Running rich and won't idle properly

[Turtle]

Hey guys, my 93 400E runs rich and idles around 100-200 rpms. I've replaced basically the whole ignition system other than the ecm. I have a new cat that I'm going to have installed next week but I don't think that's the problem, and I don't want to blow out new cat from it running rich. When I floor the car going straight it blows out a good amount of black smoke from the exhaust. Another issue I'm having, when I start my car in the morning it blows out a little puff of white smoke from the exhaust. It doesn't really blow any when I'm driving normally, but if I do a donut or slide the car sideways, it blows out an extreme amount of white smoke then it will clear up after driving for about 5 miles. I don't notice any oil or coolant leak so I don't know which gaskets I should start replacing. If anybody has any thoughts on this, any advice will be much appreciated. Thanks!

 

[gsxr]

What spark plugs brand/model do you have in there? Pull them out for inspection, are all 8 black/fouled, or do all 8 look normal, or do some look different than others?

I'm assuming this is a new/different problem than your last issue: http://www.500eboard.com/forums/showthread.php?t=9362

:?:

 

[Turtle]

What spark plugs brand/model do you have in there? Pull them out for inspection, are all 8 black/fouled, or do all 8 look normal, or do some look different than others?

I'm assuming this is a new/different problem than your last issue: http://www.500eboard.com/forums/showthread.php?t=9362

:?:

They are plugs that I got from Gerry, and I have a brand new set. I'll pull them today when I get back in town and let you know what they look like.

Well, my last problem was trying to get it running on all 8 cylinders, which now it is.

 

[gsxr]

Also check the LH module part number, for grins. If it's firing on all cylinders and still running that rich, something is fishy. Also make sure the FPR is good... better yet check fuel pressure with/without the vacuum hose attached to the FPR.

 

[Turtle]

Also check the LH module part number, for grins. If it's firing on all cylinders and still running that rich, something is fishy. Also make sure the FPR is good... better yet check fuel pressure with/without the vacuum hose attached to the FPR.

What should the pressure read out too? Plans changed and I won't be able to work on my car until the end of the week, so I'm making a list of everything to check haha.

 

[gsxr]

What should the pressure read out too? Plans changed and I won't be able to work on my car until the end of the week, so I'm making a list of everything to check haha.

Very roughly, fuel pressure with engine running should be 46-48psi with the vacuum hose connected, and 56-58psi with the hose removed. When the engine is turned off, wait 30 minutes and the pressure should be above 35psi (if not, the fuel pump check valves may be leaking down).

See attached for official specs from FSM.

 

[Turtle]

Very roughly, fuel pressure with engine running should be 46-48psi with the vacuum hose connected, and 56-58psi with the hose removed. When the engine is turned off, wait 30 minutes and the pressure should be above 35psi (if not, the fuel pump check valves may be leaking down).

See attached for official specs from FSM.

Okay so I checked my fuel pressure, everything is to specs of what you told me. After it sits for 30 minutes it is at 50 ish psi. I changed out my spark plugs and all of them were pure black, looked like diesel soot on them lol. I feel like a complete idiot because the mass air flow sensor was unplugged and I don't know how I never noticed it lol. So with that plugged back in, and the new spark plugs, she idle pretty good and doesn't run near as rich that still leaves, where the coolant or oil is leaking from. Is there any common gaskets that go out on these cars? I feel like it might be an intake manifold gasket because it only smokes when the car is leaning a lot and at high rpms. It's almost like its spilling into the cylinders. Thanks for the help so far man! Good to know my fuels system is fine