"module" on end of air intake???

[tsukinosaru]

I want to change the carb/intake/air cleaner on my 86 w150
right now its a 318 auto 4wd. If I follow the "snorkel" that comes off of the air cleaner housing it goes to the inner fender on the drivers side, behind the battery. There is some sort of "module" attatched to it with a vacuum diaphragm and a wiring harness. What is this , and more importantly, do I need it if I change intake and carb, or will "bad" things happen?

[acton mike]

I believe this is the dreaded ESA control unit

I do not have one on my truck (too old) but I read of many folks cursing it

[Dodgevanman]

That's exactly what it is. If it's working..leave it alone, but when (not if, but when) it starts to give you trouble, there's a way to get rid of it.

Not one of Chrysler's best ideas.

[tsukinosaru]

what does it do? and how do I get rid of it WHEN it goes bad?

[Dodgevanman]

It's Electronic Spark Advance. It was Chrysler feeble attempt at an onboard computer.

You probably have an electronic feedback carb. as well and an O2 sensor. The ESA controls these items as well.

What you do is get Mopar Performance's electronic ignition kit and you can ditch the ESA. This requires some wiring know-how however. You'll need to do this if you going to be adding a 4bbl. carb. and such.