92sihbk

Completely rebuilt my Z6 in my hatch.. got over 1500 miles on it now and its smoking black, i havent lost any oil, no CEL's, no nothing. What sensors can cause my engine to run rich? I have shitty gas milage too.

Engine has new cap, rotor, fuel filter, plugs, O2. everything.

Bad TPS, MAP sensor are my guesses.. What do you guys think? Are there any other sensors that can cause this?

Just looking for some ideas, thanks guys

97Ej6mike

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 92sihbk &raquo;</TD></TR><TR><TD CLASS="quote">Completely rebuilt my Z6 in my hatch.. got over 1500 miles on it now and its smoking black, i havent lost any oil, no CEL's, no nothing. What sensors can cause my engine to run rich? I have shitty gas milage too.

Engine has new cap, rotor, fuel filter, plugs, O2. everything.

Bad TPS, MAP sensor are my guesses.. What do you guys think? Are there any other sensors that can cause this?

Just looking for some ideas, thanks guys</TD></TR></TABLE>

Bingo, black smoke is soot/richness, not oil. Your motor is pouring too much fuel in, due to a bad or clogged MAP and/or O2 sensor. If the MAP is not functioning correctly, it will not get correct readings of whats going on in the manifold (Manifold-absolute-pressure) , same goes for the 02, if it is worn/old, it may not throw a CEL right away, but it will give false readings to your ECU, thinking its not running right, therefore putting more fuel in than necessary

As for TPS, as long as your gas pedal has a feel to it ( you can rev it correctly through all RPM's, it doesnt hesitate) than it shouldnt be on your list of concerns at all.

Luserkid

If its fully built with new pistons and stock ecu/basemap then thats your problem. Built motors are suppose to be broken in on the dyno not in your neighborhood. 1500 miles is more then enough to expletive up the rings.

92sihbk

no, the head is built, but i bought it with the car like that. I just had it gone through, regrind all the seats, new intake valves and guides and seals. The bottom end is rebuilt with new bearings, and the pistons are just re-rung with new OEM honda rings. block was also bored .20 over.

97Ej6mike , i have the honda service manuel for my car, and i did a test on my map sensor to see if it holds vacuum, and it did so i figurted it was still good..

Oh, and it does have a new O2 sensor.. But yea it is deffenitely black, sooty.


Thanks guys keep em comming

97Ej6mike

Well if the MAP and o2 are good, then the only thing that comes to my mind is that it needs to be tuned on a dyno or at a shop (road tune). Running this rich isnt detrimental to your car in the time being, but your gas mileage will suffer to say the least .

Oh and so will your exhaust tip and bumper, lol. Your going to be cleaning it off allot.

92sihbk

any way the passage to the map sensor on my throttle body could be clogged?

slowcivic2k

It could but then your ECU would throw a MAP sensor Range/Performance code. If you have no codes, then everything is fine according to the ECU.

Get your car tuned.

speedooo

try a p05 ecu and see if still runs rich...that ecu is for the cx d15b8 8v with a 5800 rev limiter, if you still pour out black smoke theres an issue

gsrhatch2356

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Luserkid &raquo;</TD></TR><TR><TD CLASS="quote">If its fully built with new pistons and stock ecu/basemap then thats your problem. Built motors are suppose to be broken in on the dyno not in your neighborhood. 1500 miles is more then enough to expletive up the rings. </TD></TR></TABLE>

Well this is the first time I have ever heard anything like this.

I bet if you ever had a rebuilt motor it didnt last more than 1500 miles. sorry to let you know but break in period is light driving not geting on it on a dyno.