bank 1 rich bank 2 ok
Posted: 2021 Jul 12, 21:26
92 mustang N/A 408" efi a9l2. Super victor efi 80lb siemens deka (genuine), 10.5:1 93 octane pump fuel. 6061 elbow 90mm TB 4" anderson pipe. PCV is more or less the factory style setup. AFR205 renegades. Ed cam 242-252 at 50 .600+ lift. Pretty common setup.
WBO2 is in the driver's side of the H pipe about 6" behind the collector. right bank (bank 1) plugs show to be really rich. They are black carbon fouled, I have not been wide open with these plugs and they have about 200 miles or so on them, max. Left side plugs look great. HEGO's have a bias but only at certain throttle opening. At 1/4 throttle the hego's show about the same. Just off of idle, CL, the right side shows 1.25+ lambda, left side 0.98-1.02 for the most part. It almost follows high vacuum, which led me to believe that it had a vacuum leak somewhere. But darned if I can find it even with smoke machine. Even went as far as putting 10 psi into the intake tract and using soapy water around the intake, injectors, everything post throttle body and nothing was found, zero leaks. Not even the throttle shaft or TPS which are pretty common.
Smoke tested the intake, zero leaks. I bought a smoke machine to do this before I had to go out of town last year. Re-tested earlier to verify my notes. Engine compression 180 psi on all 8 cylinders hot. 175 cold. The ONLY thing I have found is some real small leaks at the right side header slip fit tubes, and a teeny tiny leak at the flange. I went in and made some makeshift clamps to go around the slip fits and got those sealed up but the flange, nothing I can do about that short of replacing the headers. I didn't like this design from the get-go anyway.
Several questions. Do you reckon the elbow might have something to do with it? I wouldn't think so at low load high vacuum but what do I know? Second thought was PCV. Valve is in front left side of valve cover. Fresh air tube in the left rear valve cover, runs up to the intake tube almost like factory 5.0's were but I used a larger 3/8 dia tube and hose. It's all sealed up good verified with smoke test. Will a tiny flange leak cause the hego's to read lean, and then that side of the motor to go "that" rich? It runs like crap, as if it were real lean but the o2's don't show it. KAMs can get 1.25+ on the right side and stays 1.00-ish on the left side, but again only under really light load and high vacuum. The less vacuum, the closer the KAM's get. At about 1/4 throttle give or take a little they are about equal side to side.
It has fought me for the last year and I'm honestly about ready to throw in the towel. I put a lot of my money into it so it's kinda frustrating.
Ideas?
WBO2 is in the driver's side of the H pipe about 6" behind the collector. right bank (bank 1) plugs show to be really rich. They are black carbon fouled, I have not been wide open with these plugs and they have about 200 miles or so on them, max. Left side plugs look great. HEGO's have a bias but only at certain throttle opening. At 1/4 throttle the hego's show about the same. Just off of idle, CL, the right side shows 1.25+ lambda, left side 0.98-1.02 for the most part. It almost follows high vacuum, which led me to believe that it had a vacuum leak somewhere. But darned if I can find it even with smoke machine. Even went as far as putting 10 psi into the intake tract and using soapy water around the intake, injectors, everything post throttle body and nothing was found, zero leaks. Not even the throttle shaft or TPS which are pretty common.
Smoke tested the intake, zero leaks. I bought a smoke machine to do this before I had to go out of town last year. Re-tested earlier to verify my notes. Engine compression 180 psi on all 8 cylinders hot. 175 cold. The ONLY thing I have found is some real small leaks at the right side header slip fit tubes, and a teeny tiny leak at the flange. I went in and made some makeshift clamps to go around the slip fits and got those sealed up but the flange, nothing I can do about that short of replacing the headers. I didn't like this design from the get-go anyway.
Several questions. Do you reckon the elbow might have something to do with it? I wouldn't think so at low load high vacuum but what do I know? Second thought was PCV. Valve is in front left side of valve cover. Fresh air tube in the left rear valve cover, runs up to the intake tube almost like factory 5.0's were but I used a larger 3/8 dia tube and hose. It's all sealed up good verified with smoke test. Will a tiny flange leak cause the hego's to read lean, and then that side of the motor to go "that" rich? It runs like crap, as if it were real lean but the o2's don't show it. KAMs can get 1.25+ on the right side and stays 1.00-ish on the left side, but again only under really light load and high vacuum. The less vacuum, the closer the KAM's get. At about 1/4 throttle give or take a little they are about equal side to side.
It has fought me for the last year and I'm honestly about ready to throw in the towel. I put a lot of my money into it so it's kinda frustrating.
Ideas?