1993 Corvette running lean code #44
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From: RI
1993 Corvette running lean code #44
My check engine light came on and the car was running a little rough and the exhaust smelled different than usual. Upon pulling the code # 44 that is a left bank O2 sensor. I took it to my mechanic who is very well knowledges with C 4 corvettes. He advised me he replaced the left and right bank 02 sensors. He changed the right because they are not expensive and wanted to make them equal. The vehicle still ran like it did originally and still pulling the 44 code. He advised me it may be the computer having a problem due to the fact he reset the computer and it's still pulling the code. Their computer is saying that the cars ECM is still realising there is a problem so the mechanic thinks its the ECM. All other options were looked at such as EGR, Vacuum leak. Has anyone had this problem and will a new ECM rectify the problem. My mechanic says it will
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From: Glenbeulah Wi
Code 44 can also be set when there is a miss, the high levels of oxygen dumped into the exhaust due to incomplete combustion trick the computer into thinking it is lean, Have you mechanic check for a cylinder miss and fix that problem if it exists.
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So, counterintuitively, that lean error could be causing the engine overall to run much richer.
What I'd do is first, Ohm out the injectors at cold temp before running the engine. Generally these things should be around 16 to 18 Ohms. Then come back after the engine is fully warmed up and Ohm them out again. If there's a faulty injector, it may show an out-of-family resistance value from the others.
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From: RI
So this week I decided to change the fuel filter and the injectors. I tested the current injectors with an OHMS meter and there were several inconsistencies with the highest reading being 12.5. The fuel filter I had my mechanic change due to not having a lift, the injectors I did myself with Accel 23 lb. injectors. What a difference in the performance and idle of the vehicle, I have not gotten an SES light yet but maybe to early yet due to the codes being cleared when the battery was disconnected for the injector change. The mechanic thinks it may have been the original fuel filter could not get air through it. The injector job is not that difficult on these cars its remembering to re connect the numerous items you had to disconnect to get at the fuel rail. I want to thank everyone for their input, so far so good, I will advise for an SES light and my run a code check this week.
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From: RI
Runs 100% better with the new injectors and fuel filter but there is still a little roughness when idle or traveling at a higher speed. The SES light came on again with the same #44 code. I checked the spark plugs and they look like the original's corvette only has 58k miles. I ordered new plugs and will be putting them in this week. What a pain in the *** that is going to be. I'm also thinking of checking the pressure in the fuel pressure regulator. I am also contemplating on changing the water pump and opti spark and plug wires. Any other thoughts.
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From: RI
So all of the above posts have still caused the SES light to go on but it only does it on idle for an extensive amount of time, such as red light, traffic but once you get going it goes off. The injectors have been changed, spark plugs, fuel filter and the left and right O2 sensors due to code # 44. SES light is not as frequent as before, as I said only comes on during idle in traffic once you get going it goes away. I think I will check the fuel pressure next. My mechanic thinks its the ECM because they replaced the o2 sensors and still got the 44 code.
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From: Orlando FL
Check for a vacuum leak. Might need to do a smoke test for this problem.
Also check the EGR to see if if it seals properly. might have to remove it to get a good check. Might have carbon build up.
Also check the EGR to see if if it seals properly. might have to remove it to get a good check. Might have carbon build up.
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From: Glenbeulah Wi
So all of the above posts have still caused the SES light to go on but it only does it on idle for an extensive amount of time, such as red light, traffic but once you get going it goes off. The injectors have been changed, spark plugs, fuel filter and the left and right O2 sensors due to code # 44. SES light is not as frequent as before, as I said only comes on during idle in traffic once you get going it goes away. I think I will check the fuel pressure next. My mechanic thinks its the ECM because they replaced the o2 sensors and still got the 44 code.
One other thought is there any way the sensor is staying too cold, at idle the exhaust temp is less and it is possible that the sensor cools off and reads incorrectly It would be nice to put a scanner on the car and actually see what the sensor is doing..
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From: RI
I replaced the injectors two weeks ago had all ohm inconsistencies. New injectors Accels cold are consistently 14.5 ohms and runs much better. Just replaced plugs also with NGK and the Fuel filter was changed. 02 sensors were replaced. Replaced both even though the 44 code is left bank lean. How do you check for a cylinder miss fire?