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Discussion Starter · #1 ·
Hey Eurovan Lovers:wave:

I've got an August '92 production automatic trans Eurovan GL that will die, either just going down the road or sitting in traffic. It shuts off abruptly, like someone's turned off the key. It restarts immediately.

It usually won't stay "broke down" long enough to do much of any testing, but on 2 occations, I've found no spark from the coil, eventhough position 15 on the coil pack was getting 12v. I replaced the coil with a new unit, but the problem continues.

Based on some reading online tonight, it looks like relay #30 in position #3 powers the ECU/ECM and could have a broken solder joint. I'll replace it with a spare one that I probably have, and inspect the original one for a failed solder joint. I had a spare fuel pump relay and popped that in tonight, but haven't driven on it yet.

I was thinking that it could be the ignition switch, but the one time I was able to get a meter on position 15, I had battery voltage during cranking.

Any advice would be greatly appreciated.
 

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Discussion Starter · #2 ·
With the ECU power supply relay, and the fuel pump relay replaced with used versions, it fired up this morning, ran an errand, and then let it sit and run in the driveway with the A/C running and headlights on for 3hrs. Ran perfect.

Jumped in it and started running local errands, again, perfect running and no problem on hot-soak restarts.

At about hour #4 of running, including a 26mi round trip on the highway, it simply shut off while waiting at a traffic light. It was an instant shut down, just like someone had turned the key off. It immediately fired right back up on the first attempt, with little more than a blip of the key.:banghead:

Since I don't know the true condition of the 2 relays, I'm going to order new replacements before I start on a wild goose chase.

Anyone have some info to add?
 

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I don't have a solution but I'll share a similar experience.

I have a '93 manual-transmission one that dies mostly because it fails to maintain idle. Sometimes the RPMs dip below idle and recover, other times no recovery and stumbles to a stall, other times stalls very fast (RPMs drop very fast as if key turned off).

The pattern(s):

1. More likely to stall when cold-ish vs. hot (but if A/C is on the added load is likely to kill it hot while when hot and no A/C it rarely stalls).

2. More likely for RPMs to dip but recover or dip and stall when I have been coasting in gear with throttle closed (e.g.: going down a long hill w/o touching the gas or decelerating for a while w/o touching gas).

3. If I leave my house cold and go uphill, not likely to stall at the next few stop signs. If I leave my house cold and go downhill (so a lot of closed-throttle coasting in gear), very likely to stall at the new few stop signs.

4. Almost guaranteed to NOT stall if I am using the throttle and then push in clutch (e.g.: there was a demand for fuel).

5. Can pop clutch to start it up again, but if you push in clutch again it is very likely to stall again.

6. Can use key to restart it and it will start and idle no problem 100% of the time.

The last part is the kicker. Restarting with the key I believe causes the cold-start injector to spritz some extra fuel in (because it will start up and go to about 1100rpm for a few seconds and then settle to its usual 800 or so, telling me it had some extra fuel).

So my theory is that it's a fuel delivery problem. Something on deceleration is cutting the fuel supply (probably normal with most FI engines) and fuel pressure probably drops over time, but if the clutch is pushed in it will not have the minimum fuel to idle and so it stalls.

In addition I noticed a few times (but not all the time) on popping the clutch, the (aftermarket) radio itself cut off and turned off again when the car restarted. This really confuses me, as that it indicates an electrical issue (although not necessarily ignition...could be electrical-but-fuel such as the fuel pump relay or something else shorting out). And the radio cutting out isn't a radio problem...I recall this starting/stalling issue with the factory radio in place too so I'm not calling the radio a cause but more of a symptom.

So my suspicion is a fuel pump relay or maybe even the ECM relay where something shuts down when fuel isn't needed much and it fails to fire up again when fuel is needed to idle.

And while all this is happening, like if I've been decelerating in gear a while such that I know it would stall if the clutch is pushed in, if I just gas it the car accelerates fine, so I think it is responding to an open throttle OK but just failing to idle with a closed throttle. Hence I am focusing on fuel delivery and something electrical not turning it back on.

I have replaced all the little vacuum hoses under the hood and still the issue persists so unless it's one of the larger hoses, etc., that's not it. Also, when it does idle, it idles beautifully and steady and correctly...a vaccuum leak would more likely cause erratic idle.

