We love our Volvo. We bought it used in 2000 with just over 20,000 miles onit. It now has close to 130,000 miles on it and has been a great car. One thing that has been happening on and off from years (yes, years - but getting worse) is this:

You will be driving down the highway and it feels like it is"kicking" ever-so-slightly - like maybe it wants to quit if given half a chance (ie: stopping at a stoplight). You can usually get it to kee pgoing if you do get stopped at a stoplight by putting it in N or P and revving the engine (continuously). Once you stop and turn off the car (say, stop at7-11 before getting to work) and start it back up, it's fine, but the initial go can sometimes cause some questionable moments as to if the car is going to stay running or not.

We've always taken the car in for 10,000 interval maintenance. Our mechanichas looked into the problem before, but never seems to find anything.

Any thoughts and ideas are appreciated. If not for this one"little" thing, our car would be perfect!

 

Maybe you have a bad spark plug, spark plug wire, rotery or distributor cap.
Coil possible also. Check them or replace them if they haven't been changed.
Fuel filter been changed? Any codes?

 

Our Volvo guy has never said anything about codes specific to this (we just had the car in a month ago and had a new radiator put in, it's 120,000 service, and new rotors and brake pads). We'd had new spark plugs and wires put in a year or so ago. I'm not sure about the other items; I'd have to check our maintenance records.

 

If its running that badly, the computer should pick it up. Are you getting a check engine light? If so, take it to a parts house for a free code reading.

I had a Lincoln that used to do that sometimes and it turned out to be a bad coil pack.

 

We don't have any lights on indicating there is a problem. I will check into this coil pack you speak of. Thank you!

 

I experienced a similar problem with my Volvo that was due to deteriorated vacuum hoses, specifically the two small hoses that attach to the turbo waste gate and bypass valves. Mine were absolutely cooked and leaking after 75K miles with the vehicle having had only dealer care until I recently got it.

These attach on the back side of the engine and are not noticeable unless you are looking for them. If you look straight down in the vicinity of the upper motor mount, you will see them.

I would also check the three larger vacuum hoses that attach to the drivers side of the intake manifold. The get cooked almost as badly the turbo hoses do.

This problem doesn't fully match your symptoms, but I would check it out to eliminate that as one of the possible causes. This never caused my Check Engine Light to go on either.

Let us know what you find.


-Paul

 

Thank you! I will check this out and report back. Appreciate the reply.

 

My husband and I hooked the car up to a OBD reader yesterday and no codes came up. We inspected the hoses and they all look good (there are a lot of new ones under the hood). I know our mechanic recently replaced quite a few on them when he put in the new radiator. So, we are still stuck...

I did notice when I was sitting in the car while taking the readings that the way it was running, even in the garage, reminded me of when I had my '65 Mustang and it would be running "rough". When it did that my Gramps would always say to take it out on the highway and "blow the carbon out of it" and it always seemed to do the trick. I know a '65 Mustang is a lot different than a '98 Volvo S70, but that is what it reminded me of. You can tell it just isn't "firing on all cylinders" or whatever that saying is.

 

HAs the MAF been cleaned or replaced?

 

I had a chance to look at all of our maintenance records last night. I saw this problem was first reported in 2005. Soon after they checked and replaced the spark plugs and spark plug wires and checked the distributor cap. Hoses have been kept up and a couple of mentions of new vacuum lines. There was no mention of an MAF replacement, so I'm going to start there. I will take it to our mechanic and report back. It's such a great car! If we can get this sorted out we will be able to keep it forever! Thank you so much for all the replies! It's been fun learning as I go!

 

It could be several things, my suggestion is not to start replacing a part before making sure it really is faulty.

Given there are no codes, a Volvo dealer could make you replacing several things to no avail. I would be aware.

To me, that seems like the car doesn't get enough fuel or the fuel pressure is not adequate. This could be due to a list of things, such as a clogged fuel filter or a faulty fuel system sensor. May be even the fuel pump, but usually it gives up quite quickly when worn. The fuel pump is known to give up when the car runs out of fuel (a scenario to avoid).

As mentioned, try also cleaning on both sides the small wire inside the MAF sensor with a wet q-tip, with care. But I don't think it could really be the culprit.

The coolant level is steady?

 

We are going to replace the MAF ourselves and go from there. I did look through our maintenance records again and it doesn't look like the fuel pump has ver been replaced, but we'll start with the MAF replacement because we can do that ourselves. If that doesn't work we will continue onward with the help of our Volvo guy. More to reports to come. Thank you for all the posts of help - very much appreciated!

 

Bad or torn vacuum hoses can cause these issues. Most of them CAN NOT be found while still installed on the car. You have to remove and inspect them.

 

Happened to be at Walmart last week and saw they had Sea Foam (I had read a lot about it on this and other sites) and added to the fuel tank. Since then we haven't had any issues. I also ordered the MAF last week too. Now I'm wondering if I should keep it or return it due to the fact that it seems to be running fine again after a bottle of Sea Foam. Not sure how long it's going to last, but $8 vs. $150 sounds like a better ROI.

 

1 can for 3 consecutive tanks of gas for best results