My slant six is having a persistent issue. It idles very rough (on three cylinders) but drives very very smooth. Black soot out the exhaust and strong gas smell when idling only. I am fouling plugs with carbon constantly.
When I hook up a timing light, cylinder 1,2 and 4 have a very random/unsteady firing while the others 3,5,6 are steady consistent. When revved, all cylinders have a good consistent firing.
I’ve replaced the cap and rotor with two new sets, the plug wires three times and spark plugs countless times experimenting with wider and narrower gaps. I also replaced the coil with a new one. I purchased a new battery as well. I completely disassembled and rebuilt the carburetor. Valve lash done to spec three times with engine hot. Fuel vapor mod completed with new tank and all new R12 gas lines and good filter.
What am I missing? Could it be a bad distributor? My car is a stock 1976 slant 6. Still running ignition factory parts except what I mentioned above. I’m thinking something is up with the ignition. Originally I though maybe a carb issue running too rich and fouling plugs, but now I’m thinking ignition.
Any ideas? Thanks for your help.
When I hook up a timing light, cylinder 1,2 and 4 have a very random/unsteady firing while the others 3,5,6 are steady consistent. When revved, all cylinders have a good consistent firing.
I’ve replaced the cap and rotor with two new sets, the plug wires three times and spark plugs countless times experimenting with wider and narrower gaps. I also replaced the coil with a new one. I purchased a new battery as well. I completely disassembled and rebuilt the carburetor. Valve lash done to spec three times with engine hot. Fuel vapor mod completed with new tank and all new R12 gas lines and good filter.
What am I missing? Could it be a bad distributor? My car is a stock 1976 slant 6. Still running ignition factory parts except what I mentioned above. I’m thinking something is up with the ignition. Originally I though maybe a carb issue running too rich and fouling plugs, but now I’m thinking ignition.
Any ideas? Thanks for your help.