abs causing engine surge on 1994 Acura Integra

i drive a 94 gsr, the abs light had been coming on and going off for awhile, no it stays on, when i pump my brakes it causes my engine which is already reving high to surge, pump a few times and it shoots up to 2500rpm then down to around 800, then settles around 1600rpm where it idles, the car has many upgrades but always idled around 900, any suggestions?
Thank You

Asked by for the 1994 Acura Integra
Not really an answer, just some suggestions...
Did you check for any vacuum leaks, or that it holds vacuum after the engine is shut off? Have you tried removing the fuse for the ABS pump and pumping the brake pedal to see if it does the same thing? Any ABS faults when you look for codes?