98 V70xc Starts then immediately dies

New2Volvo98 · Post by **New2Volvo98** » Sat Dec 05, 2020 3:08 pm

Hello all,
I know this topic has been discussed on other threads but I have yet to find an answer to the problem I am having. Hope someone on here can help me out. I bought a 98 v70 xc with 184,000 miles. I especially liked this one because it was a Cannondale edition which I thought was pretty cool. The car ran and drove ok but the started was going out and it sounds like a small exhaust leak somewhere. The previous owner didn't really have any maintenance records so I decided to replace the spark plugs, plug wires, distributor cap, oil cap gasket (leaking oil) and the PVC because I wasn't sure if it had been done before. After I got everything put back together I went to start the car and it ran for about a second and then died. It did this over and over. When it runs for the few seconds it has a really rich gas smell. I have checked the fuel pump relay and jumped it and have pressure coming from the fuel rail so I don't think it's that. I made sure all hoses, plugs and vacuum lines were plugged back in. I took off the antenna ring and sprayed electronic cleaner on the pins, I thought maybe could be a the MAF sensor. I had cleaned it when I first got the car. I unplugged the MAF and started the car and it actually stayed running but ran TERRIBLE. It was puffing out white smoke and smelt terrible of gas. Could a bad MAF cause all this. I have read that typically if your MAF has gone bad you can run the car without it plugged in and it will run better. Any help is appreciated because I am kind of at a loss here. The only thing else I can think of is maybe a cam sensor but I don't want to keep throwing money and parts at it hoping to fix it. Thanks!

Post by **abscate** » Sat Dec 05, 2020 3:14 pm

On any turbo car an induction leak will make for rough running, especially at idle. You can’t visually inspect these , you have to remove each piece, inspect, and reinstall carefully, replacing any bad clamps or rubber. This is 10x more likely than a failed sensor or part swap problem

New2Volvo98 · Post by **New2Volvo98** » Sat Dec 05, 2020 8:07 pm

I thought about that but I assumed I put it all back properly but i will check all the intake hoses and clamps just to make sure. Thanks for your feedback.

Post by **abscate** » Sun Dec 06, 2020 2:58 am

It’s easy to get the spark plug wire order wrong, triple check that. The Haynes manual even gives the wrong firing order in some manual versions.

At some point diagnostic equipment is needed, compression test for motor, fuel pressure gauge for the fuel delivery

hipcheck · Post by **hipcheck** » Mon Dec 07, 2020 6:33 pm

Take a picture of your intake manifold just left of your throttle body. Post it here.

I had the VERY same problem you described

This was the problem:

The PCV retaining clip was between the intake manifold and the engine block. Huge vacuum leak. Here is a screen shot from the FCP video I followed while I did my PCV and the moment in the video where I realized my clip was in the wrong spot!

I hope this is all that is wrong with your car.

Post by **erikv11** » Mon Dec 07, 2020 7:30 pm

+1 to hipcheck's comment. Check that.