Hey everyone. I drive a 1994 Volvo 850 that I just purchased last summer. Since I've had this car, I've had an issue with it stalling while driving. I've read some posts on this forum that suggest it could be something with the fuel pump/relay, which the previous owner had also warned me about (although he made the issue sound like it only happened once in a great while, and never on the highway, which was false.)

Anyway, I took it to a volvo specialist who told me that it was the catalytic converter that was giving me these problems and that it would cost about $1200 just for the part. I've been looking around at parts places online that have prices that range from 400-700 dollars for the catalytic converter.

I wanted a second opinion so I asked another mechanic who said that if it is the catalytic converter that needs to be replaced, because it's a '94, he can just take it out and replace it with a pipe. I've never heard of this and I was wondering if anyone could help me out in making a sound decision on what i should do...I'd like to get a couple more years out of this car, as I just got it last summer. Any help is appreciated!

 

Are you in California?
Do you have any check engine light?

If you replace the catalytic converter with a straight, your check engine light would come on informing you the catalytic converter is not working.

If you're not in California, you can get a aftermarket catalytic converter put onto your car for less than $300.

 

Rhode Island.

I get a "SERVICE" light when I start the car, but it goes away after about 2 minutes.

I just don't understand where the $1200 quote comes from for such a small part. Also, does it make sense that the catalytic converter would be the root of this problem? I know I actually DO need the part, but would that cause the car to stall like that?

 

try this first ...all respects to RSPI

 

Thanks for the replies. Any dangers in putting an aftermarket catalytic converter on my 850? I've been looking online at parts and it looks like VOLVO cc's go for around 1000 so I can see why I was quoted 1200, but 300 bucks looks alot better.

 

Magnaflow makes a replacement cats for our cars for under $200, even California approved.

MagnaFlow Catalytic Converters - 49-STATE & CANADA Catalytic Converters For Trucks, Suv's, American Muscle, Diesel, & Sport Compact Vehicles

 

So I finally was able to put an aftermarket cat on the car on Thursday. Ran good as new for the next couple of days and then today while driving, BAM. Died on me at a red light just like before. Any idea where to go from here? This is super frustrating. I replaced the fuel pump relay last summer, and got a new air filter and spark plugs the other day along with the new cat. Volvo experts, HELP please. I love this car and is hate to have to look for a new one.

 

I am sorry I did not see your thread before.

You did not give much detail about your situation. We have to presume that your car starts right back up (otherwise it would be way too easy to fix already). So let's just assume your problem of course is that you're losing fuel or ignition. That could be caused by an intermittent wiring problem, but that sort of thing is hard to find.

So, my car does the same thing. I haven't fixed it yet. Here's what it does. Once a week or so, it'll just quit on the road and then start right back up in about a second (it's a manual). Also, I have had maybe 5 occasions total where it was hard to start. Once it shut off at a stop light and wouldn't restart. I rolled it off the road and then it started. Don't know why.

In a case like this, if a car won't start, the first thing I would do is check the fuel pressure, because I like to diagnose stuff. The 850's have the fuel pressure check port aimed at the throttle linkage, and I really detest that, but you can manage to get a good reading with a tire pressure gauge. I feel stupid admitting I do that, but it does work. Plus they're much cheaper than my real fuel gauge was.

The second thing I would do is check for spark on one spark plug.

If your car starts right back up, then it's really hard to do any testing. My car is like that too, usually, until Tuesday.

So Tuesday morning, it wouldn't start when it was time to go to work. I tried it 3 or 4 times later in the day. I swapped to a spare, equally old fuel pump relay, no change. Put in a jumper wire in place of the relay to test fuel pressure. Had about 42 psig. Started right up after that. PUt the relay back, and just as I guessed it would, it started right up after that and I have been driving it. Diagnostic opportunity is lost. So I also don't know what exactly is the issue.

 

P.S. If your car is a 94 Turbo, then that means you've got an OBDII port, and you can monitor stuff. If you were logging data when it quits again, you might be able to figure it out that way.

 

Did you ck fuel pressure before you put in the FPR jumper?

I would have ckd for pwr (12v) back at the fuel pump; if you have pwr there then you know it's not the fuel pump relay but downstream of that; i.e. the pump itself.

Suggestion to both FBParts and OP: when it happens again ck for fuel pressure at the rail; assuming no or little pressure (spec is about 42-43 psi at idle for up through MY '95) then ck for 12v pwr at fuel pump access cover. If the pump has pwr then you have a bad pump. The pumps generally start to fail after about 130k miles or so (mine's due) depending on how much abuse it's had in its life.

If you do not have pwr at the fuel pump access cover (VOM across fuel pump hot wire and ground wire) then ck the relay by jumpering it; if you now have pwr, then your relay was bad. This is a common failure mode on these cars.

OP: I also apologize I didn't see this thread back in March; could have told you a bad CC would not make the engine stall. At least boxpin pointed you to better solution than stock replacement. Also, if those first two techs told you that's what was causing the stalling, never listen to them again please.

 

It's kind of hard to explain in better detail, but when the car dies, it will sometimes start back up, but other times I have to leave it off for a couple of minutes and try again. Alot of the time when it starts back up, it will immediately sputter out and shut off again. It's unpredictable every time. Also, if i shut the car off to say, get gas or run to the store, I have to give the car a couple of minutes before I try to restart it, otherwise, it'll just stutter and shut off. Thanks for the replies, I'll see what kind of info I can get and report back.

I don't know much about cars, and I brought it to a pretty reputable Volvo mechanic in town, so when he told me it was the catalytic converter I just took his word for it. The cat definitely needed to be replaced but he didnt really diagnose the right problem. I'm glad I saved the money and went with an aftermarket cat.

 

The sputtering and dying is certainly similar to boxpin's fuel pump relay movie:

I am wondering, however, if the fuel pump relay was replaced, maybe the fuel pump might be the problem. I am going to do an experiment; I am going to replace the relay with a jumper wire and see what happens. My car is acting up more and more. However, I don't really think that is my problem. I got a check engine light just this morning when it quit, so I will trip the diagnostics and see what I can learn from that.

 

Okay, well maybe I'll be holding up on that jumper wire. When I triggered the OBDI diagnostic codes, I got codes for crank sensor signal missing and intermittent. This is consistent with something I saw earlier. When the engine quit going down the interstate, the tach went to zero. The engine was still turning about 2500 rpm in 5th gear, of course. Now, I doubt that it's the sensor itself, but I swapped it out with a junk sensor just to see if that made any difference. I also pulled out the computers and looked for corrosion on the connections there, did not see any. They seem to be very robust, so I don't suspect that is the problem. I admit I don't have a spare, though.

 

It turns out it actually wasnt the fuel pump relay that had been replaced, but a fresh air filter (not quite sure how i got the two mixed up...). Anyways, I replaced the fuel pump relay on Saturday, and now on Wednesday I've had no issues so far. The relay that was in the car had a green top to it, and all the videos I had seen for an 850, the relay was an orange color. Im not sure if the relay was bad or just didnt go with the car itself, but the new relay seems to have done the trick. Thanks everyone for your help!