Ive put a intake, header, and exaust on my 98 civic ex and now it's running rich. What should I do to solve the problem?

 

How do you know its running rich?

 

but have you tried disconnecting the battery for a few and let it relearn fuel mixture?

 

Standing behind the car, its almost like putting your nose over a gas tank. Plus, their is black smut on the bottom of my bumper. Every time I wash my car, it comes back within a day or two.Also when you punch the gas, there is a little bit of black smoke that comes out of the exaust. Ive checked my spark plugges, and at the end of each plug(where the thread runs out) its black. The bar that over laps the electrode is a greyish white color.

 

I have white stuff on my plugs but not as rich as yours. Someone told me to check the timing. My compression was low until I poured oil in each cylinder. The compression improved. Unburnt gas was washing down on the cylinder walls causing poor compression caused by poor timing. The unburnt gas mixes with the oil and probably causes the oil to burn.

I'm about to pickup a timing light to check mine next week and put new plugs in and see what the difference is. My wires may need replacing too.

Your situation seems more extreme than mine since I don't get black soot on the bumper. What's your compression like?

 

I have a friend that did the same to a prelude. The computers in hondas are very basic and do not cross check them selves like Audi or such. the fuel enrichment (pulse width) is learned for one setup , when you change it, it is still for the original setup, when changing cfm and backpressure you push fuel through the engine at a higher rate. causing unburnt fuel (black stuff). if resetting the comp dont solve it, change map sensor manifold vaccuum to the closest fitting line to the head and add a delay valve inline. if those two fail back your timing (retard) a degree at a time and try it step by step. everyone says advance for power. but, when you mod you must retard, as it is much much more efficent with higher rpms at a load .

 

what ever plug you are using give your local parts store the number and increase the last digit by one it is a hotter plug. which you will need.

 

I had this problem in my 98 Civic DX after doing a mini-me swap and adding intake, header, exhaust, and such. I convertd to OBD-1 (a little pricey) and got my ECU tuned using Crome. Runs great!