car running rich ?????????1994 C4
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Joined: Apr 2013
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From: Wyle Texas
car running rich ?????????1994 C4
Well hear goes the run down . The car keeps setting the check engine light . At first I thought I had an injector sticking open dumping fuel. but listened to the injector pulse and they all sound even and running with in the norm ? I forgot how to do the pin trick for obd1 , but I find it somewhere I am sure . Has anyone had a similar incident . Could it be a fuel regulator ? I have just done the dreaded opti spark , new plugs , wires the works . wasn't happy with the cheap coil wanted an MSD but whatever . Anyway Help , lol. WTF ???????????? It has to be something simple hope I can figure it out before it ruins the catalytic converter .
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From: SANTA CRUZ CA
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From: Charlotte NC
YEP...I fix problems like this often.
First off...without a scanner you are chasing your tail. The information on the scanner will direct you to an area(s) that MAY NOT set a code.
Like mentioned by "65 Drivr". The O2 sensor(s) can be at fault...and checking them on how they are working may require a scanner so you can watch the mV readings.
Did you Ohm out the new wires and make sure that they are/were OK...I have had new wires that were not right and needed replacing or repair to get them to Ohm out correctly.
When you replaced the Opti-spark and parts. Where they all GM/AC Delco or from someone else??? Did you use AC Delco spark plugs with the platinum tips that were gapped to .050"??? I sometimes use other makes of ignition parts...but it is usually being tested/run on a dyno to verify any changes in performance....and the engines are often times upgrade from stock.
Vacuum leaks???
What is your fuel pressure??? Not running and running??? Does the fuel pressure hold when the engine is turned off and stay for a while...or does it drop like a rock.
How many miles on the engine??? Fuel injectors when over 70K get a balance test performed on them at my shop due to the failure rate increased after 70K. Regardless of the sound they make...if they are not balanced...you can have a rough idle and or other problems due to which ever injector is "bad" may be not atomizing the fuel under pressure like the others ...thus sending a more raw fuel mix to the cylinder.
Raw or liquid fuel being dumped into the cylinders that can not be burned off due to bad ignition components allow un-burnt fuel being exhausted...and this fuel is thus keeping the O2 sensor(s) from being allowed to heat up and turn your ECM on and get out of "open-loop" and go into "closed-loop". If you car is at operation temperature (180+ degree's) and you are NOT in closed loop...you have a problem. Your system should allow the ECM to go into closed loop a few minutes after starting it up....IF it does go into "closed-loop"...and then goes back into "open-loop" you do have a issue due to excessive fuel being able to be dumped into the cylinder....thus cooling off the O2 sensor(s) and switching the ECM to "open-loop". I know you have heated O2 sensors in your car....but that is assuming that the circuit is operating and you do not have an electrical issue and the heater is not working...so this excessive fuel can/could effect things even further.
Like mentioned by a previous post. You need to find out what code is coming up first.
DUB
First off...without a scanner you are chasing your tail. The information on the scanner will direct you to an area(s) that MAY NOT set a code.
Like mentioned by "65 Drivr". The O2 sensor(s) can be at fault...and checking them on how they are working may require a scanner so you can watch the mV readings.
Did you Ohm out the new wires and make sure that they are/were OK...I have had new wires that were not right and needed replacing or repair to get them to Ohm out correctly.
When you replaced the Opti-spark and parts. Where they all GM/AC Delco or from someone else??? Did you use AC Delco spark plugs with the platinum tips that were gapped to .050"??? I sometimes use other makes of ignition parts...but it is usually being tested/run on a dyno to verify any changes in performance....and the engines are often times upgrade from stock.
Vacuum leaks???
What is your fuel pressure??? Not running and running??? Does the fuel pressure hold when the engine is turned off and stay for a while...or does it drop like a rock.
How many miles on the engine??? Fuel injectors when over 70K get a balance test performed on them at my shop due to the failure rate increased after 70K. Regardless of the sound they make...if they are not balanced...you can have a rough idle and or other problems due to which ever injector is "bad" may be not atomizing the fuel under pressure like the others ...thus sending a more raw fuel mix to the cylinder.
Raw or liquid fuel being dumped into the cylinders that can not be burned off due to bad ignition components allow un-burnt fuel being exhausted...and this fuel is thus keeping the O2 sensor(s) from being allowed to heat up and turn your ECM on and get out of "open-loop" and go into "closed-loop". If you car is at operation temperature (180+ degree's) and you are NOT in closed loop...you have a problem. Your system should allow the ECM to go into closed loop a few minutes after starting it up....IF it does go into "closed-loop"...and then goes back into "open-loop" you do have a issue due to excessive fuel being able to be dumped into the cylinder....thus cooling off the O2 sensor(s) and switching the ECM to "open-loop". I know you have heated O2 sensors in your car....but that is assuming that the circuit is operating and you do not have an electrical issue and the heater is not working...so this excessive fuel can/could effect things even further.
Like mentioned by a previous post. You need to find out what code is coming up first.
DUB
Pro
Joined: Aug 2012
Posts: 663
Likes: 1
From: Nashville TN
Mine kept setting codes for lean on left bank while emissions test said way too rich. Chased my tail with EGR, vac leaks, everything. Checked plugs and they were black so I swapped out both O2 sensors and my car turned into a beast. It has never run better.
I think they were incorrectly sensing lean and adding way too much fuel.
I think they were incorrectly sensing lean and adding way too much fuel.
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Advanced
Joined: Apr 2013
Posts: 63
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From: Wyle Texas
Looked in to it a bit
YEP...I fix problems like this often.
First off...without a scanner you are chasing your tail. The information on the scanner will direct you to an area(s) that MAY NOT set a code.
Like mentioned by "65 Drivr". The O2 sensor(s) can be at fault...and checking them on how they are working may require a scanner so you can watch the mV readings.
