v70 1998 coolant loss mystery p0303 code Head gasket?

HenryD · Post by **HenryD** » Mon May 13, 2019 5:58 pm

I have a v70 1998 NA with 230k
6 mo ago I had rough idle which would smooth out after a short time running
I also had a slow coolant leak
I fixed the leaks and the rough running went away
I started to have coolant push out of the expansion tank several months ago
This went on for about 2 months until I had only h2o in the system
Now the reservoir is holding level but the rough running has come back
The thought is it is a head gasket but no water in oil no oil in the water no mess in the trannie oil.
I fixed the PCV system several years ago but I have oil on top of the cyl head now.
I put new volvo spark plugs cap and rotor and they seem good except cyl 3 is a light brown not the white the others show
I installed a new t stat and new temp sensor last year Not sure if my coolant fan is working because I never hear it come on.
I just drove the car from boston to phili and back I got 24+ on the way down and around 20 going 72 mph on the way back
the car ran nicely once it gets warm but that is even starting to have more stumbling even when warm.
Did not loose any coolant (still H2O only) the system does not seem to pressurize when hot. Hoses still not stiff
I read that a vacume leak or manifold gasket could cause the coolant reservoir to over flow but I cant find that post again.

Help!

tardcart · Post by **tardcart** » Tue May 14, 2019 4:59 am

do a compression test to see if there is low compression in two adjacent cylinders. If so scrap. if not, put 5 AC DELCO radiator tablets in the expansion tank or better in the hose for the radiator. Its only wheat and will not clog anything but works to seal small cooling head leaks. then put 50/50 back in, water will boil out when hot, and then fix the fan or make sure its working, then chase down stumble if still present. It seems like you have given up though.

Post by **abscate** » Tue May 14, 2019 5:08 am

If you ran only water through winter it’s likely you damaged the block and head. In summer, running only bad water will also damage the block if the engine gets hot.

You need both coolant and water for heat management.

HenryD · Post by **HenryD** » Tue May 14, 2019 6:55 am

I ran water only when it was above freezing. I tightened all the spark plugs changing one of them to number one cylinder from number three the stumbling seems to have abated quite a bit I checked all The injector connections and I will do a compression test in the near future and report back to you guys thank you for your help and concern

HenryD · Post by **HenryD** » Tue May 21, 2019 3:30 pm

I ran water only for the past 3 months while it was boiling out.
the mysterious miss fire was a bad spark plug I found by moving the one from cyl 3 to 5 and then to 1 got miss fire codes and replaced it
all good there.
I have put anti freeze back into the system with some water. I am not sure why people say you have to use distilled water so I did not but I have the majority of coolant as anti freeze probably 70%
The compression test cyl 1,2,4,5 200 on the nose cyl 3 190 pretty good for 230k 1998
still which to know if it could be a leak that does not allow the system to pressurize which is then causing the coolant to push out of the expansion tank
I need some help with testing my radiator fan. It never seems to come on and I never over heat. I replaced the temp sensor a couple of years ago the one under the t stat.
No water in oil no oil in water no water in trani oil
Need some answers please help