I have a 1992 camaro with the 305 5.0l tbi engine when i run it it has some black smoke coming out the back and smells like to much fuel,fouled a new set of plugs pretty fast, i just put a new set in last night and it runs great idles perfect no backfires but the black smoke it still there, what could cause this and how do i go about makin it run right i know its gettin way to much fuel i replaced the coolant sensor on the front of the intake cause mine was broke

 

Check your CTS - dead or malfunctioning CTS will cause ECM to command rich mixture. It is located next to thermostat housing and has a two wire connector with yellow and black wire.

//RF

 

already replaced it today and still does the black smoke thing

 

SES light on?

 

CTS (which it sounds like you already replaced) and the O2 sensor would be at the top of my list. Should be replaced on general principle anyway if you don't know how old they are. Also check for good spray pattern from the injectors- no dribbles or streams of gas coming out, just a fine mist.

Beyond that, beg borrow or steal a scan tool and see what the computer is seeing. Just because the sensors are fresh doesn't necessarily mean the ECM is seeing them correctly- a broken or shorted sensor wire won't be obvious just looking at the engine, but can blind the ECM to a critical input source.

I'm assuming this is a stock engine, not modified. If modified, the chip tuning comes into question as well.

 

& wait to throw new parts at this problem until after you get her scanned.
Also, look for corroded grounds and broken connectors....

//RF

 

alright where do i get a scan tool ? prob take it somewhere and have em check it out and my service engine light isnt on
the engine is modified it has a cam and roller rockers and headers thats about it

 

can i use winaldl to check for error codes will i be able to tell why its running rich with winaldl

 

You can check error codes and see ECM operational parameters with WinALDL provided that you check your ECM service number before hand. It should be 1228746 or 161??? WinALDL was designed to read data streams from C3 ECM's at 160 baud. Later ECM's ( and some TPI ECMs) are capable of operating at higher rates. Most likly you have '8746 which you can interface to from a lappy running WinALDL and cable.

GL

//RF

 

so when i run winaldl what numbers and sections should i look at for trying to see why it is running rich thanks alot

 

Before hand make sure that you can I/O between lappy and ECM.

Look for CTS to be real range -80 to 90C with a fully warmed engine.
Make sure that O sensor has enough cross counts (O2 values should OSC about 450 mV, but actual values will be swinging from low 100 mV to high 850 mV.
MAP should read between 1.5 to 2.0 Volts at idle (stock engine about 17 in-Hg vacuum)
TPS should read 600 mV at idle and about 4.5 V at WOT.
If you have IAT it should be reading nearly ambient air temeprature warming up as engine warms up.
For a rich condition look for BLM values to be 110-120 range - ECM is taking out fuel.
Perform a data log - dump it into excel and you'll able to see what ECM is doing from cold start to full warm up.


//RF

 

thanks man i pmed you with couple questions

 

sorry but making a reply is the only way i know how to put this site on my subscription notification.

 

Right above the very first post is a tab on the right side that says "Thread Tools". If you click that, you get an option to "Subscribe to this thread".

 

thanks - i will remember that.

 

hi, had same problem .. found a crack in vacuum line going to map sensor. fixed it .