Is that an OBD1 vehicle?
It’s actually 96 the 1st OBDII vehicle. Only the minimum required OBDII is present.
I just helped get a 99 Taurus started after 2 or 3 years of sitting and it has started running badly in the same way. At first it ran fine but then after a while it starts acting like it’s going to stall and then the engine speeds back up to normal idle over and over. No CEL. I suspect oxygen sensors. It seems to run fine when under load. I’ll have to experiment some more before drawing any more conclusions.
I suspect varnish in the injectors…
If the gasoline is 3 years old, don’t expect the engine to run well. If there is a problem, you will need to drive the vehicle for about 10 miles for a fuel trim to reach a threshold point to set a fault.
I think p0443 means the computer has detected a problem w/ the purge control valve circuit. That circuit is supposed to have a certain known resistance range, and instead it is measuring the resistance outside that range. Usually this is caused by an open circuit. Either a wire has broken, connector is loose or corroded, or purge valve itself is faulty.
Purge valve is part of evap control system. Gasoline fumes in the gas tank are routed to and stored in canister, purge valve closed. Later an engine operation condition that’s favorable to burning the gasoline in the canister occurs, then the computer opens the purge valve, and gasoline fumes get burned in the engine. The purge valve is a electro-magnet controlled solenoid, so is either on or off. Apparently on your engine the purge valve opens & closes in a programmed sequence, the % open proportional to how much purge flow is desired. More purge when air flow into engine is higher, less when airflow to engine is less.
Purge valve failure is pretty common complaint here, on many make/models. If it fails in closed position, can cause gasoline to build up in canister, eventually making it difficult to fill gas tank, pump will keep shutting off. If purge valve was stuck in the open position it could cause an overly rich mixture. When that happens owner often find the engine takes a little longer to start than normal when hot, esp after re-filling the gas tank. Suggest to monitor for this code, and repair purge valve/circuit/ECM if code remains.
Note: Good idea w/this code to also check evap pressure sensor, vent valve, canister, and evap system hoses.
I have a car and a truck for over 10 years with a little soot at the tailpipe and neither one uses a measureable amount of oil.
I hadn’t thought that Snowman’s posts could possibly become less fact-based, or more bizarre, but now he/she has proved me wrong.
This is how I’ve avoided buying an oil burning used car for the last 30+ years.
Quick check of the tailpipe.
Had to adjust my routine this last time since a little dry soot is okay with GDI.
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When I look at used cars, the only one I will buy is one with a tan exhaust, not black. Comes from pre catalytic days, but still my preference.
Well it’s not always possible to for the vehicle to know if an oxygen sensor is malfunctioning. If you buy a defective after market oxygen sensor and it makes your engine run too lean or to rich, it won’t trigger a code unless it’s very innacurate. Without a second oxygen sensor to compare to there is no way it can know that the sensor isn’t accurate. A bad oxygen sensor is detected by the expected failure mode of becoming slow to respond. If it somehow fails in a different way then the vehicle won’t always know that it’s bad.
Lean and rich faults are determined by fuel trim deviation from baseline. These faults can take 10 to 20 minutes of driving to be detected.