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Today I unplugged the temp sensor and it started up and ran really rough for just a few seconds, then back to the usual nothing. I haven't been able to get a replacement sensor yet, so I pulled the suspect one out and experimented with it. It checked out according to the Haynes manual tests, so it would seem to me that even though it could still be bad, it's giving a signal at least pretty close to what the ECM would expect. so it seems to me that it shouldn't completely disable the car if it's just off a little. I then found a matching bolt to plug the sensor hole and experimented with heating up the sensor and cooling it down manually while trying to start it and it had no effect. I then checked the OBD codes and the 21 & 13 (knock and cam angle sensors) cleared, and the 22 (temp sensor) showed up since it did sort of start while it was unplugged. So I still don't understand why those 21 & 13 were still in there yesterday, but I guess since it ran a little and enough to trigger 22 and only 22, before it died, it seems that the ECM isn't recognizing any other problems.

Anyway, that was about the extent of my testing today since I spent most of the time trying to push it out of my lawn and into my driveway/garage, but we have had so much rain, that it just sinks into the soft ground every time you stop rolling it and I have some obstacles to move it around. Fun stuff.

Replacing the plug wires helped. I decided to check for spark since I had someone handy to turn the key and I found out the hard way that there was plenty of spark right through my leather glove and the wire shielding. Went straight to NAPA and got a new wire set. Put it in and the car started for a little bit, then died, so I unplugged the temp sensor and it started again for a little bit and died. Rinsed and repeated a couple times, so I think it was flooding then going lean, etc. Took a shower, went back out fired it up, drove it out of my yard and into my driveway (finally), them let it warm to operating temp, then ran it up and down my driveway a couple times, then up and down the road and it seemed to be running fine. Let it run idle for another ten minutes or so while I put things back together and it ran fine. No check engine light. I then shut it down and tried to fire it back up and it really has a hard time starting now, but it will, so I'm thinking that this is indeed indicating a problem with the temp sensor. I'll probably hit the dealer and replace that tomorrow.

temp sensor.....go buy now!

I have to wait until lunch.

Damn. They don't have it in stock. Will be here Wednesday. $26 with my dealer hookup. You know Autozone carries that part? That surprised me. $40.

Dave

Ok, I replaced the coolant temp sensor and it's still dead. Acts sorta like it wants to start every dozen cranks or so, but nope. Still seems like a cold start issue. Like if I got it to start, it would run fine like it did the other day. Doesn't make sense. I still think it's flooding. Any other ideas?

Thanks

Yeah, that thing is flooding. Wreaks of gas. WTF? Sticky injector? Don't even want to think about testing injectors. That's never fun. I guess I'll let her dry out again and try some more cranking tomorrow. Ready to start the bidding on that car. Never had a problem before and now, I'm lost.

Dave

cam or crank sensors. You checked and it had spark right?

Did you reset the ECU?

Yeah, the battery has been out of the car and charging on my workbench overnight a couple times during this process, so the ECU has been reset. And it has spark too. Shocked me right through the wire insulator and glove. That's why I replaced the wires Sunday. Then it ran fine after that... until I tried to start it again. Now back to square 1. I guess I could check for codes again, but I think the only thing I'll see is the temp sensor since I had expiremented with unplugging it. The cam or crank sensors wouldn't have intermittent problems would they? I guess anything's possible. The only thing I can do is check for resistance on those, so I doubt that will tell me much.

Thanks,

Dave

I was just noodling over this... doesn't the cam or crank sensor, or both, control the spark timing as well as the fuel? I was just thinking that maybe I could eliminate one or both of those as the culprit since I know I have a spark.

Thanks

Anyone know the voltage that the fuel pump should be getting off the top of their head? I'm getting a constant 4.74v and I'm pretty certain now that there is no activity from the pump.

Thanks

It should be getting full battery voltage. Sounds like your wiring needs some TLC... You can try just jumpering the pump to a good +12v source and seeing if ithe car starts. If it works, you should rewire the pump.

Ok, I thought that was too low too. If we're sure it's 12v, I'll hook a 12v battery to it and see what happens. In case y'all never hear from me again, I blew myself up.

Anyone know which relay is for the fuel pump? There's three up under the dash that I have found so far, one is for the fans and they're all identical. I've played musical relays a little, what should have been enough to eliminate the relay as the cause, but knowing what the third one is and which one is for the pump would help. Also knowing if there is actually a fuse for the pump would help too, especially if I have to rewire the pump. I haven't found one. I think that must apply only to second generation Legacies. If I didn't have a second gen car, I would trash that book.

Thanks

Be really careful - sparks near fuel vapors are dangerous.

