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There is a faulty assumption going on here. The OP depressed the schraders and found pressure. That does not necessarily mean that there is refrigerant in the system. Since a shop has previously worked on the system, it is quite possible that the system was empty, and that the technician pressurized it slightly with nitrogen to check for leaks, which is a very common practice. A small leak will have a allowed the refrigerant to leak out over time, but there has not been enough time for the nitrogen to leak out yet. The compressor will stop turning on below a certain PSI. This means there will still be pressure in the system, but not enough to energize the compressor. Without gauges, there is no way to know how much (or how little) pressure there is in the system. There is also no way for the OP to verify what gasses are actually in the system. I would strongly recommend having a shop repair this system.
The purpose of the LTFT is to keep the STFT near 0 to allow for the computer to oscillate lean/rich to feed the catalytic converter. The catalytic has two clearing beds in it. One bed needs CO for its chemical reaction to work, the other needs O2 for its chemical reaction to work. The computer oscillates the mixture between slightly lean and slightly rich so that the cat has the gasses it needs to do its job. A narrow band (usually Zirconium) O2 sensor is used for this job. These sensors should oscillate between 100 and 900 millivolts ideally, and between 250 and 750 millivolts is commonly observed. The point is they should constantly be moving back and forth in closed loop. On older vehicles, a second narrow band O2 sensor was used to measure the output gasses to monitor the efficiency of the cat and let the computer know that the engine management strategy was working. Newer vehicles employ a wide band sensor (also called an air-fuel ratio sensor) for this purpose. The purpose of the STFT is to add or subtract fuel to the engine to attempt to maintain its stoichiometric ratio of 14.7 parts air to 1 part fuel. When the STFT goes positive, this indicates a lean signal from the O2 sensor, which causes the computer to add fuel to the fuel mixture (make it richer). When the STFT goes negative, this indicates a rich signal from the O2 sensor, which causes the computer to reduce fuel (make the mixture leaner). A LTFT of +/- 10% is generally not a worry, and is perfectly normal for cars more than a couple of years old due to wear and dirt. When the LTFT remains higher than 10% or lower than -10%, this can indicate a malfunction in progress, even if a code hasn’t been thrown. As long as a narrow band sensor is oscillating and a wide band sensor is maintaining a steady reading, then the sensors can generally said to be good and the problem is elsewhere, such as a vacuum leak, pirate air entering the intake, a clog in the fuel filter, a clogged air filter, faulty fuel pressure regulator, or a weakening fuel pump. Those aren’t all the reasons, just some of the most common ones. My recommendation is to check out the air flow sensor(s) and make sure there aren’t any leaks or splits in the fresh air intake tubing, and that all the joints are sealed and tight, between the filter box and the throttle body.
This is what a graph of properly operating O2 sensors should look like:
+1. My advice would also be to take it to a shop. You could probably replace the hose yourself, but if you have to hire a shop to do the evac and charge then the additional labor for them to replace the hose is negligible. It is usually cheaper to pay the shop instead of the investment for the DIY to purchase A/C tools as well as a supply of dye, oils, and refrigerants, unless they are experienced and plan to do a fair amount of A/C work. Also note that it is environmentally irresponsible to release refrigerants into the air. (It’s also illegal, but most DIY don’t care about that because they don’t believe they will be caught–and they’re right, they probably won’t, but it still harms the environment nonetheless).
[quote=”ToyotaKarl” post=187531]You say you the valves dont look bent….
Let’s define Bent valves… Bent valves don’t have to look like what some people percieve as bent valves (like pistons crushed them or bent them and They are at a weird angle.
Bent valves very often appear straight but are bent slightly enough to keep the valve from fully seating…
Karl[/quote]
+1. It only takes a few thousandths of an inch.Did you replace the thermostat with the Subaru (OEM) thermo? Subies are very picky with their thermostats. Also, air in the system. Sometimes it can be very tedious to get all the air out, requiring many burpings. If the cooling system checks out fine, the only thing left causing this would be a faulty head gasket.
Check your fuses. Sounds like a blown fuse, or maybe a couple. Check the Maxi 30A fuse under the hood. It’s a cartridge fuse, it looks usually like a little pink plastic box, with a clear top and the number 30 printed on it. This relates to the EEC-IV code 511, no power to PCM pin #1. EEC-IV code 522 and 654 relate to the park/neutral safety switch (522) and transmission not in Park (654). Code 523 relates to the fuel pump circuit. These could all be thrown because the PCM is not working due to a blown fuse.
It’s doubtful although not impossible that the trans you got had the same problem. Is there a warranty on it? Was one of the codes you got P0715? If so, chances are there is a sensor error, most likely input sensor, and the junkyard trans didn’t come with the sensors so your original sensors were re-used which could explain why the problem transferred over to your “new” transmission. If not, what were the exact codes? The PCM may also need to be reset. You can do this with a proper scan tool, or by removing both battery cables from the terminals, wait one minute, touch both cable ends together for 15 seconds to discharge the retention capacitor in the PCM, then reconnect them to battery, positive first, then negative.
“Fussy ignition” is just an expression. Fussy is a word that means something like having a bad temper. So using the word with the ignition illustrates the ignition as having a bad temper. Don’t worry too much about it, it’s just meant to be a somewhat funny phrase and not a technical term. I’m looking forward to finding out what the results of your testing are next week.
Regardless of fractions, the length does absolutely matter, which is why there are different lengths. They wouldn’t go to the effort and expense of making the different ones if it didn’t matter. The tone rings are not sold separately. AutoZone may only carry the non-ABS shafts. You cannot use these if you have ABS. Try Napa instead. Napa has reman’d shafts for about $60 each and will come with the tone rings.
Thanks for the information. You need the following shafts:
Left side: 25-1/2 inch length, 25 spline inner and outer joints, 44 tooth ABS tone ring
Right side: 36-11/16 inch length, 25 spline inner and outer joints, 44 tooth ABS tone ringThere is also a difference if it has ABS brakes. The A/Z catalog doesn’t necessarily have a complete parts list for a given make/model. The shaft lengths are different depending on ABS or not.
The fuel pump on this vehicle, if it is stock, is cam driven and mounted on the block, not in the tank.
The differences in shafts are usually based on several things, specifically type of transmission and brake system. Unfortunately the VIN doesn’t really help much in this case since the VIN doesn’t usually code the transmission and brake types. What is your year, make, model, and is it auto or manual tranmission, and does it have ABS or not?