95 SSEi Bogged down in low gears NEW UPDATE 3/17
#31
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Originally Posted by BillBoost37
Originally Posted by Mortehl
Yes, I'm going to follow the diagnosis in the FSM for testing the fuel pressure when I get the car back. I didn't realize I wasn't doing it right either.
I need to spend more time RTFM.
I need to spend more time RTFM.
READ BOTH...not just one, it'* a two book series.
after yesterday'* call.
#32
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Update:
I followed the fuel system pressure and the fuel pump actually passed the initial test. I bled the rail and lines, then turned the ignition to on without starting the engine. Fuel presssurized to 41 PSI, which according to the FSM is within spec, though on the low end, but wasn't able to hold the pressure.
I flooded the fuel rail by turning the ignition on and off about 15 times and letting the pump run, but the car fired up properly which according to the book means either a leak in the fuel pump seal or weakening fuel pump. Either way tank needs to drop. Pulling the vac line from the FPR makes the pressure jump to 45 (again within spec) so I know thats functioning properly.
Thanks Boosty for walking me through this and Pat for morale support.
I followed the fuel system pressure and the fuel pump actually passed the initial test. I bled the rail and lines, then turned the ignition to on without starting the engine. Fuel presssurized to 41 PSI, which according to the FSM is within spec, though on the low end, but wasn't able to hold the pressure.
I flooded the fuel rail by turning the ignition on and off about 15 times and letting the pump run, but the car fired up properly which according to the book means either a leak in the fuel pump seal or weakening fuel pump. Either way tank needs to drop. Pulling the vac line from the FPR makes the pressure jump to 45 (again within spec) so I know thats functioning properly.
Thanks Boosty for walking me through this and Pat for morale support.
#33
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How does it run now?
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#34
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Originally Posted by jr's3800
How does it run now?
#35
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Right around the time I cleaned my my car and before I drove it hard enough to notice crappy acceleration, I changed my O2. Tonight while cleaning up my toolcase, I noticed an old O2 sensor and for some reason I couldn't stop staring at it...
Then it hit me: Maybe I bumped on of the spark plugs in the rear and it wasn't getting a good connection anymore with the wire. So I ran downstairs and reseated the boot and fired the car up.. Bang all my missing power was back .
I am a much happier man who'* going to sleep freaking soundly tonight.
Then it hit me: Maybe I bumped on of the spark plugs in the rear and it wasn't getting a good connection anymore with the wire. So I ran downstairs and reseated the boot and fired the car up.. Bang all my missing power was back .
I am a much happier man who'* going to sleep freaking soundly tonight.
#38
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Originally Posted by vital49
I still wouldn't give that pump much longer. 11 years old with all those miles....it'* just a matter of time before it fails.
#39
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Did you pull the boot off to change plug. Seems that I remember that being the easier way.
We should look at this thread and learn a few lessons from it.
1. Conspiracy theories don't stick well if it'* been running well for a week
2. First thing a mechanic asks when you bring a car in with an issue is "Has anything been done lately"
3. We usually cause most of our own problems.
We should look at this thread and learn a few lessons from it.
1. Conspiracy theories don't stick well if it'* been running well for a week
2. First thing a mechanic asks when you bring a car in with an issue is "Has anything been done lately"
3. We usually cause most of our own problems.
#40
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Okay.. I THOUGHT I had the problem licked, but it turns out it was just the cold air.
So.. I've been trying to reason through this myself. Bill and Pat really made me sit down and RTFM. They let me bounce ideas but that was about it. The net result was me figuring out how to use the damn FSMs
So anyway, one of the diagnosis paths lead me to fuel pressure. Yeah my fuel pump is weak, but its just barely within spec. So that was out. I then moved on to ignition. All coils are testing out (we'll ignore certain other funny things I noticed there for another thread.)
Next thing was check the TPS. On the way home from work, I hooked the scantool up and did the one arm WOT runs and noticed I was never getting more than 2 volts on the TPS... WTF? Called up Pat and told him what it was and he said, "That ain't good." So after work, I did a proper diagnosis (Ignition on ON, slowly increase pressure on the pedal) and found that the TPS would get to about 2.8 volts then suddenly tank down to 1 volt. WTF x2? Had fun switching the TPS (I'm sure Bill and Pat will make fun of me here) and the net result is 4 volts at 100% throttle with no dead spots.
I'm not sure if this fixed it as I have to wait for the morning for a test drive, but I'm feeling pretty confident this should be resolving the problem.
So.. I've been trying to reason through this myself. Bill and Pat really made me sit down and RTFM. They let me bounce ideas but that was about it. The net result was me figuring out how to use the damn FSMs
So anyway, one of the diagnosis paths lead me to fuel pressure. Yeah my fuel pump is weak, but its just barely within spec. So that was out. I then moved on to ignition. All coils are testing out (we'll ignore certain other funny things I noticed there for another thread.)
Next thing was check the TPS. On the way home from work, I hooked the scantool up and did the one arm WOT runs and noticed I was never getting more than 2 volts on the TPS... WTF? Called up Pat and told him what it was and he said, "That ain't good." So after work, I did a proper diagnosis (Ignition on ON, slowly increase pressure on the pedal) and found that the TPS would get to about 2.8 volts then suddenly tank down to 1 volt. WTF x2? Had fun switching the TPS (I'm sure Bill and Pat will make fun of me here) and the net result is 4 volts at 100% throttle with no dead spots.
I'm not sure if this fixed it as I have to wait for the morning for a test drive, but I'm feeling pretty confident this should be resolving the problem.