Black smoke when starting
Thread Starter
Intermediate
Joined: Oct 2013
Posts: 43
Likes: 0
Black smoke when starting
Notice I get black smoke when I start 1993. It's not burning oil. It also smells to be burning really ritch. Just changed the spark plug and wires. It was doing that before new plugs and wires.
Egr or opti?
Any guesses?
Egr or opti?
Any guesses?
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
Got ANY codes showing?
if NOT,
then I would guess that your injectors are leaking down when shut-down and the fuel is collecting in the intake and burned the 1st second of the engine running. IF it continues to burn RICH after that initial fire up, then you may have more serious injector OR regulator problems.
As with ANY other engine problem, start with fuel pressure test, leak down time table, Ohms test of the injectors and reading the codes.
if NOT,
then I would guess that your injectors are leaking down when shut-down and the fuel is collecting in the intake and burned the 1st second of the engine running. IF it continues to burn RICH after that initial fire up, then you may have more serious injector OR regulator problems.
As with ANY other engine problem, start with fuel pressure test, leak down time table, Ohms test of the injectors and reading the codes.
Melting Slicks
Joined: Dec 2003
Posts: 2,334
Likes: 11
From: las vegas nv.
Got ANY codes showing?
if NOT,
then I would guess that your injectors are leaking down when shut-down and the fuel is collecting in the intake and burned the 1st second of the engine running. IF it continues to burn RICH after that initial fire up, then you may have more serious injector OR regulator problems.
As with ANY other engine problem, start with fuel pressure test, leak down time table, Ohms test of the injectors and reading the codes.
if NOT,
then I would guess that your injectors are leaking down when shut-down and the fuel is collecting in the intake and burned the 1st second of the engine running. IF it continues to burn RICH after that initial fire up, then you may have more serious injector OR regulator problems.
As with ANY other engine problem, start with fuel pressure test, leak down time table, Ohms test of the injectors and reading the codes.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
More likely you just need new valve stem seals.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
Got ANY codes showing?
if NOT,
then I would guess that your injectors are leaking down when shut-down and the fuel is collecting in the intake and burned the 1st second of the engine running. IF it continues to burn RICH after that initial fire up, then you may have more serious injector OR regulator problems.
As with ANY other engine problem, start with fuel pressure test, leak down time table, Ohms test of the injectors and reading the codes.
if NOT,
then I would guess that your injectors are leaking down when shut-down and the fuel is collecting in the intake and burned the 1st second of the engine running. IF it continues to burn RICH after that initial fire up, then you may have more serious injector OR regulator problems.
As with ANY other engine problem, start with fuel pressure test, leak down time table, Ohms test of the injectors and reading the codes.
The codes will better direct you to the issue.Black smoke = rich fuel
Blueish-white smoke= burning oil
DUB
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
You may notice that the O2 sensors may not be working correctly due to being flooded with gas for so long...depending on how long this problem when on until you found it. All of them may need to be replaced if you still feel like you smell rich fuel. Also a rich fuel condition will result in a long time for the system to go into "closed loop" due to the excessive fuel is keeping the O2's "cold" and not allowing it to go into closed loop becsue they can not heat up as designed.
DUB
Last edited by DUB; Nov 12, 2013 at 07:38 PM. Reason: more info
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Melting Slicks
Joined: Nov 2013
Posts: 2,264
Likes: 3
From: Orchard Park NY
Is car stock?
Black smoke is def. running rich. My modded c4 puffs a good amount of black smoke on startup, and who knows how much when ******* it. NOT GOOD... In my case, I need to get that tuned out with custom tuning. If you are stock, probably that o2 sensor you mentioned was causing that issue.
Black smoke is def. running rich. My modded c4 puffs a good amount of black smoke on startup, and who knows how much when ******* it. NOT GOOD... In my case, I need to get that tuned out with custom tuning. If you are stock, probably that o2 sensor you mentioned was causing that issue.
Melting Slicks
Joined: Nov 2013
Posts: 2,264
Likes: 3
From: Orchard Park NY
I think stock ecu would calibrate for such small adjustments in air quantity (somebody correct me if I'm wrong). So I'm betting its a bunk o2 sensor. You will probably need the codes cleared out manually.
Melting Slicks
Joined: Nov 2013
Posts: 2,264
Likes: 3
From: Orchard Park NY
Honestly I'm not sure on these generation OBD1 cars. I"m typically a European guy, where I'd hook up vcds and blow away the code (otherwise in Euro cars you'll never get rid of the code). With these I'm not sure if a battery pulls or not... hopefully somebody more knowledgeable will chime in. I'm just re-learning my way around American v8's the past several mos 
