Hi folks,

My XC70 AWD 2006 cannot start, but let me give you some background.

One month ago I noticed that the car was bogging down when I was accelerating on the highway, let's say, it was hesitating before getting up to the speed I wanted.
I thought it was time to replace the spark plugs which were 100K old, so last Saturday, I replaced the original Volvo sparks with the NGK 7092.
The old sparks were really worn, besides #3 #4 and #5 were soaked with oil... #2 and #5 were just worn.
I think the reason why #3 #4 and #5 were soaked with oil is because 6 months ago I realized the PCV hose was broken, I replaced it but there was plenty of oil next to the ignition coils location. I cleaned everything but I guess the oil might have gone down the threads of the sparks.

http://www.mediafire.com/view/k3r2he3bb1j4sb7/IMG_20190122_211740.jpg

Anyhow, once the sparks have been replaced, the car started immediately and the engine sounded totally different, very smooth and clean.
Yesterday, after a few minutes I was driving the car (cold start, I am in Canada so well below freezing point right now) the engine almost stopped, as if not enough fuel was getting there, I pulled over, did not touch the throttle pedal, after a few seconds the engine rpm went up to normal again.
This morning, no start at all.

I was convinced something was wrong with the ignition coils, but the VIDA errors say something different.

http://www.mediafire.com/view/r42irtc5rzgjn0j/2019-01-22_ECM-640D.png

http://www.mediafire.com/view/5keh82blajbtc9c/2019-01-22_ECM-640D_Details.png

http://www.mediafire.com/view/v29b6gn19gf9ppe/2019-01-22_ECM-640D_Details_V2.png

http://www.mediafire.com/view/jriy7x9hd7y0qmf/2019-01-22_ECM-929D_Details.png

I was able to start the car again one more time while I was plugged in with VIDA, the engine stayed idle for about 10 minutes, then it stopped.

I understand the meaning of the codes, but I do not know where to start from.

Any chance this is related to the spark plugs or the ignition coils or anything I might involuntarily done during the replacement?
It is difficult for me to think of a pure coincidence.

Many thanks for your advice :)

Alex

Oil cannot 'seep' down the spark plug threads and coat the electrodes, impossible. They were probably soaked in unburned gasoline.

Pull your expensive spark plugs and check the tips for the proper gap - .028 inches or the metric equivalent. The Volvo engines do not like platinum plugs, the copper core are much better and cheaper and are designed to last 80K Km.

Your car is 12 years old, it is time to start looking for vacuum hose leaks.
--
Keeping it running is better than buying new

I also have another XC70, 2005, same sparks, never a problem.

I can verify the gap again.
How if I find them soaked again?

Also, can the VIDA errors I got be, someway related to a bigger electrode gap in the spark plugs?

Platinum spark plugs, do they need to have the same gap as the copper ones??

Alessandro

You need a feeler gauge to check the gap. It is supposed to be .7mm regardless of plug type. If 2,3,4 are coated again, you might have problems with the coils or your compression is too low. Swap the coil from #1 to #2 and #5 to #4 and see if the problem moves to the 1 and 5 cylinders. If so, you might want to look around for new coils.

I suspect the errors you got are related to the unburned fuel that makes it to the converter and O2 sensors.
--
Keeping it running is better than buying new

Hi there,

The reason of the errors was the low compression, due to my negligence, the intercooler pipe was completely disconnected on the back of the engine.

See picture: http://www.mediafire.com/view/0pk7dgelf2i1gbd/IMG_20190126_100508.jpg

Most likely the reason is because when I tightened the clamp, I did not fully push down the hose in the connector, so it popped out.

Once I realized the issue, I was (and still I am) pissed off with myself, I am always very careful on everything I work on, in addition, I removed/re-hooked that hose multiple times in the past, never an problem... I cannot explain this stupid error.

I removed the spark plugs, made them 0.030", no oil on any on them.

Did a VIDA check, clean.

Well, I hope at least I made you laugh!

Thank you for your time anyhow.

Alex

Don't feel bad, I and a few others have done the same thing. When I blew it, I was 'testing' out my PCV work. While giving it full boost, the IC hose popped off and I barely made it home. It took me an hour or so to diagnose and 2 minutes to fix it. Now, I religiously grab the IC hoses and try to twist each one after reconnecting, if it moves at all, the clamp is loose or the connection is bad.

Live and learn.
--
Keeping it running is better than buying new