Running rich is this normal?
Thread Starter
Member
Joined: Nov 2008
Posts: 402
Likes: 0
From: Hendersonville North Carolina
Car: 1991 Black Z28 G92
Engine: 350 for now
Transmission: wc t5
Axle/Gears: factory 3:42
Running rich is this normal?
I have a 350 with the 22lb injectors. But I have the 305 ecm. Would this be the reason my car is running rich? I can smell the rich exhaust when setting at a light, and if I floor it there is blackish puff of smoke out the tailpipes. But this only happens when it's warmed up to temp. When it's cold it dosent do it and she runs like a champ. And sometimes it's hard to start the car like its flooded and when it fires there will be some smoke.
I was just wondering if this is because I still have the 305 ecm or if there is other problems I need to look into?
oh and I did check the fuel pressure and it's ok. I also ohmed the injectors and they are ok also.......
I was just wondering if this is because I still have the 305 ecm or if there is other problems I need to look into?
oh and I did check the fuel pressure and it's ok. I also ohmed the injectors and they are ok also.......
Moderator
iTrader: (1)
Joined: Mar 2002
Posts: 18,432
Likes: 233
From: Chasing Electrons
Car: check
Engine: check
Transmission: check
Re: Running rich is this normal?
I have a 350 with the 22lb injectors. But I have the 305 ecm. Would this be the reason my car is running rich? I can smell the rich exhaust when setting at a light, and if I floor it there is blackish puff of smoke out the tailpipes. But this only happens when it's warmed up to temp. When it's cold it dosent do it and she runs like a champ. And sometimes it's hard to start the car like its flooded and when it fires there will be some smoke.
I was just wondering if this is because I still have the 305 ecm or if there is other problems I need to look into?
oh and I did check the fuel pressure and it's ok. I also ohmed the injectors and they are ok also.......
I was just wondering if this is because I still have the 305 ecm or if there is other problems I need to look into?
oh and I did check the fuel pressure and it's ok. I also ohmed the injectors and they are ok also.......
Any chance you also did headers and the O2 sensor is further downstream from the engine? If so that will do it. The O2 cools off and the BLMs head for the sky, adding fuel once in closed loop.
Maybe a new engine, or some new sealants for the intake? That can cause the O2 sensor to go south.
As for using a 305 MEMCAL (this is the '91 in your mini-sig?), the ratio of engine displacement to injector flow is the same between the two engines. So the fueling shouldn't be too far off.
RBob.
Thread Starter
Member
Joined: Nov 2008
Posts: 402
Likes: 0
From: Hendersonville North Carolina
Car: 1991 Black Z28 G92
Engine: 350 for now
Transmission: wc t5
Axle/Gears: factory 3:42
Re: Running rich is this normal?
You should get a data log and look at it. See what the BLMs are doing.
Any chance you also did headers and the O2 sensor is further downstream from the engine? If so that will do it. The O2 cools off and the BLMs head for the sky, adding fuel once in closed loop.
No headers. its the stock manifold
Maybe a new engine, or some new sealants for the intake? That can cause the O2 sensor to go south.
it's a used engine from an old chevy suburban, But I did put (used) 083 heads and tpi intake from a GTA on it about 6 months ago. The original intake was warped (po still drove the car with a cracked block til she blowed)
As for using a 305 MEMCAL (this is the '91 in your mini-sig?), the ratio of engine displacement to injector flow is the same between the two engines. So the fueling shouldn't be too far off.
Correct it is the 91. I was just wondering if the 22lb injectors vs the 19lb injectors that come in a 305 would cause it to run rich because the memcal still thinks it has 19lb injectors. But if the flow is the same then I guess the problem is hiding somewhere else.
RBob.
Any chance you also did headers and the O2 sensor is further downstream from the engine? If so that will do it. The O2 cools off and the BLMs head for the sky, adding fuel once in closed loop.
No headers. its the stock manifold
Maybe a new engine, or some new sealants for the intake? That can cause the O2 sensor to go south.
it's a used engine from an old chevy suburban, But I did put (used) 083 heads and tpi intake from a GTA on it about 6 months ago. The original intake was warped (po still drove the car with a cracked block til she blowed)
As for using a 305 MEMCAL (this is the '91 in your mini-sig?), the ratio of engine displacement to injector flow is the same between the two engines. So the fueling shouldn't be too far off.
Correct it is the 91. I was just wondering if the 22lb injectors vs the 19lb injectors that come in a 305 would cause it to run rich because the memcal still thinks it has 19lb injectors. But if the flow is the same then I guess the problem is hiding somewhere else.
RBob.
Junior Member
Joined: Sep 2006
Posts: 44
Likes: 1
From: Littleton, CO
Car: 1988 Camaro w/T Tops
Engine: 305 TBI
Transmission: Borg-Warner 5 spd
Axle/Gears: 3.73
Re: Running rich is this normal?
I've been bumping around strings on various boards looking for a parallel problem with no luck, but one thing I have noticed - your name keeps coming up as a good resource. Please help me get my 88 305 TBI 5 spd car out of its current "paperweight in the garage" status.
I have upgraded my car with 081 heads, Edelbrock intake, Edelbrock headers, high flow cat, three inch cat back exhaust, posi, 3.73 R & P and heated Oxygen sensor. At that time it ran great! In March I installed an L98 hydraulic roller cam and double chain timing gear. The car wouldn't start. I checked distributor placement, valvle adjustment and timing. It seems to be excessively rich. I replaced the CTS and now at least the car starts, but it won't idle and still seems very rich. If I try to restart it once it dies, it won't start and the spark plugs are dripping wet with fuel. Have I surpassed the ECM's capacity to compensate for the mod's I have done? The only codes I get are "12's". Can you please point me in the proper direction? I would greatly appreciate it. If this isn't the correct venue for this question, then please direct me to the proper one. Thanks.
I have upgraded my car with 081 heads, Edelbrock intake, Edelbrock headers, high flow cat, three inch cat back exhaust, posi, 3.73 R & P and heated Oxygen sensor. At that time it ran great! In March I installed an L98 hydraulic roller cam and double chain timing gear. The car wouldn't start. I checked distributor placement, valvle adjustment and timing. It seems to be excessively rich. I replaced the CTS and now at least the car starts, but it won't idle and still seems very rich. If I try to restart it once it dies, it won't start and the spark plugs are dripping wet with fuel. Have I surpassed the ECM's capacity to compensate for the mod's I have done? The only codes I get are "12's". Can you please point me in the proper direction? I would greatly appreciate it. If this isn't the correct venue for this question, then please direct me to the proper one. Thanks.
Last edited by larry88ttops; Jun 6, 2011 at 04:00 PM. Reason: Left out something.
Thread
Thread Starter
Forum
Replies
Last Post
