- Location
- Richardson, TX
any check engine lights?
Nope. This thing has never thrown a CEL lol
O2 sensor, or lack of electrical power to the thermal resistor in the O2 sensor causes open loop/closed loop confusion at idle. Sensor is too cold at idle to work right with out that heater working. It can be tested like a resistor, and test for the power to it from the O2 heater relay.
Tiny easy to miss loose hose on tube, and crack tubing is very easy to miss on the run to the MAP sensor (fire wall on yours????) Or attached the manifold, in which case (its hidden under the MAP) it may be leaking there.
Cracked manifolds can drive a good O2 sensor and ECU nuts and force them to switch to open loop-gas guzzling mode.
I am now a firm believer in crusier 54's Dizzy indexing fine tuning mod!!!! And in checking for issues with the Cap rotor, and Dizzy shaft bearings and for slop side to side and rationally. I almost pulled and scrapped an engine, that turned out to be a failing 2 cent rolled sheer pin holding the drive gear on the shaft on mine. The symptoms started out small and got worse over the weeks.
Also check the Vac line at the FPR nipple to see if the FPR is leaking fuel into the Vac line!!!! And for fun make sure none of the fuel injector wires or plug wires got swapped like 3+4 plug wires in any recent work, LOLOL.
Check the plugs business ends for signs of all or just 1 plug being lean or rich, or oil fouled!!!!
Thanks for the info! Will check these out this weekend!