1995 E300D.....No TACH and LOW IDLE after glow plug replacement....

[BigRed0803]

Just going to give it a shot in this forum also to see if anyone had any advice. I recently replaced the glow plugs in my 95 E300D when I put everything back together I started the car and it took an extra second to start than normal. All the glow plugs are brand new the glow plug light is now working like it is supposed to, but time and time again when I start the car it doesn't start right with the flick of the switch like it always has, it takes an extra second and when it does start the engine idles much lower than it normally did. Another thing I noticed is now my TACH doesn't work at all. I have a friend that has the exact same car, he let me switch his OVP relay which did nothing, I also swapped the ELR relay and checked all the fuses which made no difference. All I can think of is that it may be my engine wiring harness because the two plugs you have to unhook to remove the intake were in bad shape total bare wires exposed on both these connectors. I guess removing these connections could have affected the wiring harness? Any other suggestions of what my problem could be, could the CPS be the problem and it just choose to happen when I R & R the glow plugs? Thanks for any help