Hotwire
NAXJA Forum User
- Location
- Spoke, BC, Canada
So, I had a bad engine in my '89. I swapped in an HO motor, did ALL the usual upgrades along with enhanced grounds. Every sensor has less then 1ohm of resistance. Brand new Exhaust manifold, Front pipe and 02 Sensor. All new gaskets and vacuum lines.
With the Snap-On MTG2500 hooked up, I follow the guided testing for all of the parameters.
MAP : Good (1.5- 2v)
IAT : Good (Rises from ambient to about
CTS : Good (Rises from ambient to 86-90c)
TPS : 0.69v
Idle : 680-700 rock solid
02 : Fluctuates between 2.9 - 4.9v (When pumping throttle)
HOWEVER.. The ECU only swaps between open and closed loop on cold start, then pegs the O2 at 4.9v and stays in open loop. The ECU reports a "Lean" fuel situation and I think this is the reason. But why?
I have run a small hose and propane around all the intake flanges and ports with no fluctuation in the idle. Same with the hoses. No vacuum leaks. Which is also supported by the rock solid idle and the MAP.
I cannot hear an exhaust leak, I cannot see one either. I have used a stethoscope to listen, and a cold mirror to check for condensation and look. For the LIFE of me I cannot find the issue, and its costing me $20 to drive 30km. Shes running RICH RICH RICH.
Any suggestions? :badpc:
With the Snap-On MTG2500 hooked up, I follow the guided testing for all of the parameters.
MAP : Good (1.5- 2v)
IAT : Good (Rises from ambient to about
CTS : Good (Rises from ambient to 86-90c)
TPS : 0.69v
Idle : 680-700 rock solid
02 : Fluctuates between 2.9 - 4.9v (When pumping throttle)
HOWEVER.. The ECU only swaps between open and closed loop on cold start, then pegs the O2 at 4.9v and stays in open loop. The ECU reports a "Lean" fuel situation and I think this is the reason. But why?
I have run a small hose and propane around all the intake flanges and ports with no fluctuation in the idle. Same with the hoses. No vacuum leaks. Which is also supported by the rock solid idle and the MAP.
I cannot hear an exhaust leak, I cannot see one either. I have used a stethoscope to listen, and a cold mirror to check for condensation and look. For the LIFE of me I cannot find the issue, and its costing me $20 to drive 30km. Shes running RICH RICH RICH.
Any suggestions? :badpc: