Alright so my 86 5.0 Regal is running rich,it is throwing a 45 Code,I replaced the carb new and a new bosch o2 sensor,but still it says the car runs rich.I have no check engine light untill i hit over 60mph and then it turns off when i go below 60mph,so what could it be?Oh yeah,I also hollowed out my cat for more power,but it was throwing a rich code before i did it.
Have a Engine Code 45 Running Rich,how to fix?
- Thread starter 86laidlow
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86laidlow said:
So first question, is this a 307 Olds motor or a 305 Chevy? Besides hollowing out the cat, what else have you done to it? Was the new carb properly adjusted following the factory procedure when it was installed?
Also, how do you know it's a Code 45? Is there a stored code? If so, then the Check Engine light should be on whenever there's a stored code, so that would indicate another problem. If there is no stored code, where did you read the Code 45?
I've had a problem with the Check Engine light coming on at high speeds then turning off again at low speeds. It turned out to be low coolant that caused the temp sensor to be uncovered and give a false reading. This would cause the computer to think the engine was cold and richen the mixture. For some reason the 307 is very difficult to bleed all the air out of the cooling system. I've owned Oldsmobiles for 35 years and the 307 is the only Olds motor that seems to have this problem.
re
The engine is a307 olds with the 7a heads.The code is stored,but,the check engine light only comes on at high speeds and turns back off at low speeds.I know its a 45 code because i hooked it up to my scanner and thats what it tells me.It does seem like it would be the problem you described,but i dont know,sometimes it leaks a little coolant
The engine is a307 olds with the 7a heads.The code is stored,but,the check engine light only comes on at high speeds and turns back off at low speeds.I know its a 45 code because i hooked it up to my scanner and thats what it tells me.It does seem like it would be the problem you described,but i dont know,sometimes it leaks a little coolant
Since the carb has been rebuilt you may have the same problem I did with a code 45 on my old '84 SS. I always got a code 45 on the highway and to make a long story short the guy who rebuilt it didn't set the MCS rich/lean stops anywhere near where they should have been. I moved both the lean and rich stops down about a 1/8 turn at a time until it went away and never had a problem after that. The needle wasn't allowed enough travel downwards to block enough of the excessive fuel that was pouring in.
The ECM gets a rich signal from the 02, can't correct it by leaning out the MCS as much as possible (was at 100% duty cycle on the highway), so it throws a rich code. If you have a scanner, watch the duty cycle of the MCS on the highway (when the code would come on), and this should help you see what's going on.
The ECM gets a rich signal from the 02, can't correct it by leaning out the MCS as much as possible (was at 100% duty cycle on the highway), so it throws a rich code. If you have a scanner, watch the duty cycle of the MCS on the highway (when the code would come on), and this should help you see what's going on.
re
I have cleared the code before and it comes back,the carb is a little high at idlle,it has a rochester 4 barrel carb with electric chocke(or computer controlled).The carb is new and i purchased it from an old guy who has been working on carbs for 20 years with a shop and he said he set things up to factory specs,but he could have messed up.anyway,how do i richen the carb?its an aftermarket carb so i think it has the mixtures screws covered,but i dont know where they are.
I have cleared the code before and it comes back,the carb is a little high at idlle,it has a rochester 4 barrel carb with electric chocke(or computer controlled).The carb is new and i purchased it from an old guy who has been working on carbs for 20 years with a shop and he said he set things up to factory specs,but he could have messed up.anyway,how do i richen the carb?its an aftermarket carb so i think it has the mixtures screws covered,but i dont know where they are.
I assume this is a CCC Q-jet? It wouldn't be new as no Q-jets are made new anymore. It would be a rebuild with all new parts. It's the MCS rich/lean stops you would need to adjust, which requires special tools - if you don't have these tools I would see if the guy who rebuilt it can adjust the stops for you.
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Yeah,it is not an original quadra,just an aftermarket with brand new parts,i cant have the guy i got it from adjust it because i got it online.I have little specialty tools i can probale use,i would just need to see what it the adjustment screws look like to see if i can do it myself,but i need to know where they are located.
Yeah,it is not an original quadra,just an aftermarket with brand new parts,i cant have the guy i got it from adjust it because i got it online.I have little specialty tools i can probale use,i would just need to see what it the adjustment screws look like to see if i can do it myself,but i need to know where they are located.
See #72 & #226 here:
http://dyeager535.topcities.com/CCCqjetdiagram.html
Here's the CCC-specific tools you will need:
http://thexton.com/index.cfm/pageid/24
(Kit #350)
I would suggest Doug Roe's Q-jet book - it's a great reference if you plan to make adjustments and/or rebuild your own carb.
http://dyeager535.topcities.com/CCCqjetdiagram.html
Here's the CCC-specific tools you will need:
http://thexton.com/index.cfm/pageid/24
(Kit #350)
I would suggest Doug Roe's Q-jet book - it's a great reference if you plan to make adjustments and/or rebuild your own carb.
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