Did you Ohm out the new wires and make sure that they are/were OK...I have had new wires that were not right and needed replacing or repair to get them to Ohm out correctly.
When you replaced the Opti-spark and parts. Where they all GM/AC Delco or from someone else??? Did you use AC Delco spark plugs with the platinum tips that were gapped to .050"??? I sometimes use other makes of ignition parts...but it is usually being tested/run on a dyno to verify any changes in performance....and the engines are often times upgrade from stock.
Vacuum leaks???
What is your fuel pressure??? Not running and running??? Does the fuel pressure hold when the engine is turned off and stay for a while...or does it drop like a rock.
How many miles on the engine??? Fuel injectors when over 70K get a balance test performed on them at my shop due to the failure rate increased after 70K. Regardless of the sound they make...if they are not balanced...you can have a rough idle and or other problems due to which ever injector is "bad" may be not atomizing the fuel under pressure like the others ...thus sending a more raw fuel mix to the cylinder.
Raw or liquid fuel being dumped into the cylinders that can not be burned off due to bad ignition components allow un-burnt fuel being exhausted...and this fuel is thus keeping the O2 sensor(s) from being allowed to heat up and turn your ECM on and get out of "open-loop" and go into "closed-loop". If you car is at operation temperature (180+ degree's) and you are NOT in closed loop...you have a problem. Your system should allow the ECM to go into closed loop a few minutes after starting it up....IF it does go into "closed-loop"...and then goes back into "open-loop" you do have a issue due to excessive fuel being able to be dumped into the cylinder....thus cooling off the O2 sensor(s) and switching the ECM to "open-loop". I know you have heated O2 sensors in your car....but that is assuming that the circuit is operating and you do not have an electrical issue and the heater is not working...so this excessive fuel can/could effect things even further.
Like mentioned by a previous post. You need to find out what code is coming up first.
DUB
First off...without a scanner you are chasing your tail. The information on the scanner will direct you to an area(s) that MAY NOT set a code.
Like mentioned by "65 Drivr". The O2 sensor(s) can be at fault...and checking them on how they are working may require a scanner so you can watch the mV readings.
Did you Ohm out the new wires and make sure that they are/were OK...I have had new wires that were not right and needed replacing or repair to get them to Ohm out correctly.
When you replaced the Opti-spark and parts. Where they all GM/AC Delco or from someone else??? Did you use AC Delco spark plugs with the platinum tips that were gapped to .050"??? I sometimes use other makes of ignition parts...but it is usually being tested/run on a dyno to verify any changes in performance....and the engines are often times upgrade from stock.
Vacuum leaks???
What is your fuel pressure??? Not running and running??? Does the fuel pressure hold when the engine is turned off and stay for a while...or does it drop like a rock.
How many miles on the engine??? Fuel injectors when over 70K get a balance test performed on them at my shop due to the failure rate increased after 70K. Regardless of the sound they make...if they are not balanced...you can have a rough idle and or other problems due to which ever injector is "bad" may be not atomizing the fuel under pressure like the others ...thus sending a more raw fuel mix to the cylinder.
Raw or liquid fuel being dumped into the cylinders that can not be burned off due to bad ignition components allow un-burnt fuel being exhausted...and this fuel is thus keeping the O2 sensor(s) from being allowed to heat up and turn your ECM on and get out of "open-loop" and go into "closed-loop". If you car is at operation temperature (180+ degree's) and you are NOT in closed loop...you have a problem. Your system should allow the ECM to go into closed loop a few minutes after starting it up....IF it does go into "closed-loop"...and then goes back into "open-loop" you do have a issue due to excessive fuel being able to be dumped into the cylinder....thus cooling off the O2 sensor(s) and switching the ECM to "open-loop". I know you have heated O2 sensors in your car....but that is assuming that the circuit is operating and you do not have an electrical issue and the heater is not working...so this excessive fuel can/could effect things even further.
Like mentioned by a previous post. You need to find out what code is coming up first.
DUB
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Joined: Apr 2013
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From: Wyle Texas
Ithink your on to some thing !!!
Mine kept setting codes for lean on left bank while emissions test said way too rich. Chased my tail with EGR, vac leaks, everything. Checked plugs and they were black so I swapped out both O2 sensors and my car turned into a beast. It has never run better.
I think they were incorrectly sensing lean and adding way too much fuel.
I think they were incorrectly sensing lean and adding way too much fuel.
Thread Starter
Advanced
Joined: Apr 2013
Posts: 63
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From: Wyle Texas
And you would be right
I had a lean code in my left bank o2 sensor . Replaced it and wow its a new car . Funny thing is it was a factory part so it was kind of cool that it had mad it this far . I am replacing the other side so its all balanced . sure it OE too.
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Joined: Apr 2013
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From: Wyle Texas
It's doing it again except this time it is a H44 code and a stupid low pulse 16 code
Wtf is wrong with these cars are they ****ing possessed or really that much of a piece of ****.
Sorry really ****ing mad with this car right now.
Just did the damn opti with plugs wired the works less than 6,500 miles ago and replaced the o2 sensor 3 months ago now it's fouled again. I mean really , are you ****ing kidding me
All I do is show this car love and it runs great most the time but damn it has its moments like this make me want to slap a for sale sign on it every other month or so when it decides to be a bitch
Wtf is wrong with these cars are they ****ing possessed or really that much of a piece of ****.
Sorry really ****ing mad with this car right now.
Just did the damn opti with plugs wired the works less than 6,500 miles ago and replaced the o2 sensor 3 months ago now it's fouled again. I mean really , are you ****ing kidding me
All I do is show this car love and it runs great most the time but damn it has its moments like this make me want to slap a for sale sign on it every other month or so when it decides to be a bitch