Why am I stuck on the side of the road?
 

Tried to drive the Miata in to work today, and it suddenly died. AFRs went full lean, then it died. I was logging at the time, so I can post any log data.

https://cimg3.ibsrv.net/gimg/www.mia...0cbb0ab01d.jpg

Did it start back up after it died? Anything else you noticed that might have been out of the usual?

Fuel pumps don't last forever. That was my issue last month. Other items to check, main relay, fuel pump relay, frayed wiring.

Are you still stuck on the side of the road? If you are in the kent area I might be able to leave work for a bit and help.

No nothing obvious. It doesn't seem to be a lost sinc, since the count was 0 until after the afr went full lean.

This sounds stupid, but it might be just it of gas? It didn't sputter though. My empty mark might have moved after changing my gauge faces. I have a friend bringing me some gas

I'm in Snohomish, but thanks.

I hear the pump priming when I turn the ignition on.

Aaaaaand it was gas. I ran out of gas. Like a dope. 1/8th tank is the new empty.

Heh. I know someone who brought his new race car to the track for a test day, took it out, spent an hour debugging "misfires", gave up, towed it home, dropped it off at his mechanic's, and then paid for 3 hours of labor to diagnose a car that was out of gas and had a broken gas gauge. :)

--Ian

Oh man, I hope you gave him a hard time for that one. I feel lucky I was logging. I would have checked a bunch of other things first otherwise. Seeing the AFR go max lean in the log before any other events combined with a pump that was still priming was a strong indicator.

I cam fairly close to doing this in my NB. My NA only takes 9.5 galons when the pointer has gone past the empty line and is pointing at the top left corner of the E. The NB is out at the line... I was just a smidge above it when I filled up the first time and took almost a whole tank of gas...

Random question slightly relates to the comment.

Why do you guys let your tanks get so low? I killed a DW400 on my supercharger Mustang a long time ago, and I suspect it was because I always ran the tank to almost empty before refilling.

Because of reasons mostly.

because i have to idle for 30 minutes at costco before the pump is available to save .05 a gallon.

Isnt this the truth though.

Because the Miata has a tiny tank and mediocre fuel economy? This was the reason I drove my S2000 up to 50 miles with the gas light on regularly. Otherwise I would have been filling up everyday.

Because fuel is heavy, dude. :)

(Actually a semi-serious answer here -- most serious autocrossers will run with just enough fuel to keep it from starving in corners, because that's 60 pounds of weight they don't need to carry around the course).

--Ian

Many brain cells were lost in the reading of this thread

Many lost brain cells contributed to the creation of this thread.

Lololol

Hold on. I'm not done.
Lololol

Yeah, that's about how I feel about the whole situation.

I can get 300 miles on a tank, even doing 75mph with the AC on. But yea it does get pretty crappy range, especially compared to my insight where I get 600 miles on the same amount of fuel.

That I get, but on the street. Meh.

Ha HA,,,shite......never mind....I'm pleasantly surprised how lighty you got off here....but lets face it we've all fucked up. wether it was empty gas tank or something else
great thing it was only lack of petrol in your case.

Well, the plot thickens. It just happened again with a full tank. Must be a fuel pump on the way out.

Yep. Easy job.

I was like you and looked elsewhere first. I didn't think fuel pumps could be intermittent. But, apparently, electric fuel pumps behave this way when they are at end of life. Driving along all happy and then . . . nothing! Let it sit a few minutes and it fires back up.

Just ordered up a DW200. Hopefully that'll be the end of this sordid tale.

Dang it! Car stopped again.

It gave me a clue this time though. When it was happening, the fuel pump wouldn't run but the cooling fan was being lightly back-driven. Checked the wiring diagrams and . . . bad ground . . . duh! Check/clean your grounds. The one that is under the brake booster/clutch master is especially important. Both your fuel pump relay and your cooling fan ground there. That area also gets soaked if you wash your engine bay or if a heater hose develops a leak. Turbos cook the area.

Basics.

Good put. I'll give it a scrub.

Anyone with experience putting in the DW200 in a 90-93? The kit comes with 3 o-rings, but I could only get 2 to fit on the fuel out nipple with the lower spacer in place. Also this o-ring retainer thing snapped when I tried to force it on. Anyone know if it is intended to swap over? Is it critical? Any way to get a hold of extra one?

https://cimg5.ibsrv.net/gimg/www.mia...11e7383ba1.jpg

I replaced mine with an OEM Denso pump. It came with a new retainer. The only problem I see with a cracked retainer is that the O-ring won't seal. If you let the fuel get really low, you might suck a bit of air rather than drawing 100% from the sock.

I'm trending towards thinking I don't need it. The DW pump nipple has a cast in ridge to retain the o rings, which is why the old retainer split when I tried to force it on.

Definitely use the ridge if it has one.

ugh... car no start.

so I just swapped in the DW200 fuel pump. I'm cranking, and getting no start. Tail pipe sniff suggests it's getting lots of fuel. While logging my non-start cranks, I'm noticing that the battery voltage in TS looks really low. I'm showing 12.8-12.5v when I measure across the posts of 2 different batteries I've tried, but 11.7v in TS. I've never needed to use the "calibrate battery voltage" tool in TS, and the manual basically says: "don't fiddle with it". Some googling turns up a few posts where Brain & others recommend checking voltage at the injectors. What is the calibration procedure? TS wants the supply voltage at min and max ADC count. Can this be done without a running vehicle? Also, is this just a band aid? should I be chasing a grounding issue instead?

Measured voltage at injectors with just the key in the on position, and I was seeing 12.2v. I just fiddled with the calibration setting until the battery v gauge in TS matched. Damn thing fired right up.

Hmm... Still happening. Getting much worse. I could only idle it for a few minutes before it stalls. Cracked open the pump relay, and it looks like too much of the smoke has got out of the wires. Hopefully this is just a tired old relay problem...

https://cimg7.ibsrv.net/gimg/www.mia...811cf64a33.jpg
https://cimg8.ibsrv.net/gimg/www.mia...b847a73bbc.jpg
https://cimg9.ibsrv.net/gimg/www.mia...8859cd7c89.jpg

Use a jumper wire to test for free.