After just converting the 1.8 back to L-Jet the engine is very rich at idle and light load to the point of misfire. It will smooth out under moderate to heavy load. The new FJ6 injectors are suppose to replace B022 906 031C which are listed in AutoAtlanta blow ups. The fuel pressure is right around 37psi. The ECU is correct (473 906 021) for engine code EC 043 518 and the AFM is correct (473 906 301) and newly rebuilt from AA as well. The idle adjust on the AFM could not fix it. It puffs a bit of black smoke sitting at idle.
My next idea is to check the CHT. Any other suggestions?
Full Version: 1.8 L-Jet very rich at idle/light load
fuel pressure should be between 28 and 31 only.
hopefully someone has not changed the camshaft or it will be hopelessly rich!!!!
After just converting the 1.8 back to L-Jet the engine is very rich at idle and light load to the point of misfire. It will smooth out under moderate to heavy load. The new FJ6 injectors are suppose to replace B022 906 031C which are listed in AutoAtlanta blow ups. The fuel pressure is right around 37psi. The ECU is correct (473 906 021) for engine code EC 043 518 and the AFM is correct (473 906 301) and newly rebuilt from AA as well. The idle adjust on the AFM could not fix it. It puffs a bit of black smoke sitting at idle.
My next idea is to check the CHT. Any other suggestions?
QUOTE(rbzymek @ May 24 2019, 02:06 PM) 
After just converting the 1.8 back to L-Jet the engine is very rich at idle and light load to the point of misfire. It will smooth out under moderate to heavy load. The new FJ6 injectors are suppose to replace B022 906 031C which are listed in AutoAtlanta blow ups. The fuel pressure is right around 37psi. The ECU is correct (473 906 021) for engine code EC 043 518 and the AFM is correct (473 906 301) and newly rebuilt from AA as well. The idle adjust on the AFM could not fix it. It puffs a bit of black smoke sitting at idle.
My next idea is to check the CHT. Any other suggestions?
QUOTE(dr914@autoatlanta.com @ May 24 2019, 04:37 PM)
hopefully someone has not changed the camshaft or it will be hopelessly rich!!!!
QUOTE(rbzymek @ May 24 2019, 02:06 PM)
After just converting the 1.8 back to L-Jet the engine is very rich at idle and light load to the point of misfire. It will smooth out under moderate to heavy load. The new FJ6 injectors are suppose to replace B022 906 031C which are listed in AutoAtlanta blow ups. The fuel pressure is right around 37psi. The ECU is correct (473 906 021) for engine code EC 043 518 and the AFM is correct (473 906 301) and newly rebuilt from AA as well. The idle adjust on the AFM could not fix it. It puffs a bit of black smoke sitting at idle.
My next idea is to check the CHT. Any other suggestions?
Why would the cam (if it was changed) cause a rich condition?
QUOTE(rbzymek @ May 24 2019, 06:16 PM)
QUOTE(dr914@autoatlanta.com @ May 24 2019, 04:37 PM)
hopefully someone has not changed the camshaft or it will be hopelessly rich!!!!
QUOTE(rbzymek @ May 24 2019, 02:06 PM)
After just converting the 1.8 back to L-Jet the engine is very rich at idle and light load to the point of misfire. It will smooth out under moderate to heavy load. The new FJ6 injectors are suppose to replace B022 906 031C which are listed in AutoAtlanta blow ups. The fuel pressure is right around 37psi. The ECU is correct (473 906 021) for engine code EC 043 518 and the AFM is correct (473 906 301) and newly rebuilt from AA as well. The idle adjust on the AFM could not fix it. It puffs a bit of black smoke sitting at idle.
My next idea is to check the CHT. Any other suggestions?
Why would the cam (if it was changed) cause a rich condition?
Cam overlap will cause the air flow meter to flutter, causing a rich condition at idle.
QUOTE(ndfrigi @ May 24 2019, 03:23 PM)
fuel pressure should be between 28 and 31 only.
I think I need to reduce the pressure to lean it out but the Haynes manual specifies 35.7 psi.
Get an A/F meter and adjust the AFM or take it to a competent shop and have them adjust it based on the mixture.
Out of the box AFM even if rebuilt is likely the culprit, I had the same issue with one rebuilt by a competent shop as well as a NOS one.
Out of the box AFM even if rebuilt is likely the culprit, I had the same issue with one rebuilt by a competent shop as well as a NOS one.
QUOTE(echocanyons @ May 24 2019, 11:54 PM)
Get an A/F meter and adjust the AFM or take it to a competent shop and have them adjust it based on the mixture.
Out of the box AFM even if rebuilt is likely the culprit, I had the same issue with one rebuilt by a competent shop as well as a NOS one.
Thank you for the suggestion. I have a Triad on order with a bung. In the meantime I will make an adjustment and see if I can get it to drive better.
QUOTE(rbzymek @ May 25 2019, 06:26 AM)
QUOTE(echocanyons @ May 24 2019, 11:54 PM)
Get an A/F meter and adjust the AFM or take it to a competent shop and have them adjust it based on the mixture.
Out of the box AFM even if rebuilt is likely the culprit, I had the same issue with one rebuilt by a competent shop as well as a NOS one.
Thank you for the suggestion. I have a Triad on order with a bung. In the meantime I will make an adjustment and see if I can get it to drive better.
So the root cause of the rich condition was that I incorrectly wired the AFM when I fabricated the new L-Jet harness. The wires were flipped end to end in the 7 way connector. The car runs great now. Just waiting for the AFR meter so I can dial it in. New Pertronix dizzy goes in later today.
Ray
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