99 S70 randomly stalling

mtm3200 · Post by **mtm3200** » 21 Jul 2009, 08:56

Hi, I have a 99 S70 with 230k miles and recently its been randomly stalling or almost stalling. It usually happens when I'm driving slower (25-30mph) or when stopped at a light/waiting in traffic. All of a sudden the rpm's will drop and bounce up and down a little like it's "running out of gas" (the tank has always been well above half full when this happens) and the orange arrow starts flashing. Sometimes it completely stalls or instantly bounces back up to normal operation and the arrow stops flashing. The last time it completely stalled, I was waiting at a light and it refused to start back up. About 3 seconds in to the fifth try of holding the key in start it fired right up without any hesitation and I drove home without any problems. I'm about to order a fuel pump relay but thought I would post here and see if anyone had any other thoughts.

Thanks,
Matt

Post by **MadeInJapan** » 21 Jul 2009, 10:55

Usually a flashing light indicates a transmission issue- if yours hasn't been flushed, I would recommend it. Also, I would check the MAF sensor as your symptoms sound vaguely familiar and like it is either dirty and needs cleaning or replaced. Being a '99, your car might also be suffering from the ETM issue- Read through the posts in that area of this forum to see if anything comes to light. Also, last of all- get your trouble codes read to see if your computer might shed some light.

mtm3200 · Post by **mtm3200** » 21 Jul 2009, 17:46

Thanks for the info, MIJ!

okay, so I went to Advance Auto Parts today to get the codes read and it came up blank. No codes. Maybe it only sets a code for the check engine light?

I will get some cleaner tomorrow and see about cleaning the MAF. I have also been meaning to get the transmission flushed but the price the dealer wanted for the fluid seemed really high...is it normally expensive?

My ETM is a "white sticker" version and the car has over 230k miles which has me wondering how it lasted this long...but I'm not getting a check engine light or an ETM light so hopefully that's not the problem.

Matt

Post by **Ozark Lee** » 21 Jul 2009, 23:27

Be very careful when cleaning the MAF. Just spray it with the MAF cleaner and let it dry. Don't try to scrub it and don't even touch it - they are very sensitive and they can be permanently damaged if touched.

You can flush your own transmission, it just takes a bunch of milk jugs, a plastic hose, a bunch of ATF, and some patience. A new clip for the quick connector at the radiator doesn't hurt either and it is a dirt cheap part.

Details are here:

https://www.matthewsvolvosite.com/forums ... php?t=8767

...Lee

jallert · Post by **jallert** » 04 Aug 2009, 10:57

how do you clean the MAF? is it located right after the air filter? do I spray the whole things down with MAF cleaner? or just the sensor (looks like computer chip) in the middle? any tips or diagrams? Thanks.

Post by **Ozark Lee** » 04 Aug 2009, 11:37

Just spray the element - the part that protrudes into the MAF assembly tube.

...Lee

jallert · Post by **jallert** » 04 Aug 2009, 12:30

the little sq piece that looks like a computer chip? Could this help a rough idle and/or O2 sensor fault code that keeps going off even though the O2 sensor is new? thx

Post by **Ozark Lee** » 04 Aug 2009, 14:48

the little sq piece that looks like a computer chip?

That's it. It can help with the rough idle and it may or may not help the O2 sensor code - it depends on which code it is.

...Lee

jallert · Post by **jallert** » 05 Aug 2009, 13:14

PO133 is the fault code. Don't know if it is front or rear O2 sensor. But it is going "out" abt every 6 months. Can I clean it? MAF or Brake cleaner? I read abt a "torch" methods that burns off the contaminants from the sensor and you clean it with MAF cleaner. Thoughts? Thanks.

Post by **Ozark Lee** » 05 Aug 2009, 14:36

P0133 is a front O2 sensor faulty signal - signal too low. It sounds like a connection problem. You can use MAF cleaner on the connection - it is just a glorified electrical contact cleaner.

What kind of replacement O2 sensor did you put in? I have heard of many problems with the splice box on the Bosch universal. If you have the splice box type you might want to try getting some heat shrink tubing and solder the splices together.

...Lee