So, it makes it kind of difficult to identify a part when it goes by 5 different names…
Apparently I took a picture of my “fuel vapor canister”, I think. Shouldn’t there be a way to seal up the rusty parts with some kind of epoxy or something?
EDIT: Damn it, or it something else… It’s metal and round. I can’t figure out what the hell it is…
It must be the vapor canister.
Anyways, this is from another site, but I think it is exactly what is happening, I think there is a blockage because the liquid coming out does not smell like gas, I will investigate further tonight:
"There is a fuel vent problem, the charcoal canister is only supposed to receive fumes from the tank and then send any excess hydrocarbons back to the tank through the vapor return hose, if there is a blockage the canister will saturate with fuel because it will condense rather put the fumes back to the tank, best bet is to have a dealer check it. "
Ok, my vapor canister is very funky. Funky in that is doesn’t look like anyone elses vapor canisters… That is why I’ve had trouble IDing it, here is a good description of it from Chilton:
Obd-II EVAP System Monitor
The 1997-99 models have added system components due to the EVAP system monitor incorporated in the OBD-II engine control system. A pressure sensor is mounted on the fuel tank which measures pressure inside the tank, and a purge flow sensor measures the flow of the gases from the canister into the engine. The purge valve is now called the Vapor Management Valve (VMV). It performs the same functions as the purge valve, however it looks slightly different. A canister vent solenoid is mounted on the canister, taking the place of the vent cap, providing a source of fresh air to the canister.
The PCM can store trouble codes for EVAP system performance, a list of the codes is provided later in this section. Normal testing procedure can be used, see EVAP System Component Testing in this Section.
I’d LIKE to just disconnect the hoses leading to the canister to search for blockage, but they are all metal… And how the disconnect is not obvious. Also, the one metal hose going from the canister to the purge valve at the fire wall has moisture that builds up on it as well.
The moisture on the canister and hoses only appears while I am driving. Once parked, even with the engine left running (and rev’ing it), the moisture quickly evaporates away.
I think you may be looking at the wrong thing. It sounds to me you are looking at something for the AC system, maybe the filter.
You are correct, I just learned that I took a picture of the “accumulator for the a/c system, also called the receiver/drier.” I will do some tests tonight including checking the gas cap, filler neck, etc.
Yeah, the dryer. I couldn’t think of the right name at the time.
I have a hunch that while you were working on the O2 sensors you may have inadvertently caused this other problem. Have you found out what the problem with the O2 heaters is yet? If not, I suggest you get that problem solved first by using the info I gave you earlier. You may also find out what the problem with the fuel system is at the same time. An added note on that, the code says there is a leak in the system so look for a disconnected or fractured hose connection. It could also be a loose fuel cap so retighten it.
This? http://www.partsamerica.com/productdetail.aspx?MfrCode=EVP&MfrPartNumber=3658&PartType=397&PTSet=A
Yes, I will take care of the corrosion with the dryer, but it’s not actually leaking or anything, so I don’t think there is actually a problem there.
First thing I will do is inspect the gas cap and then I’ll follow everyone’s suggestions in the last few posts… to the best I can anyways.
TEST RESULTS:
If your car has the original Bank 2 Oxygen Sensor electrical connector from the car harness, use your voltmeter, with ignition in RUN (engine OFF), to read the voltages on the red/light green wire, the grey/red wire b[/b], and the red wire b[/b].
Now, do Pinpoint Test (DTC P1131) H24 for the signal circuit on Bank 1 front sensor: 1. Disconnect B1S1’s electrical connector. 2. Put a jumper wire into the gray/light blue wire terminal (going to PCM 60), and the other end into the red wire terminal (going to PCM 71). 3. Connect scan tool to car. 4.Turn the ignition key ON, leave the engine OFF. 5.With the scanner, read the B1S1 voltage b[/b]. 6. Turn the ignition key OFF. Results: If the voltage was more than 1 1/2 volts, the wiring is ok (down to the connector). If the voltage is less than 1 1/2 volts, go to Pinpoint Test H25.
Pinpoint test H25: 1.Key OFF. 2. Disconnect PCM []and[/b] B1S1 electrical connectors. 3. Check ohms from PCM 60 to O2 (grey/light blue) plug b[/b]; PCM 91 to O2 (grey/red) plug b[/b]; PCM 93 to O2 (red/white) plug b[/b]; and PCM 71 to O2 (red) plug b[/b]. If this wiring checks ok, then, the problem is inside the O2 sensor. Replacement of the O2 is the only option (this sensor -B1S1- is brand new, just replaced it last weekend)
For P0155 the heater circuit of the Bank 2 front O2 sensor, with the O2 connected, do resistance (ohms) test of PCM 94 (white/black wire) to PCM 71 (red wire) b[/b]. If it checks bad, disconnect B2 front O2 sensor, and check ohms on each wire (PCM 94 (0.7 ohm), and PCM 71 b[/b]to B2S1 plug. Then, ohms check the O2 sensor, red (0.7ohm, but would shoot up to 1.1ohm) and white/black b[/b].
