thought the O2 sensor was bad, but he eventually found a vacuum leak and replaced a vacuum hose and nipple under the intake manifold. But, he was honest about the fact that it likely was not causing the stalling problem. He checked everything, and speculated that it may be a mass air flow sensor or a fuel pump. But he couldn't be sure because of the intermittent nature of the issue. And, to his credit I think, he didn't want to just change parts and charge me.

Based on his ideas, I bought a new MAF sensor (complete assembly) from US Auto Parts on eBay for $77.83. I started with the MAF because it was cheaper and easier to replace. I thought I would move on the the fuel pump if this didn't fix it.

After changing the MAF sensor the car initially ran good. But, the issue was always intermittent anyway. One day does not a fix prove. Sure enough, the next day it started behaving the same way, and the check engine light came on. It had been out for the couple of weeks since we got it back from the mechanic, even though it had continued to misbehave during that time. I bought an OBD II reader for the first time and I pulled the fault codes. It came up with 3 of them:

1) P0103-Mass or Volume Air Flow A Circuit High
2) P0171- System Too Lean Bank 1
3) P0172 - System Too Rich Bank 1.

I'm reading this like the new MAF assembly is defective. After searching this forum, I've found one thread where somebody else had an issue with "generic" MAF sensors. Any other ideas? How about the initial stalling problem? I would appreciate anybody else's opinion.

 

stalling or hesitation or bogging under engine load? or is this at stop lights as well?

sounds like you got a junk MAF, may have been damaged during shipping.

codes 2 and 3 are caused no doubt because of code 1

 

I just wanted to close the loop on this thread. I did have a defective MAF sensor. I was able to get an exchange part. Replacing it solved the issue of the Mass Air Flow code. Kudos to Car Parts Wholesale on eBay. Obviously, its not a good thing to get a defective part. But, I've had defective name brand parts in the past too. When I called they didn't even question the issue. They sent me a replacement immediately. No shipping charges for sending the replacement to me or sending the defective part back.