76 bus stalled, ran perfectly and then didn't

[cellobus1]

Hi everyone. I was out in my recently rebuilt 76 bus w/ 2L FI motor. I needed gas, I was at 1/8 tank. I got to the pump, took off the cap and realized I didn't have my wallet. So I put the cap back on, drove about 50 feet (running perfectly) and the thing stalled. I could tell the wheels were making the motor turn, but no go. I coasted to a stop and checked many things. AFM flap, double relay connections, WR-1 connections, starter connections, fuel pump connections, all fine. Removed gas cap in case it was clogged. Vacuum hoses were all tight. S-boot to AAR hose is a little iffy, but like I say, it ran perfectly in spite of that. (I'm going to do the copper elbow fix for it to really eliminate that as a possible problem). Added a couple gallons of gas, no difference, but I could tell it was trying to fire. The AAR seemed hot to the touch, I wasn't sure if that was normal or not.

After I got a tow home, it started, but couldn't stay running.

Could the aux air regulator, fuel pump, thermo-time switch, cold-start valve, or any FI other components just lay down in the middle of a drive?
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1976 unrestored daily driver Standard bus, "Stella"
formerly, 1959 Standard bus
formerly, 1973 transporter which was 4 years old when it taught me to drive

[busdaddy]

It's possible that something failed during the last drive that is now effecting a restart, but that's very uncommon and usually still runs in a crappy way.
The "ran it dry" is the biggest suspect here, good odds you sucked up a floaty in the tank and have a restricted outlet or filter now (hopefully the filter, much easier to access).
A warm AAR is normal, it's electrically heated to act as a timer as it warms and add throttle accordingly, or once the engine compartment is warm stay closed.
If you are confident there's no restrictions in the tank outlet or filter and the pump is delivering more than 1 liter a minute into a bottle with a hose attached to the test port between cylinder 3&4 then start looking for the hidden hose that got blown off when it coughed or backfired while dying.
_________________
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[Wildthings]

Check your ignition points, if you have Bosch points the wear block may have snapped off and thus the points are not opening anywhere near far enough plus your timing is going to be way off. If this is the case buy a set of Echlin points from NAPA and forget running Bosch in the future.

[cellobus1]

I got it towed home and then it started perfectly the next day. I've driven a few times since with no problems, but today, it did it again. I noticed that one of the leads to the resistor block had fallen off, so I rigged that back in in a temporary way. It seems like it would still run without one of the resistor leads attached, though, but just not as well. about a half hour later, after checking all the vacuum hoses and the AAR door multiple times, it started right up and I drove it home, yeah, I guess it could be a floater.
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1976 unrestored daily driver Standard bus, "Stella"
formerly, 1959 Standard bus
formerly, 1973 transporter which was 4 years old when it taught me to drive

[aeromech]

That sounds like one of your injectors wouldn't fire. Better repair that or replace the resistor pack.
_________________
Lead Mechanic: San Diego Air and Space Museum
Licensed Airframe and Powerplant Mechanic
Licensed Pilot (Single engine Land)
Boeing 727,737-200-300-400,757,767
Airbus A319,320,321
DC9/MD80
BAe146
Fokker F28/F100
VW type 1 1962,63,65,69,72
VW Type 2 1971 (3 ea.) 1978, 1969
VW Jetta
VW Passat
Capable of leaping tall buildings in a single bound

[Tcash]

[Cap10323]

I'd use this as a general excuse to go through your fuel system. Doing lines, filter, and cleaning your injectors is an afternoon task.
_________________
-Ian

'77 Westfalia - 2.0 F.I

[cellobus1]

Thanks for the replies, guys. I basically JUST WENT through my fuel system. The injectors are brand new, they had curved hoses on them (which I replaced with straight- btw, they might could be repurposed for the fuel tank vent elbows?) I can't remember the brand. I got them from BusDepot in March.

The gas tank has been capped as long as I've had the car (since 1988). I removed it, shook it, and it made no noise. No dead birds. This is not a problem that I ever had with it for lo these many years.

Anyway, the fuel pump is about three years old. And I'm in the first 300 miles of a rebuild, so there's bound to be something in the filter; after sitting for 9 months, that's when you need a filter the most. It runs perfectly MOST OF THE TIME. Like, brand new perfectly. Arrrgghhh I thought I was done with this.

I know, you're never done with a bus. I'll get out under it tomorrow. For what it's worth, it'll run a little longer before stalling if I've waited a few minutes, even was able to drive a couple feet, but letting the clutch out was basically too much for it.
_________________
1976 unrestored daily driver Standard bus, "Stella"
formerly, 1959 Standard bus
formerly, 1973 transporter which was 4 years old when it taught me to drive

[aeromech]

Get a Bosch noid light. Plug it into each injector connector and check for a light pulse. This will tell you that your injectors are getting an electrical signal. That resistor block has me concerned. I've had to solder them before.
_________________
Lead Mechanic: San Diego Air and Space Museum
Licensed Airframe and Powerplant Mechanic
Licensed Pilot (Single engine Land)
Boeing 727,737-200-300-400,757,767
Airbus A319,320,321
DC9/MD80
BAe146
Fokker F28/F100
VW type 1 1962,63,65,69,72
VW Type 2 1971 (3 ea.) 1978, 1969
VW Jetta
VW Passat
Capable of leaping tall buildings in a single bound

[cellobus1]

Ok, got out under there, took the fuel filter off, and cut it in half. Basically nothing in there, BUT the hose between the pump and the filter was partly clogged. The filter's bigger flange had carved a little flap, a little foreskin out of the inside wall of the hose when it was installed. I didn't know they were so sharp! Plus the hose is pretty ancient, hoping 10mm ID is a common size. I guess I missed one.
_________________
1976 unrestored daily driver Standard bus, "Stella"
formerly, 1959 Standard bus
formerly, 1973 transporter which was 4 years old when it taught me to drive

[cellobus1]

Well I've eliminated yet another problem, but still not the real one. The symptom now seems to be starting up great, idling (or driving) for 3-5 minutes great, no problem, but at some point the idle drops, as if AC was coming on, then shortly just poops out and then (as before) doesn't restart. (It doesn't have AC, but it reminded me of that sensation on other vehicles). Based on extensive perusal of the "Symptoms Solved and Fixed" thread, I suspected the TSII. Lo and behold, it was about 4 turns too loose, which meant perhaps it was making an electrical connection to the head, but the heat was not transferring thoroughly to the sensor. I'll give it a try and see if anything has changed. If nothing changes, I'll try grounding it.

Also please correct me if I'm wrong, but the resistor block case grounds directly to the firewall, yes?
_________________
1976 unrestored daily driver Standard bus, "Stella"
formerly, 1959 Standard bus
formerly, 1973 transporter which was 4 years old when it taught me to drive

[Wildthings]

[Tcash]

[cellobus1]

Yeah, the TSII was the trick! Took about a 15-mile drive and no issues. Thanks for all your suggestions, and thanks Tcash for that thorough compendium of Type 2 maladies.
_________________
1976 unrestored daily driver Standard bus, "Stella"
formerly, 1959 Standard bus
formerly, 1973 transporter which was 4 years old when it taught me to drive

[SGKent]