-40C loss of boost

[andrew70T]

1st post..always wanted to join! I noticed this is a really old thread, but I figure another suggestion may help anyone that comes across it in the future...

I'm no expert, but... in a nutshell, I have a V70 2.5T 06 Stage 1 Rica Tune- 180,000km. Came across low boost problem recently (summertime, Ontario) and ended up replacing tcv, hoses and eventually checking the wastegate actuator/rod assembly on the turbo. The rod had eaten/rusted into the pin, causing a few mm gap, letting boost out when it began building. Tightened the nut, problem gone.

Today, -20 Celcius, after passing on the highway, hit about 10 psi, felt like overboost and about 10 minutes later, in town, the car couldn't get out it's own way ... revs on acceleration were rising with nothing over 1 psi on the boost gauge. Sat in the right lane all the way home...without a grin on my face to say the least.

Got home, pulled on the actuator rod to see if the spring was flexible, but it barely moved. I figure the wastegate wasn't opening or closing properly or the rod mechanism/hinge that controls the wastegate was frozen or had expanded and jammed on opening and/or closing.

Drove it again within the hour and got into 4th (automatic) on the highway and gave it some gas and the boost came back..(unjammed wastegate)? ... will check on it, but I think that may be the problem with cold weather and low boost (sometimes!).

Hope this helps...

[IVIUSTANG]

1st post..always wanted to join! I noticed this is a really old thread, but I figure another suggestion may help anyone that comes across it in the future...

I'm no expert, but... in a nutshell, I have a V70 2.5T 06 Stage 1 Rica Tune- 180,000km. Came across low boost problem recently (summertime, Ontario) and ended up replacing tcv, hoses and eventually checking the wastegate actuator/rod assembly on the turbo. The rod had eaten/rusted into the pin, causing a few mm gap, letting boost out when it began building. Tightened the nut, problem gone.

Today, -20 Celcius, after passing on the highway, hit about 10 psi, felt like overboost and about 10 minutes later, in town, the car couldn't get out it's own way ... revs on acceleration were rising with nothing over 1 psi on the boost gauge. Sat in the right lane all the way home...without a grin on my face to say the least.

Got home, pulled on the actuator rod to see if the spring was flexible, but it barely moved. I figure the wastegate wasn't opening or closing properly or the rod mechanism/hinge that controls the wastegate was frozen or had expanded and jammed on opening and/or closing.

Drove it again within the hour and got into 4th (automatic) on the highway and gave it some gas and the boost came back..(unjammed wastegate)? ... will check on it, but I think that may be the problem with cold weather and low boost (sometimes!).

Hope this helps...

That's interesting, my car has since been totalled, but I have a buddy with a 1998 S70 GLT that doesn't boost in cold weather. I'll check this out on his.

Thanks,
Jesse

[scot850]

I wrote about this before, but this is a fairly common problem here where it gets that cold. The warm air condenses in the intercooler and freezes which causes a blockage, which then makes the tubes collapse. The first time this happened to my 98 XC the car couldn't get enough power to move! I thought the trans had failed.

A few things you can consider:

1) The dealer here in Calgary, used to drill an 1/8th inch hole at the lowest point in the intercooler to allow moisture to drain.
2) When it gets warmer, remove the inter-cooler, and have it thoroughly cleaned to remove old oil residue which traps the condensation (just did this on our V70 XC).
3) Install what we call the 'Saskatchewan radiator blind' (no disrespect meant, it is actually a compliment to the inventiveness of the folks there). This is a piece of cardboard fitted on the inside of the radiator grill to reduce the cold air entering the intercooler and preventing as much moisture build up. I use zip-ties to hold the cardboard in place through the grill. In Sweden, Volvo used to sell a really neat plastic cover that fitted over the grill to prevent this happening. Unfortunately this is no longer available

Hope this helps

Neil.