Difficult Eidolon (PF)

[Slylizard]

So I'm DMing Pathfinder and am having trouble dealing with a PC's Eidolon.

I'm not worried about combat, I can manage it there, it's the out of combat situations that are troubling me, especially the movement (quadraped) and ludicrously high perception checks.

LAst session the PCs ran through a dungeon, the Eidolon found ALL the traps (poor rogue never had a chance) without even trying, and was able to chase down any and all enemies to the extent that the other PCs had trouble getting involved in the fight.

Now I know it's built correctly, and I know the usual answer is "talk to the player" but I'm curious as to if there are any ways to pick on an Eidolon without being cruel. I basically simply want to balance the encounters right, which involves extra tweaking for the Eidolon.

Any suggestions?

[Waker]

Well first off, is the Summoner actually stating that the eidolon is actively looking for traps at all times? Because that will slow down the speed which the party can move, since actively using Perception requires a move action. Secondly, even if it can find traps, it can't disable magical traps without the Trapfinding class feature, so that might be something to consider.
As for the creatures speed, you might consider adding terrain that hinders it. Difficult terrain, standing water, vegetation... Enemies might also utilize alternate movement methods such as flight, teleportation or swimming which would put the eidolon back onto even ground with the rest of the party.
Alternatively you could have the enemies use tactics which would be effective against a solo foe. When they "retreat" and are pursued by the eidolon, once away from the party they might turn on the eidolon and defeat him before reinforcements arrive. It's simply bad tactics to run ahead of the party.

[avr]

A quadruped may have some difficulty with say, climbing a rope or a ladder. Sure, the summoner can dismiss it and resummon it at the other end, but that takes a minute and loses them the eidolon while it happens.

Eidolons aren't usually that hard to kill, with so-so AC, less HD than the PCs and less protective behaviour from the player controlling it - you said it was sent off chasing down defeated enemies. Actually it might make an excellent red shirt to demonstrate the killer moves of the enemy of the day, especially since it can be summoned back again tomorrow.