'85 CRX Si DD won't run longer than 2 seconds, need help on what to test...

[MakDiesel]

Here's the gist:
Mechanically stock daily driven '85 CRX Si with 247k on the clock has run flawless the last 7 years minus a few batteries. Anyway, I'm leaving work at 1am, it's something like 20 degree F outside and she cranks, physically runs for a couple seconds, then dies out. Rinse, repeat, disappoint. Here's what I've narrowed it down to:

1. everything in the dash lights like normal on ignition II (Run), no CEL/MIL
2. she cranks like normal and fires/runs for approx. 2-3 seconds, then dies as if there is no fuel and/or spark.
3. I can hear the pump kick on when I turn to IGN II (for the 2 second prime)
4. I do NOT hear the pump after the car cranks, runs, & key is back to IGN II
5. Fusible links, regular underdash fuses, have been checked and are good
6. I naturally smell fuel after a few attempts of her running off the 2 second prime

My guess was the main relay had failed, I have removed it and tested it per HELMS & it checks out ok, altho I noticed a few faint hairline cracks in a few joints & resoldered every single one to be on the safe side. I tried out the re-soldered one and got the same result. I'll have to wait til after work to test the harness. Kinda sucks doing all this in the parking lot at 1am in 20 degree weather...

I also have a spare ECU to test, altho ECU failure is extremely rare in a Honda. My only other guess is a inner-distributor issue, like the ignitor, although I figured she wouldn't fire at all if that was the case & I have no way of checking. Any thoughts? Thanks in advance, Mak

Left to test:
- harness
- ECU
- distributor
- fuel pressure regulator?

Keep in mind I'm in a parking lot. At night. And it's coooold.

[GasSavers_Erik]

Check for spark first-

1. turn the key to the "run" position, put it in neutral,
2. slide the harness connector off the start terminal on the starter and use a jumper wire to give that terminal 12 volts (from the positive terminal of the battery or from the 12v terminal on the starter).
3. Now you can pull a plug wire off and check for spark with one hand, while you give the start terminal 12 volts with the other hand.

[GasSavers_Erik]

If no spark in the run position:

1. it could be a bad ignition switch "run" contact- maybe you could check to see if the coil and dizzy are getting 12 volts. If they aren't then maybe you could temporarily give them 12v via a jumper wire from the battery.

If you don't have time for this/can't track down the wires and have a buddy with you, have the buddy start the car and continue holding the key in the "start" position while you are holding the start wire connector on the starter. Pull the connector off the terminal on the starter as soon as it starts in order to avoid damaging the starter drive and getting that horrid grinding noise. If it runs OK in the start position, then maybe you could check out a wiring diagram and "hotwire" it to get yourself home.

2. bad igniter or dizzy?- in which case you will have just to replace it - but I don't see why it would fire OK when cranking

If spark is OK in the "run" position, then it has to be a fuel issue.

1. Bad main relay (even if it checked OK and you re-soldered it)- Maybe you can bypass the main relay by running a wire from a headlight fuse terminal in the fuse box, to the fuel pump fuse terminal in the fuse box.

2. Bad fuel pump- it would likely be making funny noises when priming or wouldn't prime at all

3. severely clogged fuel filter?- enough gets through to start it, but not enough to keep it running

4. Fuel pressure regulator- you can pull the vacuum hose off and check for gas in the vac hose (in the event the diaphragm was busted).



Based in the info in the original post- I predict that it is a bad "run" contact in the ignition switch

[MakDiesel]

After an hour and a half in 23 degree weather 2:30 a.m., she finally fired and stayed that way. I tested the voltage of the relay harness, swapped relays for fun, checked for fuel in the fuel pressure regulator vacuum hose (smelled like gas to me, I'm guessing from the dozen of so cranks without burning out all the rich start mix?), even checked the ignition switch contacts with a MM (they were good...which will confuse me later on) and was about to call it quits for the night when I finally got the switch itself off and found this: (check 3' o clock for the culprit)


I scrubbed the contacts with a little 220 sandpaper I had in the glovebox and she fired right up! I played around with the IGN II pressure/position and indeed she died like before depending on how the key was positioned. Thanks Erik for helping out, I do appreciate it, Mak

[VetteOwner]

sounds like my s10, would stumble around and cut out if it was idiling. could jiggle the keys and make it stall haha

[MakDiesel]

I WAS WRONG! Installed the new switch, fired fine. Drove to work today, got 5 miles out and the car died, no fuel. Sitting on the side of the highway I try, repeatedly, to get her to run and failed. I swapped the new ignition for the freshly sanded contacts old one and still nothing.

- She will turn over.
- All dash lights work as normal.
- Starter is fine.
- Relay clicks, then clicks again on IGN II (Run).
- NO FUEL PUMP NOISE WHATSOEVER. Not even the 2 sec. prime. This a new symptom vs. last week.

My new guess is either the pump is going, going, gone or the wiring between the ignition switch and the relay is suspect. I'm officially frustrated, Mak

[theholycow]

Could you eliminate the fuel pump wiring as a cause by wiring in your own switch and harness?

[GasSavers_Erik]

Originally Posted by theholycow

Could you eliminate the fuel pump wiring as a cause by wiring in your own switch and harness?

I second that idea

[benfrogg]

Those relays can fail and still click. There should be three clicks total; the two you are hearing, then a click 2 seconds after the second click. (while at IGN II)

1. If you aren't hearing the pump prime but are hearing the third click, it is the pump or wiring to the pump. (grounds, etc)
2. If, OTOH, you aren't hearing the pump prime AND you are NOT hearing the third click, it is the relay for sure. It is more rare to fail this way, but it does happen.

My relay wasn't failing at all until after I started EOC a lot. It seemed to have exacerbated the problem. I put the relay through a lot more cycles with my kill switch.
Your ignition was faulty either way. It's likely it was the cause of the demise of the fuel pump or main relay as such. Like my EOC put more stress on my main relay, so too did your ignition put extra stress on the related bits.
Additionally, these problems could have been co-occurring. That makes it an even harder to find gremlin.

I'd try swapping in your spare relay when this happens.
You can also test voltage at the harness for the fuel tank when this happens. (per helms manual) Although, that would require pulling the seat and such.

At least you've narrowed it down! It can't be the ignition switch anymore.
B

[MakDiesel]

Got the car towed at 2 a.m. after messing with it after work for an hour. I had HELMS handy and tested the relay harness itself, after the test of jumping the fuel pump directly with a known 12v source, I heard nothing = fuel pump wiring is bad, more likely the fuel pump itself. I've got a day off coming up, I'll test for voltage at the pump plug, then I'll have my answer...btw, I went tested the relay completely via HELMS, it checked out fine but I resoldered and re-tested to be super sure (my '89 HF-Z1 died randomly due to a bad relay last summer so I wasn't going that route again.) I'll let you know what I find. Mak