Should I be concerned? EGR Valve + Timing

[Route66]

looking at picking up a 94 exploer xlt...excellent condition insideout...277k miles on it however...mechanic checked it over and this is his report:
The check engine light is an EGR valve sensor. The repair is going to cost 310. He did look it over and it has a small antifreeze leak around the timing case, said not an issue other than keeping an eye on fluids, just seeping

everything else looks good to me...should I be concerned with the antifreeze leak? will the egr valve sensor cause any problems driving?

thanks!

 

[Masterd]

Having the EGR malfunctioning could cause the engine to run lean...

 

[MrWizard]

will the egr valve sensor cause any problems driving?

To answer your question with a question, how certain are you that the mechanic thoroughly diagnosed the problem?

IF the problem is the sensor, then no, it won't cause a problem driving. The sensor simply detects whether the
EGR valve opened when the PCM tells the vacuum regulator to apply vacuum to the valve.

IF the problem is the EGR valve itself, or a clog in the exhaust tube, then you'll get the same code.
Although you might notice a rough idle, some pinging, and/or running hotter than normal.
The actual code simply says "the sensor tells me the EGR valve didn't open". You have to do some troubleshooting
to determine if it is the vacuum regulator, the valve, carbon clogging the tube from the exhaust, or the sensor.

IF you're certain it is the sensor, this is trivial to replace yourself. $70 and a couple of turns of the ratchet.
It's a silver box about the size of a deck of cards, on the driver's side of the intake manifold.
With two vacuum hoses and a electrical connector on it.

 

[Clarke]

ive got a 93 and think my egr is acting up where is it located?