Can I rollover 401k to IRA with loan against it?

The value of your 401k minus loan balance can be rolled over into an IRA if your plan permits doing partial rollovers. Some plans don't and require you to rollover the entire balance. That is if your 401k is with the past employer. If it is with the current employer the chances are - you can not (unless they will allow you to do an 'in-services distribution' which is unlikely). So if you get OK to rollover the balance and continue paying the loan - you are OK. Otherwise the outstanding loan balance will be considered a distribution which will result in taxes (and penalties if you are under retirement age). 
You need to contact your plan administrator or custodian and discus this. 

The retirement rules allow for it as long as the employer sponsoring the 401k is on board with it. In other words, the employer may require the 401k participant loan paid in full before the 401k balance can be transferred to an IRA.

Nowadays, however, most former employers will allow you to transfer the outstanding 401k loan to another 401k including a self-employed solo 401k plan.

Lastly, a 401k participant loan cannot be transferred to an IRA as the rules do not allow for it. MySolo401k.Net

You can rollover the net 401(k) balance but cannot roll over the loan. IRAs are not permitted to have loans.

If you terminate employment where you have the 401(k) loan, many plans will require you to pay the loan in full within 60 days. Any unpaid amount would then be considered a default and treated as taxable income to you in that year. And if you’re under age 59.5, the default amount would also be subject to the federal 10% penalty tax for premature distributions.

I hope that helps.

SecondHalfPlanning.com