Help with beef short ribs

[Bigredcat]

My son and I tried smoking a rack of beef short ribs and ran into some issues that I`m hoping someone can help with.  Dan brought a vacuum-marinated 5lb rack of short ribs to smoke this weekend. We placed it in my stock DBS, pre-heated to 260 on the second rack from the top, then reset the temp to 220. When it hit 175 IT (after about 5 hours) we wrapped it in foil and put it back in the smoker. To our surprise the IT actually began to drop, even though the tower temp was still reading about 210. After giving it a couple of hours and finding the temp still not increasing, we opened the foil and closed the smoker again. By 7:00 (9 hours of smoking) the temp had dropped to about 160 IT so we gave up. The ribs were delicious (I mean REAL good) but the connective tissue had not broken down completely. We had hoped to get the IT to 190. I have a couple of theories, but any input would be most helpful.
1) we should have left the ribs open instead of wrapping it until the IT reached the desired 190
2) it is possible that when we opened the foil, it interfered with the sensor and the tower temp wasn`t the 210 that it displayed.

Additional details:
- we used a second digital probe to double check the IT - both read the same
- vent was wide open through the whole cook time
- hickory smoke was applied for 4 hours
- when we opened the foil, there was quite a bit of juice-marinade in the bottom, which we left

[beefmann]

it  sounds  like the connective tissue was  breaking  down and creating juices in the  foil, next time let the ribs go another  hour in the smoker before  putting into  foil, or cook  longer in the foil a box temp of  220 is a good temp... just  need to dial in the  process to your  liking and method...I also  like to  smoke like what you  have  done then wrap in foil..  just takes  practice and experimenting

[Habanero Smoker]

Foiling tends to shorten the cooking time, and brings the IT up quicker. The collection of liquid in the foil is common, even if the ribs were not marinated.

When you took the IT and noticed the drop, where you measuring it at the same spot or area?

I have seen an IT drop as much as 5°F, but I can't think of any reason why the IT would have such a drop, other than you may have been getting a wrong cabinet temperature reading, and you were cooking at a much lower temperature than what was displayed. Do you have a probe thermometer you can use to monitor the cabinet temperature? Many of us use the Maverick ET-732.

The foil could have interfered with the sensor, if by opening the foil you completely covered the racks, thus trapping the heat.

[rveal23]

Bigredcat, I have dealt with that issue as well. I don't know what happens, I think it might be our Probe.  I pull the butt, then foil it up and it starts to drop even though the cabinet is still hot.  After a while I get frustrated and stick in another probe and that starts to read more accurately. I think its time we look into the Maverick ET-732. 

[Bigredcat]

After reading the posts in this forum I have to agree with rveal. I think it is time to power up a bit with a second element and a more accurate temp control.