Geo Metro: need trouleshooting help please.

[doviatt]

Hi All,

I could use some help troubleshooting an issue with my car that died yesterday on the way home from work.

Car details: '89 Geo Metro 1L 5speed manual 4 door LSI

Problem/Issue: It hesitated and then stalled and would not restart on the way home from work yesterday about a mile away from my house.

Previous directly related symptoms: The last two days during stops on the way home from work- it jerked and lurched when starting out from a stop in 1st gear. Once I got the rpm's up and into second gear and above no hesitation symptoms anymore. This symptom only happened maybe 3-4 times during the last two days which includes 2 stops on the way home to drop off my carpool members. This has never happened before.

Things I've tried:
I originally thought it was me accidentally bumping my kill switch or the kill switch failing or shorting some how during these accelerations. I've ruled this out by engaging the override switch that I installed back when I had installed the kill switch. This override removes the kill button circuit completely because I knew when the momentary button would fail it would fail open (when it wears out). I have also tried re attaching the wires going to the distributor to remove both the kill and override circuits (basically back to original wiring). So manual kill is not part of the problem.
I was initially thinking fuel pump, since history tells me they usually fail slowly and inconsistently and the symptom of hesitation only happened during initial acceleration.

What I have tried (so far):
While cranking (attempting to start):
I looked for spark at the plugs and found none.
I looked for spark out of the coil and found none.
I do measure 12V at the coil input.
I looked for fuel in the TBI throat and saw none.
Sprayed flammable fluid (no starting fluid so tried hairspray :-|) into TBI throat to see if it would catch but, NO.
I listened for fuel pump to buzz when key is put in ACC position. I usually hear the pump kick on but not now.
I made sure the cam is turning while cranking- timing belt checks ok.
Radiator and coolant level are fine.
There is a fuel pump relay but I don't know how to get it out or check it.


What could cause both fuel and spark to go away?



Other recent issues or possibly related or unrelated facts:
I filled up the tank 2 days ago, so yes I have gas and it reads over 1/2 tank full.
I had a catastrophic electrical failure 2 weeks ago when taking it camping. I had not used the lights for a few months and while driving to camping I had the head lights on and ALL electrical shut down (everything went black) when applying brakes (brake lights and had blinker on). Weird. Checked fuses- OK. Removed fuse box screws in engine compartment and moved it around and got the electrical back on. So this means I do have some kind of short or open in my electrical harnesses. Once I put the fuse box back and tightened the screws, though, no more electrical issues and all electrical has been fine for the last two weeks.

Today I'll borrow the Chilton or Haynes manual that the local library has with wiring diagrams. So I'll have things to look at and trace and measure but, I don't know where to start.

Thoughts, ideas, suggestions? Things to check? More info?

Any help is greatly appreciated.

[mavinwy]

I know it sounds silly given that it was hesitating for a couple days before, but have you checked the fuses?

IIRC from my old metro, one is labeled igntion and one fuel pump. But certainly something to check.

Jim

[doviatt]

^^
Not silly at all. The hesitation could have been the warning that it was not capable of keeping up electrically. Thanks Jim good advice.

I'll check all of the fuses first thing after work.
I think the fuel pump is on a relay and not a fuse. Any advice on how to check a relay?

[some_other_dave]

Look for a diagram on the relay body. There will usually be two pins attached to a coil (an electromagnet), and one "input" and one or two "outputs". When no current flows through the electromagnet, the "input" is not connected to anything. When current is flowing through the electromagnet, the input gets connected to the output.

In the case of a relay that has two outputs, one will be connected to the input when there is no current flowing through the electromagnet, and the other will be connected to the input when there is current flowing through the coil of the magnet.

You can run +12V to one "coil" pin and ground to the other, then use an ohmmeter to see if the input is connected to the output. And then remove the +12V and check to see that it isn't connected.

You can also jumper around the relay by connecting the input directly to the output with a piece of wire. Only for testing purposes, please!!

No spark and no fuel sounds a lot like the ECU for the engine management is not getting any power. Can you check to see that the wires that power it have +12V when the key is on? Could also be something failing to tell the engine management that the engine is trying to run.

-soD

[mavinwy]

Mine was a 90, but I have not had it in years (rusted out, sold the motor)

The only other thing I can come up with right offhand if it is not the simple stuff would be cam sensor, but that would not affect the fuel pump. You could check for pressure at the rail, but I'd get spark first.

I don't remember if the fuel pump was a relay or not. They were pretty cheaply made, so it might go either way LOL

But Dave's testing method is right on.

Off to work on the "new" hypermiler.

Jim

[doviatt]

Thanks Jim and Dave,

You guys rock! Great solutions and information.

It did end up being a fuse under the dash labeled IGN. (I'm assuming for ignition?)
The library was closed for a local State holiday so I didn't get the Chilton manual and I don't know what else is in line for this fuse. I'll be checking it out next week.

In the mean time....I'm up and going again, thanks to you guys.

[Phantom]

With turning the lights on and the car hesitating, I would say do your self a favor and check all the grounds. Disconnect the battery and trace all the ground wires check the ring terminals clean off all rust and dirt apply dialectic grease. If you have wiring diagrams this can be easier since you can see where and how your car is grounded.

If there is corrosion and dirt between any of the connections it can create a situation where it can get the electrical signal but the circuit is having to work harder to get it there.

[doviatt]

^^
Great suggestion Phantom. This car has had some serious electrical mysteries in the last couple of years. It's age is showing. Rejuvenating electrical grounds sounds to be a good preventative measure for frustration. I'll get working on that while I'm still sane. ;-)

[mavinwy]

Glad it was an easy fix and you are back mobile...

Jim