Anyone familiar with Volvos?

[Bdubs]

My brother has a 1991 Volvo 740 non turbo with about 220k on the ticker that he got from his boss for $200. Not a bad deal, the car starts right up and idles fine, but it blew a heater hose a few weeks ago, and ever since it has never run right. Now, its been nothing but a battle to get the car to run correctly. Perhaps this is a totally unrelated issue.

I just can't solve the issues with the car stalling for no reason at all. It'll idle fine, even in Park, if you rev her up, she'll go to 3k rpm's with ease, and fall right back down to idle. BUT, Put it in Drive, try to go up the driveway and bam, it dies, throws two CEL's as well. And then, it'll start right back up!

I'm thinking something is wrong with the fuel pump or something with the delivery system, however those aren't the CEL's I'm getting. One for a MAF, and another for a temp. sensor in the intake as well. But, they only are triggered when the car stalls.
And the fuel pump is getting adequate load when I tested the wire.

I'm at a loss, and about to roll this beast into the pond. Anyone have any opinions other than junk it? haha.

I've replaced the fuel pump relay, put a new TB on it, cleaned all the intake parts out, got a different MAF, and nothing has changed.

I've joined 3 volvo forums and not one person has replied in over a week, some help they are.

[Swift Subaru]

My brother has a 1991 Volvo 740 non turbo with about 220k on the ticker that he got from his boss for $200. Not a bad deal, the car starts right up and idles fine, but it blew a heater hose a few weeks ago, and ever since it has never run right. Now, its been nothing but a battle to get the car to run correctly. Perhaps this is a totally unrelated issue.

I just can't solve the issues with the car stalling for no reason at all. It'll idle fine, even in Park, if you rev her up, she'll go to 3k rpm's with ease, and fall right back down to idle. BUT, Put it in Drive, try to go up the driveway and bam, it dies, throws two CEL's as well. And then, it'll start right back up!

I'm thinking something is wrong with the fuel pump or something with the delivery system, however those aren't the CEL's I'm getting. One for a MAF, and another for a temp. sensor in the intake as well. But, they only are triggered when the car stalls.
And the fuel pump is getting adequate load when I tested the wire.

I'm at a loss, and about to roll this beast into the pond. Anyone have any opinions other than junk it? haha.

I've replaced the fuel pump relay, put a new TB on it, cleaned all the intake parts out, got a different MAF, and nothing has changed.

I've joined 3 volvo forums and not one person has replied in over a week, some help they are.


Disconnect the Maf. See if it still stalls.


*Edit, just saw new maf. Hmmm Do you know thats a good Maf?

[Bdubs]

I did that, and it doesn't die, car stays consistent rpms.
So, my other MAF isn't any good either I'm assuming.

[fantomas]

i had a similar problem w/ my svx.. it would start up fine... and randomly stall while driving and idling. i think it ended up being the cam or crank sensor (i can't remember now)

[Dusty B]

i had a similar problem w/ my svx.. it would start up fine... and randomly stall while driving and idling. i think it ended up being the cam or crank sensor (i can't remember now)

More than likely a cam sensor. Usual rule of thumb is a vehicle can operate without a cam signal (usually throws cel), but cannot function without a crank signal. If it's a constant crank signal problem the car will not start.

I'll tell you right now, I HATE working on volvos. My old roomate had a 95 sedan whatever numeric designation with the in-line 5 cylinder non-turbo.......
oh the headaches that car gave me!

Because it's only happening in drive (with movement I'm assuming.), I'd check the vss input sensor for the pcm....

[ScrapinSTi]

could also be a vacuum leak... Something that is only triggered under a load..

[Bdubs]

I've been troubleshooting this for a while now. I'm amazed how many people have problems with these cars just randomly stalling and stuttering, and for many different reasons.

I went to Boyd's and the guy let me snag a MAF off another Volvo, but damn, it most be a popular part. There had to have been about 15 740/790's there and I grabbed the last MAF, which is probably no good.
I was also thinking one of the sensors, but I figured the car wouldn't operate properly even if it were in Park.

It is way too damn cold to mess with it today, I'm just trying to gather up some more ideas.

[Bdubs]

Fixed it.
There were a few things wrong which eventually led to the demise of the whole intake system screwing the whole air/fuel mixture all up.
I meant MAP sensor, car has no MAF, btw. Just an air temp. sensor and MAP. The MAP was shot, so I got a $30 one from Advance from a 90 Chevy Celebrity (same part, believe it or not, but less than half the volvo price). Also the Vac tube going to the manifold from the MAP was caked with crud, air temp. sensor wasn't plugged in correctly, and the IAC valve was dirty as hell as well. I also took out the TB and reset the idle screw and cleaned that out.

After cleaning everything, it ran just fine. I also took out the fuel pump, because the sender was making the gauge stick. Took it out, resoldered some wires, and that works now too.

Thank god! :nw: It only cost me $50 to get it running, but I probably spent over 10 hours troubleshooting, and back tracking.

[Judau]

I've joined 3 volvo forums and not one person has replied in over a week, some help they are.

For future reference, even though it's mostly for turbo Volvos, a few of my friends are on http://www.turbobricks.com

If you havn't already, you might want to try that out as well?