Sorry - Coming into the discussion late, but you asked for thoughts and opinions… The above codes can result from actual out-of-range long-term air/fuel mixture ratio on the air intake side, not a sensor hardware malfunction, not on the exhaust side, and not on the evaporative emissions side. While the engine is breathing a mixture of metered fuel and air, and combusting it, the engine management system takes readings from these sensors, and perhaps the readings are justifiably off the scale. If so, the most common problem at high engine age would be deterioration of hoses on the air intake side (including lines coming from the positive crankcase ventilation system back to the intake manifold), or leaks between the air cleaner and the intake manifold, or a rupture of the pressure control diaphragm inside the PCV oil trap or PCV valve, a broken EGR valve. All of these would result in “unmetered” (unaccounted for) air on the intake side. The engine management system is constantly trying to balance fuel and air. Leaks really screw things up.
When these codes get set, your engine management system should set the Check Engine light and then ignore the out-of range-readings (that doesn’t fix anytthing, although it might smooth out uneven running). With the codes cleared and Check Engine light off, if there really are air leaks on the intake side, you may notice a short period of engine unevenness before the codes set again. If the problems don’t resolve after some number of drive cycles, the Check Engine light will come on again.
With 140k miles, you should check the hoses coming from your PCV valve to your intake manifold, and also the breather hose between the valve cover and the same oil trap, and also check the oil trap pressure control diaphragm. You should check the integrity of the intake path BETWEEN the MAF sensor and the intake manifold because, if the actual mass of air arriving at the intake manifold is greater than the mass that was measured and reported by the MAF sensor, that would of course indicate an unmetered air leak somewhere in between. Long term, you should appropriately set those codes. I could be wrong, but it just sounds like the MAF and O2 sensors are doing their jobs. Rubber hoses have a useful life expectancy, and 140k miles is beyond most useful life predictions. Some plastic hoses are suceptible to degradation upon exposure to alcohol-containing fuels.
DTC P0155: “O2 Heater Circuit (Bank 2, Sensor 1)”.
Diagnostic “Pinpoint Tests” Chart H30 through Hxx.
This DTC P0155 is for the heater circuit of the bank 2, front, oxygen sensor. Your test on the red wire to that O2 sensor shows that the heater isn’t getting the required 12 volts. It could be a bad connection somewhere along the wire. If you check the red wire to another O2 sensor heater, you should see 12 volts. You can trace the red wire back to find the bad part, with voltage (key ON), or ohms checks (key OFF)
DTC P0135: "O2 Heater Circuit (Bank 1, Sensor1).
Diagnostic “Pinpoint Test” H30 through Hxx (Same type test as P0155; but, different wire).
There ISN’T a DTC set for O2 sensor stuck lean, now, is there? If no, don’t worry about O2 sensor Switching.
Jumpering the red wire (12 volts) to the grey/light blue wire of B1S1 oxygen sensor is a test of the PCM. The voltage the PCM sees (1.275 v.) is a little low. Resistance causes voltage to decrease. That may be the reason it’s only 1.275. Will this affect O2 sensor switching? Good question.
You need to see what the voltage is anywhere on the red wire, It should be the same as battery voltage, minus a few tenths volt. You can take voltage readings at the idle air control valve, engine coolant temperature sensor, intake air temperature sensor, etc.
Matthew,
I see you measured the resistance of the heater circuit for sensor 2x1 and it measured almost exactly what I guessed it might be, 10 ohms. You didn’t show any reading for the 1x1 sensor that uses pins 93 and 71 but I now suspect that you will have the same results for it also. Since you have a good resistance for the heater circuit this means the sensor isn’t the trouble. I suspect the PCM isn’t grounding the heater lines for those two sensors and the problem is inside the PCM. To verify that, place your voltmeter probes across the pins I mentioned using pin 71 as the common point to all of them and measure the voltage with the ignition ON. If you have low voltage across the pins the PCM is the problem.
If replacing vacuum hoses took care of the Evap Sys leak (DTC P0455), that only leaves P0135 and P0155 for the front oxygen sensor heater circuits, doesn’t it? It’s either 12 volts isn’t getting to the oxygen sensors (red wire), or in the PCM, or where the PCM grounds those circuits. You’re almost home!
BarryNNJ: No need for apologies, I think you are brave for jumping in to help me this far along in the thread!
BarryNNJ said: “With the codes cleared and Check Engine light off, if there really are air leaks on the intake side, you may notice a short period of engine unevenness before the codes set again. If the problems don’t resolve after some number of drive cycles, the Check Engine light will come on again.”
