Did some hack drill out my intercooler weep hole? Topic is solved

Post by **slickdizzy** » 22 Sep 2020, 12:55

As I’ve worked down the list of issues with my recent 1998 V70 LPT acquisition I’m now fighting an intermittent P0171 CEL. I completed a full stage 0 with all new boost and vacuum hoses along with many other new parts, and the car seemingly runs and drives great. I even smoke tested it using a DIY smoke tester and could not find any obvious leaks; chasing down the CEL has proved troublesome as the fuel trims just slowly go negative until they hit -25 with no rhyme or reason.

Well today it came to mind that I should check the intercooler weep hole area to make sure there are no cracks or damage in that area and I was shocked to see a hole roughly 1/2” in diameter where the factory weep hole is! I have no idea how I overlooked this before.

I have seen a fair amount of evidence on this car already that it was worked on by someone with a low skill level in the past, now I’m wondering if they drilled this out in an attempt to solve some kind of problem. Volvos have never had an intercooler weep hole THIS BIG, right?

Luckily it seems I can repair this easily enough by drilling an appropriately-sized weep hole in a common 1/2” hole plug and epoxy it into place, but I wanted to make sure I’m not missing something first...

Post by **jimmy57** » 22 Sep 2020, 12:58

Nope, that was a 2mm hole when the intercooler was made.

Post by **slickdizzy** » 22 Sep 2020, 13:44

I suppose I shouldn’t be surprised given this is what I found when I went to replace the rear cam seal...

Post by **scot850** » 22 Sep 2020, 13:55

Up here in Canada the local dealer foreman recommended opening this hole up a little as we have an issue with the intercoolers freezing in the winter with condensation as it does not drain fast enough. When this happens you have to either put a heater under the car to thaw it out or if it starts let it idle for a while. If you don't the car will just not move.

As the engines wear and especially the turbos and PCV systems clog, more oil can end up in the intercooler and clogs the passageways (like your arteries) so any additional condensation is easily trapped and freezes.

However 1/2" is extreme!

Neil.

Post by **slickdizzy** » 22 Sep 2020, 14:13

As it tends to be, probably a classic case of noble intentions with questionable execution...

Post by **Sveedy** » 22 Sep 2020, 15:47

scot850 wrote: ↑22 Sep 2020, 13:55 Up here in Canada the local dealer foreman recommended opening this hole up a little as we have an issue with the intercoolers freezing in the winter with condensation as it does not drain fast enough.

Kind of puzzling considering where these cars come from.

Post by **slickdizzy** » 22 Sep 2020, 17:14

Well, Home Depot came through with a fix. Off-idle stumble is now gone and long-term fuel trims are hovering around -6% after an hour of driving. Feel like kind of an idiot for not noticing this sooner.

Post by **FLXC90** » 22 Sep 2020, 18:46

slickdizzy wrote: ↑22 Sep 2020, 14:13 As it tends to be, probably a classic case of noble intentions with questionable execution...

I've never seen staked cam seals. I think I have seen this guys work on airplanes though!

Post by **jimmy57** » 22 Sep 2020, 19:01

Stake cam seals is the fix when you don't know the seals pop out because your crankcase vent box is plugged.

Post by **slickdizzy** » 22 Sep 2020, 20:11

jimmy57 wrote: ↑22 Sep 2020, 19:01 Stake cam seals is the fix when you don't know the seals pop out because your crankcase vent box is plugged.

Indeed, that was my assumption. This car was clearly the victim of a non-Volvo mechanic who troubleshot symptoms, not causes. Nonetheless, I was a little disappointed to see they didn't even drive the replacement seal in straight.