Hello to all, been a long time since my last post/question.
I am always reading/ lurking in this excellent site.

A little history before my question.
Check engine came on a few months ago with a running lean/rich code.
Cleared it never came back. Time goes by and start getting more codes.
Misfire multiple cylinders 1,2,4. Cleared the codes no problems for a day or two. Misfire again number 2 cylinder only. So I change the plugs b/c it's over due (check all for spark/gas/ compression- yes to all) clear the codes car runs good. Then more misfires in cylinder 2, blinking check engine plus a water temp sensor code, maf code. I do the temp sensor and thermostat (which was broken open) clean the maf, clear codes car runs ok. Now the radiator is leaking profusely at the bottom of the passenger side. Starts out like a slow drip then empty's the reservoir in 15 miles. So I park it and the car Never over heats. Finally it will not start. Cranks and cranks, turns over but won't start. The car sits for two weeks. Now I never say die so I replace the radiator and the upper and lower hoses. Fill the system with coolant and try to get it started.

I can hear the fuel pump turn on when the key is in the number 2 position. The plugs have spark and I can smell gas on the plugs. I try and pull out the fuel pump relay and put it back in for fun. Cranked the car over and over it sounds like it wants to start, pumped the pedal, an then it starts. But man does it run rough, like it's misfiring. Sure enough code comes up over and over cylinder number 1 misfires.

I let the car warm up and go for a drive to purge the air from the coolant system. It idles between 900-700 dropping and fluctuating at stop in gear. Neutral balances it out but not much. Step on the gas a little and the engine shakes like its misfiring. You can drive it but it just runs so rough, same code number 1 misfires, what is going on?

Car has 264,000 on it.
Cap, rotor and wires, o2 sensor were all done 2 years ago.
Plugs are new, MAF was replaced at around 100,000 which is old I know!
If you unplug the MAF the car does not run any better or worse.

Now there is a ton of obfuscation here and I'm sorry for the ridiculously long post. Just wanted everyone to have the background before offering advice.

Thanks to all who contribute.
Greg-

 

Hi Greg, bad MAF. Also, have you looked in the cap lately? I would also do a quick compression test to make sure a valve has not burned.

 

Compression is 120, 90, 120, 120, 115 in the five cylinders.
It's been that way for years. I'm sure the number two has a sticky valve.

Yeah I looked in the cap today and the contacts were a little warn out.
Tried to clean off the carbon but it had no effect on the cars running.

MAF is what I think too since unplugging has no effect. In fact if the car is running with the MAF unplugged and then I plug it in, the car dies.

Just want to be 100% sure though. Ive put about $350 into this car in the last month and don't want to keep buying parts.
New MAF and cap w/rotor is going to be another $200.

 

Probably more than that but hey, less than car payments.

 

So cap, rotor, and MAF replaced today.
No change, runs rough and after a short drive the #1 cylinder miss fires.

Got a few new codes I've never seen P00BE, P1FF8?
They are kind of unusual obd2 codes that are Volvo specific?

So any ideas?

 

Recheck compression in #1.

What brand parts did you use?

 

Different video.

 

Bosch for everything of course. Yeah I love Roberts videos and have seen that one before.
I'll recheck compression and timing. But I get the feeling the head gasket is finally toast.
Debating wether to do that job or let it go.

 

We love our S70 GLT. I'd keep it.

 

Any idea about those strange Vadis codes?
I tried to check the net and here but with no joy.
One was a code about insufficient air?

 

No I don't. Seen them once about a month ago.

 

Made an attempt at further diagnosis last night.
Sprayed the ignition coil and wires with a water mist and looked for arch.
The sides of the coil clearly have a leak of energy.

So we're on to throw more parts at it to see if that fixes the problem.
The only thing I can't figure out is why only one cylinder is miss fireing?
It is the furthest from the coil in terms of distance but
why there are not multiple miss fires puzzles me.

 

Just wanted to report back to close this thread.

One of the new spark plugs was bad and the coil was bad.
I replaced both and she is purring again.

What a nightmare glad it over.
Hopefully this helps someone else down the road.