1998 Volvo S70 Need help diagnosing issue. Vacuum leak?

MrMarauder · Post by **MrMarauder** » 12 Jul 2014, 19:56

I have a 1998 Volvo S70 T5 with 147,000 miles. I was accelerating hard today to get out in front of traffic and all the sudden I heard a noise and the car lost power and cut off. Now the brake pedal stays depressed, and it sounds like it has a loud exhaust leak near the front. It will cut off unless I keep the rpm's above 1000. Did something rupture or disconnect causing a vacuum leak? It's not generating any check engine light/code.

Thoughts?

Thanks in advance.

Post by **shaker_chi** » 12 Jul 2014, 21:00

Mr. Marauder,

it sounds like you have more than a vacuum leak. At the front of your engine check the idle air control valve. It has small hose that has almost an "S" shape to it. If the clamps on that give way the hose will come off when you accelerate. If that's not it, go through and check all the turbo hoses. It sounds like you aren't getting enough air. If it was a small vacuum leak the problem would be similar but on a smaller scale and probably more loping when you idle. Good Luck.

MrMarauder · Post by **MrMarauder** » 12 Jul 2014, 21:50

An initial check of the hoses didn't reveal anything loose, but I'll give in another once over. Any turbo hose in particular that would most likely be the culprit?

Post by **abscate** » 13 Jul 2014, 03:36

Top one on the intercooler blew off on my 99... Horrible running after that

Post by **shaker_chi** » 13 Jul 2014, 13:18

Like abscate said, check the one attached to the intercooler. It's difficult to see the connection so get a flashlight and look under the shroud by the radiator.

MrMarauder · Post by **MrMarauder** » 14 Jul 2014, 12:55

Thanks for all the advice. I spent about an hour trying to locate a loose or ruptured hose and could not find one, so I'm going to drop it off at the shop and have them look at it. Hopefully it's nothing too expensive.

Post by **Ben850** » 14 Jul 2014, 15:06

While checking them, squeeze them as well to look for cracks.

I've seen them in the junkyard likely because of the cracked tubes I had discovered.

One was the bottom of the intercooler which you can squeeze to feel for cracks. Another was an idle air hose that you could not see the crack either unless you felt for it.

lastly, I blew off the hose at the throttle body when I first installed the new one. I likely didn't tighten it enough.

MrMarauder · Post by **MrMarauder** » 16 Jul 2014, 19:51

I was not able to determine the fault so I took it to a local mechanic and sadly they also were not able to identify what the issue is, so it's off to the closest Volvo specialist. I believe it's an issue with the turbo and/or connections, but I can't be certain and I'd rather someone with more knowledge of the Volvo setup take a look at it. That said, thanks for the input guys!