bad head gasket or valve cover gasket

[chrisjm91]

I was leaning towards an air leak as well. Right after I did the pvc system I got an EGR code, I replaced the gasket but haven't vacuum tested yet. A few months later I got a po171 I think it was, system to rich. Found a loose vacuum going to the charcoal canister. Replaced it & cleared the codes. Tge system too rich code never reappered but the EGR code did. I cleared every now and for about 2-3 months and it hasnt come back on in over a week. But now I have this terrible occasional miss after start or after a complete stop and the oil on the plug, along with my mentioned new codes. Ive replaced all the vacuum lines, EGR gasket & intake manifold gasket. I will try to find the leak though tomorrow, and change the plugs.

As far as live data stats. At idle today after start up from sitting for ten hrs was 16.8 and rose to 21 over a 20-30 min drive. The engine temp topped out at 210. I will post a pic of my stats in just a sec... thanks again for all your help.

[chrisjm91]

Here you go. Hope this helps. The number style stat info was at idle. I broke the graph into 2 different stages per say. The beginning us idle, where it drastically declines about halfway through is where I gave it gas and revved to 2500rpm and held it. The long-term trim seems to stay 13% at idle then after a little bit of driving it goes to about 20%, give or take. The car as you can started about 190 degrees then went to 206 degrees. I see what you're saying about running lean and I agree but no code for that yet.

[draser]

MAF reading zero at idle?

[chrisjm91]

Yes I just double checked The MAF Readings. It reads lbs/min. At idle its reading 0.0, if I rev to 2k I get 0.1?? at 170 degrees fuel system1 is reading open loop then goes to closed loop fault at about 180 degrees. And still at idle the LTFT is at 13.2 & STFT alternating -0.8 to +4.6. But like I said; when I get to driving LTFT goes to 20+

[chrisjm91]

Ok so I just took a quick drive with my scan tool. The only thing ive done since the beginning of this thread was clean my spark plugs. Again at idle LTFT was at 13.2 & STFT was alternating And I was at about 180-190 degrees, all at idle. During the drive LTFT dropped to 10.2, UNTIL the return drive it rose to 19.0 and I was at about 206 degrees.... please help im so confused. Ive had nothing but trouble with this car but I love the car.

[draser]

Can you unplug MAF and inspect connector to make sure it's clean? Also look at wiring condition. Any work done in tbat area recently, any squished wiring that you can see? I think you've found your problem.

[chrisjm91]

I inspected the wiring and connector. I left the engine running and pulled that maf sensor. Once I did that the stft called for a lot less fuel but ltft never changed. I replaced the spark plugs and took a new reading. The stft stayed at zero for a good min then started jumping up and down again. I sprayed carb cleaner around the engine but got no response. I cannot find any maf stats for the volvo 850 turbo. I checked fuel pressure by pressing on the relief valve on the rail and it squirted out strong.

[jenkinskg]

So my car has thrown a random misfire code and P1310 code. It has been misfiring occasionally after start up, long starts, and misfiring on stop-and-goes and long term fuel trim is at 25%. I just started delving into everything to find the culprit and this what I found: the base of the plug wires were dry but had evidence of oil. Didn't think much of tjat because I had to replace the PVC system due to it being clogged and so it put oil on the top if the engine from the breather next to the plug wires. So I figured that was from it. But then I pulled the plug and here I am.

I am not sure if this is due to the head gasket or valve cover gasket? I am losing a little bit of oil but not losing any coolant. Can anybody point me in the right direction, head gasket or valve cover gasket to get to the tube gaskets? Also if it helps; I had this engine put in under 2 years ago and im thinking they replaced the valve cover gasket but I dont know about the spark plug tube gaskets. Any advice would GREATLY appreciated, thank you!

Very easy for careless people to spill oil into spark plug hole when adding oil, then it shorts out coil, happened to my moms s60 years ago

[abscate]

Thanks for reviving this thread.

If you look upstream you will see the classic drop in STFT when you rev up that confirms a vacuum leak as cause of problems