Funny thing today, as I took my truck into the dealer for the cps install. I talked to the mechanic about keeping my old one that still worked and how was the new one going to improve the truck over the old one. After a long talk and some conning, he gave me the one he took out of the truck and replaced it with one that was bad that he had around. When he did he told me that from now on , about ever year or two , take out the cps and wipe the back of it off and reinstall it. The reason he said is that there will be a build up of residue left on the back of the unit that will cause a missing and ruff idea if let go. He did show me a real bad gummed up one that said he removed earlier in the day that cause the truck not to run at all. Has anyone else heard of this as this is a first for me on our web site. But it could make sence if you think about it causing a bad reading on the sensors. Lets hear anyone on this one.