v6 Splutters and dies after major work, lambda?
Hi all. Just last week I put my engine together - here's a little history (sorry for massive post, but at least the facts are all down):
Cracked cyl liner last summer, changed with front head gasket and had running last december but couldn't get rear exhaust manifold back on. Engine seemed to run sweet, but couldn't hear much due to exhuast not being connected. Also engine management light was on but I wasn't worried, as lambda must have been getting completly incorrect signal.
Anyway, did the rear head and put it all back together last week. Engine starts but splutters and dies. If I use the accelerator I can keep it going, but it runs very rough until 2000 rpm, when it suddenly screams and sorts itself out. Also after running for about 2 mins the engine management light cleared.
At first I suspected this was due to a missing oil breather which feeds into the air intake after maf but before throttle body. However I have sealed both ends, and engine splutters a little less but still doesn't run right under 2k.
Someone on another board said she had the exact same symptoms when her lambda went. I have a funny feeling that may be correct. I know that ecu's ignore lambda on wide open throttle, and maybe on heavy throttle, but do they also ignore after x amount of revs?
Also would a bad lambda trigger the engine management light?
I doubt its a leak between maf to throttle body as the car runs nearly the same if the pipe on the throttle body is removed except the engine light flickers on and off.
As I ran the car previously without rear exhaust manifold in december, car was running extremely rich, is it possible this rich mixture was igniting in the exhaust and burnt out my lambda, and if so, I'm probably looking at a new cat as well?
Thankfully mine is a very early v6 and I'm pretty sure it only has one lambda.