Intercooler no longer working efficiently??

[RMeadows]

I noticed recently that the air venting out of my BOV is warm/hot as opposed to cool/cold like it has been in the past. The cold side piping is also hot to the touch aside from the very first pipe coming directly off the intercooler. Does it maybe just need to be cleaned or what? I've only had it on the car for a few thousand miles.

 

[kenamond]

I noticed recently that the air venting out of my BOV is warm/hot as opposed to cool/cold like it has been in the past. The cold side piping is also hot to the touch aside from the very first pipe coming directly off the intercooler. Does it maybe just need to be cleaned or what? I've only had it on the car for a few thousand miles.

First, I have some questions:
o Is your profile up to date?
o How do you know the temperature of the BOV recirc'ed air?
o You say "venting". Are you recirculating your BOV or venting to the atmosphere?

The intercooler doesn't cool the air down to "cold". It makes it colder than when it entered, but it will still be hotter than the outside air. Sure, if the intercooler is dirty, it will be less efficient at cooling the incoming charge, but a perfectly clean SMIC is still going to discharge hot air - but cooler than the inlet air.

Also, if you're driving the car hard, stop, and touch the intercooler, it may burn you. If you are taking it easy and feel it, it will be warm.

I can't say if your IC is dirty, but it's pretty easy to remove it, straighten the fins, clean it out, and reinstall it. Anything that gets you under the hood is a good idea.

 

[RMeadows]

First, I have some questions:
o Is your profile up to date?
o How do you know the temperature of the BOV recirc'ed air?
o You say "venting". Are you recirculating your BOV or venting to the atmosphere?

The intercooler doesn't cool the air down to "cold". It makes it colder than when it entered, but it will still be hotter than the outside air. Sure, if the intercooler is dirty, it will be less efficient at cooling the incoming charge, but a perfectly clean SMIC is still going to discharge hot air - but cooler than the inlet air.

Also, if you're driving the car hard, stop, and touch the intercooler, it may burn you. If you are taking it easy and feel it, it will be warm.

I can't say if your IC is dirty, but it's pretty easy to remove it, straighten the fins, clean it out, and reinstall it. Anything that gets you under the hood is a good idea.

Sorry. Haven't bothered to put my mods in there yet. I have a front mount and am venting to atmosphere(MAFT Blow-Thru setup).

I just know that the air used to be cold when it vented out of the BOV and that the cold side piping also used to be somewhat cool to the touch. With other turbo cars I have had it was the same. The air coming out of the BOV was noticeably cool, this is not the case with my car right now. I realize the air is obviously being cooled to some degree considering how hot it is when it runs thru the hotside of the intercooler, but it still seems too hot with what i've experienced in the past. The only thing that doesn't make me question it's effectiveness is the fact that if I was running 20 pounds of boost without an intercooler the car would knock like crazy, and right now(haven't tuned it yet) i'm only getting about 6 counts of knock so it's obviously doing it's job.

If you have anyone you know that is venting to atmosphere have them rev the car up to like 7K and let off and stick your hand in front of the BOV, the air should be quite cool. Maybe it's just the hot weather, i'm going to give it a try at night and see if it feels any cooler to me.

 

[kenamond]

If you rev the motor up to redline without any load, your turbo is probably only getting a couple psi boost max, so the compressor is not really heating the air very much. It might just be that that big FMIC is holding heat longer than a smaller IC, so after a hard pull, the FMIC gets toasty (not heat soaked, but hot), but its thermal mass is high enough that it continues to release that heat into the airflow running through it after the pull.

If you just warm the motor up but don't do any hard driving, does the BOV dump warm air?

Are you still running the stock VC breather setup? If so, you might have some oil in the IC. How hard is it to pull the pipe off the intake endtank and check for oil film?

Or maybe it's the weather.

 

[RMeadows]

If you rev the motor up to redline without any load, your turbo is probably only getting a couple psi boost max, so the compressor is not really heating the air very much. It might just be that that big FMIC is holding heat longer than a smaller IC, so after a hard pull, the FMIC gets toasty (not heat soaked, but hot), but its thermal mass is high enough that it continues to release that heat into the airflow running through it after the pull.

If you just warm the motor up but don't do any hard driving, does the BOV dump warm air?

Are you still running the stock VC breather setup? If so, you might have some oil in the IC. How hard is it to pull the pipe off the intake endtank and check for oil film?

Or maybe it's the weather.

See that's the thing. This was just after I had started it up in the driveway and let it reach normal operating temperatures. I would expect it to be nice and cool, but it was not. The cold side of the core is nice and chilly as is that very first pipe coming off it, but after that the piping gets hot. I thought maybe it was because it wasn't getting any air to it to help with the cooling so I took it for a nice spin and tried again and it was the same. warm blasts of air. The car was just put back together(blew my old turbo) and I had the core off and it was fine inside and out aside from a bunch of bent fins.

next cool night we have down here i'll test it out again and see how she does. thanks for the replies

 

[kenamond]

See that's the thing. This was just after I had started it up in the driveway and let it reach normal operating temperatures. I would expect it to be nice and cool, but it was not. The cold side of the core is nice and chilly as is that very first pipe coming off it, but after that the piping gets hot. I thought maybe it was because it wasn't getting any air to it to help with the cooling so I took it for a nice spin and tried again and it was the same. warm blasts of air. The car was just put back together(blew my old turbo) and I had the core off and it was fine inside and out aside from a bunch of bent fins.

next cool night we have down here i'll test it out again and see how she does. thanks for the replies

Here's a thought: if the pipe that's cool is welded to the endtank, and it's made of aluminum, it's going to conduct heat into the intercooler and be cooled. If the next pipe is connected with a silicone coupler, it won't conduct heat back to the intercooler. Unless you are using v-band t-bolt clamps or something which force the pipe flanges together at the coupling, I suspect that the pipes aren't conducting into each other.

I guess it doesn't make any difference unless you're having problems. Dunno.

 

[Dream On]

If you're revving the car at a stop (so no air is flowing through your intercooler) and feeling the air coming out when the BOV opens then it probably shouldn't be cool. Think about it, the IC really isn't doing anything when you're not moving, except maybe dissipating a little heat because it is larger.