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**mongocanfly** · 11-03-2016, 01:07 AM

You may have a problem with your ecm program..some ecms are only setup to run one fan...mine was that way and it wouldn't work either..I had to get it reprogrammed to run 2 fans and now its fine..I used a psi harness and fan 1 and fan 2 wires go to a set of psi relays..each relay goes to a fan..how did you have yours setup? those water pump housings are very thin...I ran my steam port that way..the original pump was thicker..I had to replace my leaking pump and the new one was only about half as thick as the factory one was.

11-03-2016, 01:07 AM	#7
mongocanfly Post Whore Join Date: May 2015 Location: Alabama Posts: 14,692	Re: 5.3 Thermostat Housing with Temp Ports You may have a problem with your ecm program..some ecms are only setup to run one fan...mine was that way and it wouldn't work either..I had to get it reprogrammed to run 2 fans and now its fine..I used a psi harness and fan 1 and fan 2 wires go to a set of psi relays..each relay goes to a fan..how did you have yours setup? those water pump housings are very thin...I ran my steam port that way..the original pump was thicker..I had to replace my leaking pump and the new one was only about half as thick as the factory one was.