Landseer

Did you jumper the three key relays, try to start, and check the control voltage on the exposed sockets?

Richter12x2

I didn't, but I swapped them out for the reverse relay and verified that the reverse lights came on with all three.

Replacing LH relay did nothing. Apparently it needs to be plugged in before it trips the LH relay to send volts to the LH, so I can't just check for voltage on that pin.

The three prong connector by the temp 2 sensor is for the TPS, right? I get full open on all 3 pins with respect to ground when actuating the throttle by hand. Could a dead TPS cause all this? Trying to start with TPS disconnected does nothing.

Landseer

The point is not checking the relays.
Bad relays are often just bad control voltage.

Its bypassing the control voltage, then verifying its level once the car is running, else while trying to start it.

Richter12x2

K, I'll try that as well then. Any idea on whether the TPS would cause issues like that?

Landseer

No, I don't believe so.

Am wondering about voltages, about fuel pressure (see abby normal comment ) and if its just plain flooded. (assuming car has gas of course)

Several of us suffered flooding of S3 cars. Foot to floor, holding there to allow max air through butterfly valve, and constant cranking for 20 second intervals cleared them. They just somtimes suffer from an odd flood-out, generally on a restart or fumbled start.


Also can be classic CPS failure. Or short under MAF or CPS or injector harness boot.

Richter12x2

I'll bypass the relays as you suggested tomorrow after work. I also talked to Roger about the gauge that installs on fuel rail. I'm using Porkens chips, so my guess is that they're a little more picky about fuel pressure than stock chips would be.
It feels and smells like flooding, but could just as easily be clogged fuel filter or something like that. It hasn't run quite right after setting up for about a year.

tveltman

A a pro tip, if the engine floods, you can unplug the LH and leave the EZK plugged in and crank the car. It will fire and burn out the flooded cylinders, then you can hook it up again and she will run fine. I discovered that one by accident, but it seems to work.

Richter12x2

3 key relays would be EZF, LH, and Fuel pump?

edit: Jumpering these had no effect.

Also, tried cranking for over a minute with LH disconnected (not all at once) - no effect.

Car did try to fire while LH was disconnected, so maybe the randomly trying to catch IS due to the cold start injector.

Richter12x2

My fault - evidently it was an anti-flood. Installed one of Roger's trick little fuel pressure gauges and turns out I'm getting no pressure at the rails. I'll replace the fuel filter tomorrow and see what that yields!

Maleficio

Cool.

SeanR

What happens when you jumper the fuel pump relay? If you don't get fuel pressure you either have a bad pump or you ran out of gas.

blown 87

I can say I that I have yet to meet a pro mechanic that has not at some point installed a fuel pump only to find it was out of gas.

SeanR

I spent hours trying to find out why a newly rebuilt CIS car wouldn't run. New pump with 4 gallons dumped in, was trying to set the control pressure and apparently it ran out of gas when I had it right. Could have sworn it had plenty of gas so kept looking other options as to why it would not run.

Not one of my better days.

Richter12x2

I can hear the pump run, so PROBABLY okay. It sat for over a year, so I'm wondering if maybe the filter is clogged.

... but I'll check the gas, too. How bad would it suck if after a month of working on it on and off, tearing it apart several times, that was what it was? My gauges have been known to stick, too.

On the plus side, it should make it a snap to install the new fuel filter. :P

edit: Just double checked, and the gauge SHOWS a little over 1/4, but that doesn't mean the gauge is right. After I change the filter in the morning, I'll pick up a few gallons of Premium to add to it, just to be sure.

Also, my wife reminded me that it was the first thing I checked, because in the state of frustration I was in I MAY OR MAY NOT have said something to the effect of "The gauge says I have plenty, but the filler hole isn't big enough to put my *ahem* in and check it."

Richter12x2

Success! Well, it's not fixed, but it starts, and pretty sure I know what the problem is.

So I jacked up the rear of the car, and was ready to swap out the fuel filter with one I picked up from OReilly, only to determine the one from Oreilly, although it looks the same, the fittings are wrong. But... I figured while I'm down there, I'll go ahead and check the in-tank filter screen and see what's up.

So I popped the rubber hose off the fuel pump and got just a couple of trickles of gas out. I figured "Ah, the gauge WAS wrong, it showed 1/4 tank and I'm obviously out of gas". So I start removing the bolts for the straps so I can get to to the in tank filter. As I'm lowering the tank, I'm still getting little splashes of gas out. So I turn the rubber hose down into my 5 gallon bucket, and I'm getting just a constant weak trickle. After a few minutes of waiting for what was OBVIOUSLY the last little bit of fuel to drain out, I gave up and thought "Maybe if I take off the gas cap, it'll help it come out faster."

Removed the gas cap and it came a flood. I got a 5 gallon bucket full in no time, scrambled under to stick it back on the fuel pump, emptied my bucket into a 5 gallon gas can, replaced it and got 5 MORE gallons out, and no signs of slowing. Obviously that in-tank filter was just fine. I'm out of containers anyway. I hotwired the fuel pump again with the fuel tank off, and no pressure to the rail... turns out powering the fuel pump against a vacuum doesn't do much for it, but after using Sean's trick of reversing the polarity to the pump and bumping it a few times, I got a much healthier whine out of it. Putting polarity back to normal it came right up to 55-ish, where it's supposed to be. Tightened everything down, checked for leaks, and reassembled the top end of the engine where I'd had to go in after the TPS. :P All jumpers out, all relays in, and it starts just like it's supposed to.

So it occurs to me, that about a year and a half ago, when I bought the car, the charcoal cannister was a ratsnest of rotted hoses, so it was removed back then. No issues. But about two months ago, after assembling the new 8" headlights and everything and chasing down coolant leaks, I went back through and removed hoses I didn't need and capped the ends. Must have capped the vent for the fuel tank. :P That also explains why right before it died, that Cobalt kept up with me so well at the redlight... rapidly diminishing fuel pressure probably took about 100 hp off. :P

So now I just have to find a diagram and go find that vent and uncap it. In the meantime, if I need to move the car, I can just leave the fuel cap off, and I should be fine.

Thanks for all the help. I wanted to post the resolution even if it's unlikely anyone will have quite the same issue. :P Also, I have to say, without Roger's fuel rail pressure gauge, I would have been chasing this thing around for several more months, for sure.