The fuel pump relay is way up high under the dash, not directly above the fuse box. It is a cylindrical silver-colored relay mounted next to the brown box-shaped ignition relay. I think it might be of the same construction as the fan relay.

You might be better off running a new power wire to the pump, though, and using the stock wiring to power a new relay to switch it.

There is no fuse for the pump alone.

This is for a 92 and what you're referring to sounds more like the pictures in the Haynes manual that show different colored, different shape relays and on mine there appear to be only three tall, then, rectangular black plastic relays, one of which is for the cooling fans, one, I'm assuming, is for the fuel pump and I'm not sure about the other. If you are referring to a gen 1 setup, I must be looking in the wrong place although it is in the same location that you describe (above the fuse box). I would like to at least track down the relay before running new wire.

Btw, hooking a battery up to the fuel pump worked like a charm in a dream I had last night. Heh. I have been working on this too long.

Thanks

Hehehe... I've definitely had those "successful diagnosis and repair" dreams too.

I meant that the fuel pump relay and ignition relay are mounted way high up, not with the fan relay above the fuse box. I think they're actually mounted on the inner side of the firewall. You can barely see them if you remove the trim and aim a flashlight up high. Do a search on "ignition relay" to see where I might have discussed how to reach them back when I remembered doing the job better.

Ok, that helps. I'll see if I can find your earlier post, then look around some more.

Yeah, I was disappointed when I woke up this morning and my car wasn't fixed.

Thanks

Perhaps I'm not measuring the fuel pump voltage after all after reading this thread:
http://bbs.legacycentral.org/viewtopic. ... tion+relay

I lifted up the carpet pretty far a couple times and never saw the oval fuel pump cover on the passenger side. I just figured it was another discrepency in the book, right after the part where it instructed me to remove the seat to access the pump. I thought that maybe the low voltage was an indication of it being a sender unit, but since there was a fuel line coming from the same cover and I didn't see the oval cover, it had to be the pump. I guess I'll take another look.

I never really did find much on the fuel pump relay.

Thanks

Underneath the oval cover on the passenger side you will find both a level sender and the pump.

I describe the location of the relay in this thread:
http://bbs.legacycentral.org/viewtopic.php?p=4451

Ok, I didn't see that one. Thanks. So the seat bottom DOES need to come off to access the oval cover? That would explain why I couldn't find it.

Thanks

Hm. I guess so.

I thought that I originally thought it was under the seat and then I found I was wrong and it was under the trunk carpet.

I found another thread on here and it kind of looks like it could be in either place. I'll triple check the trunk and if I don't find it there, I'll check under the seat. It's gotta be hiding somewhere!

Thanks

BTW, the fuel pump relay is up in the dash on the driver's side near the vent. It has a green connector

So where are you measuring voltage for the fuel pump....at the connector under the seat?

Yeah both access panels for the pump are in the trunk.

I think I found the problem. I pulled the seat bottom off last night and saw the wire harnesses and no oval cover, but noticed that the wire harness connector to the pump was a little burned up (I saw this same thing on a thread yesterday), so I pulled it to check it out and got 12v at one of the leads, but not the burnt one. I think I tested and verified it was a ground. So I played with it a little, then connected it back up and checked continuity through each side of the burnt lead and it was connecting, so I moved on to the trunk in search of the oval fuel pump cover. Found it by folding the seat down on that side. Pulled the plug and got 12v on one of the leads. Then I looked at the fuel pump side of the plug and noticed that it had a little dirt or corrosion on a couple of the contacts, so I cleaned that the best I could with a q-tip and electronic parts cleaner. Plugged it back in and the car fired right up. Several times. Then, while it was running, I felt the wire that showed signs of burning and it was fairly hot. Something isn't right there. Why would that wire, which seems to be a negative, be hot?? Like I said earlier, I saw this on a thread somewhere on this board while searching around yesterday and whoever posted it, bypassed a couple of of the leads on that harness connector by using new terminators. I'll try to find that thread again when I have time, but I don't think it ever explained why those wires were burning up. Any ideas on this one?

Thanks

PS- I took an '05 Legacy GT Turbo limited 5-speed on an overnight test drive and flogged the piss out of it. Fun car. Fast. We picked it apart pretty hard last night and still don't think it has the gen 1 quality, but much better than the generations in betweeen. Not sure if I'll get one. Lots of $$$.

Cool, so you identified the problem!

The wire's hot because it's coming apart internally so its resistance is high. If you measure the voltage across the terminals of the pump while it's running, you'll find it noticeably lower than battery voltage. It's not longer up to the task of carrying the fuel pump's current.

Replacing the connector will be fine if this poor conductivity problem is only happening in the connector and not in the wire.

But I'd say the best thing to do would be to run a new power wire and have the existing circuitry operate a relay.