Great point. I was under the assumption (don’t remember why) that it is NORMAL for the car to drive a little funky after the battery is disconnected for a while. When I say funky I mean that for a couple drives after the battery is disconnected, the rpms jump a little even when cruising on a flat road. So, when driving 65 on a flat, straight highway, the rpms will go from 2k to 2.5k and back down again intermittently (not frequently). I thought this was some normal re-adjustment period.
Almost all of the vacuum hoses have been replaced, along with the PCV valve, fuel pressure regulator, and all of my O2 sensors. And I have cleaned my MAF sensor with a MAF spray.
Hellokit, I will do those tests tonight.
Cougar,
Allow me to make sure that I understand you 100%, do you want me to touch the probe leads to the holes in the wire harness that attaches to the PCM, or the pins actually attached to the PCM (that are exposed once I disconnect the wiring harness)? Either way, you are saying to touch one probe lead to pin 71, and the other to pins the heater lines for the O2 sensors? And what would you consider low, something below 7mv?
Again, thank you everyone. I wish I had a smoke machine.
Alas, it is not so… Codes were reset last night and my current pending codes are P0455, P0135 and P0155.
Googled for a DIY smoke machine… Would this work and be safe?
homemade smoke machine - RX7Club.com - Mazda RX7 Forum
you might be able to make one with a wet/dry vacuum, some dry ice and water, and a home made regulator. 1.) connect the vacuum hose and regulator to the vacuum on the exhaust side. 2.) put the water with the dry in a the vacuum 3.) turn on the vacuum and let the fun begin. you could actually put a restriction on the intake side of the vacuum too.
mfaerber,
The voltage check that Cougar suggests, from pin 71 to pin 93, would reveil if no oxygen heater were getting power. Evidently, the rear oxygen sensors are getting power…no DTCs are being set for their heaters.
I think that the problem is more local to the front oxygen sensors…perhaps, a damaged, or disconnected, red wire.
[i]Cougar,
Allow me to make sure that I understand you 100%, do you want me to touch the probe leads to the holes in the wire harness that attaches to the PCM, or the pins actually attached to the PCM (that are exposed once I disconnect the wiring harness)? Either way, you are saying to touch one probe lead to pin 71, and the other to pins the heater lines for the O2 sensors? And what would you consider low, something below 7mv?[/i]
To check the voltage across the heater lines you will need to measure it with everything connected normally. You may need to use some stick pins to push into the connector pin slot in order to make contact with the pin in the connector and your meter probes. If you do this make sure that any exposed contact doesn’t short to anything. Tape is a good thing to use.
Like I stated in my last post, you have already proved that the entire heater circuit (external of the PCM) for one of the front sensors is ok by measuring the resistance of it from end to end. I assume the other sensor (pins 93 and 71) will show the same thing. You can prove that by removing the connector to the PCM and measure the resistance between those pins on the connector. If that is 10 ohms also then the sensor heater and wiring to it is ok and the only thing left in the circuit that can be bad is inside the PCM itself. End of story.
Matthew, you also asked about pin 71 and the heater voltages. Pin 71 is the common return for all the heaters so yes, one meter probe is placed on it for reference when measuring resistance or voltage for the heaters. The other meter probe is then placed on the other pins, one at a time, to check which ever heater you need to. I assume the voltage that runs the heaters is 12 volts but I am not sure on that. Anything in the millivolt range is insignificant and is basically zero volts in this instance.
One can of worms at once is enough. You need to look at the wiring diagram: Fig. 4 or Fig.5 http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c1528003ad27 There is 12 volt power on the red wire going to PCM pins 71, 97, and lots of things WHENEVER the ignition key is in RUN (ON).
To read supply voltage: Turn the ignition key OFF. Disconnect the PCM electrical connector. Turn ignition key to RUN (ON). Take voltage readings on the wiring harness electrical connector side (NOT on the PCM). Example: Touch red probe of multimeter to pin 71, and black probe of multimeter to ground. Result: 12 volts (hopefully). Move red probe to pin 94 (black probe on ground). Result: lower voltage because of B2S1 heater resistance. Compare voltage values to those on pins 93, 95, 96 (O2 sensor heaters). If there is no voltage, there is a break in the wire, somewhere.
Supply voltage can be checked anywhere on the red voltage supply wire. Pin 71 is chosen because it’s simple. You could go to the PCM Power relay.
SMOKE. You can get canned SMOKE. It would be much simpler than re-inventing the wheel. I don’t think there is a danger of exceeding 1/2 psi with a smoke bomb.
GET these Ford service bulletins about troubleshooting for EVAP leaks, P0455, in particular:
Ford Article No.99-23-4, dated 11/15/1999
Ford Article No.03-20-3 dated 10/13/2003
Ford Article No.97-20-4 dated 09/29/1997
I’ll do the tests.
In regards to the smoke, I wasn’t sure if real smoke machines use some special kind of smoke… So even canned smoke will work… interesting.