So, no solution but that's my hunch (control of fuel delivery). I just haven't bothered to solve it yet. Oh any my coil is pretty new too (less than 2 years old) so I'm ruling that out.
 

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Discussion Starter · #4 ·
We interrupt this program to bring you the following

If I was working on your van, I'd do an induction service with the 3 pack BG44K kit (ebay is your cheapest source) and clean the ISV/ICV at the same time. I'd follow that up with a drive somewhere hilly, where I could run the throttle at, or close to, wide open, with some hill climbing load (note that I'm not saying that I'd be running down the road at 100mph, nor am I saying I'd be holding the engine at 5,000rpm), say, 3rd or 4th gear at about 30-50mph, in order to really open the injectors and get some cleaner through them.

I'd follow this service and susequent tank of fuel containing one of the cans of BG products, with a tank of fuel containing a can of Seafoam.

On a side note, if you're running anything other factory OEM ignition parts, including those cheap Bosch Platinum plugs, you're going to have driveability issues.

A comment about the vacuum lines. There is a long 3mm cloth braided vacuum line that runs from the T near the fuel pressure regulator, over to the ECU/ECM, where it plugs into a fitting on the ECU/ECM. Make sure you replace this line. You may also want to check for the ability to hold vacuum, because there is probably a short piece of rubber hose inside the ECU/ECM that spans from the fitting, to the manifold pressure sensor. Real common for this short hose to fail on the TDi's that use the same set up.

Now back to our regularly scheduled program:thumbup:
 

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On a side note, if you're running anything other factory OEM ignition parts, including those cheap Bosch Platinum plugs, you're going to have driveability issues.
Nobody likes those plugs yet they've been around for at least 25 years. I wonder why they still make them?

I actually am running them now (the shop that replaced my plugs put them in...I wouldn't have chose them myself). Although IIRC I did have this stalling problem before those plugs went in (although my memory might be fuzzy).

You may also want to check for the ability to hold vacuum, because there is probably a short piece of rubber hose inside the ECU/ECM that spans from the fitting, to the manifold pressure sensor. Real common for this short hose to fail on the TDi's that use the same set up.
Hmmm...I have replaced the long line but not the internal one (if it exists). How hard is it to open the ECM?
 

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Discussion Starter · #6 ·
First step, get those Bosch Platinums to a trash can where they belong. Even when I was in Bosch Fuel Injection Training School back in the early 90's, the Bosch Instructors were telling us not to put them in anything unless we wanted to start chasing driveability issues.

Just put in a nice set of NGK's and you'll never have a problem.

When we picked this van up, it had a new set of Denso's, but all the other parts were OEM Bosch. When I finished the engine work, I left the Denso's in, because they were "new" with maybe a couple thousand on them. They went 10,000mi before they failed. They started leaking compression around the base where the porcelain center seals against the metal "nut." The van ran so bad, I seriously thought it had either eaten a piston or burned the valves......so I started my diagnostics with a compression test. I never start diagnostics with a compression test, if that gives you any idea of how bad this thing ran. Well, in taking out the plugs I noticed this weird burn stain on the porcelain....D'oh.

New set of NGK's and it was fixed.

The end of the ECU is screwed to the ECU's "box" with a few torx bit screws. Then the end with circuit board attached, will just slide out of the box. If it's got a hose inside, you'll see it right there, running from the fitting in the end, an inch or 2 straight in to the pressure sensor.

Got a report on Saturday that the Van had been running fine and hadn't shut down on them, so I guess the relay's fixed it. The new relays will be here this morning and I'll pop them in......and hopefully that will close the case.
 

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I own a 1992 gas auto Eurovan and was experiencing the exact same problem, occational shut off at idle as if someone turned off the key.

Finally the thing died while driving and wouldn't restart. Turned out to be the fuel pump.
Changed the filter first but didn't fix anything. Ripped out the in tank pump and replaced, started right away. No stalling issues since.
 

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Discussion Starter · #8 ·
Thanks for weighing in. I was initially thinking fuel pump too, but it was shutting off so instantaneously, that steered toward the ignition side of things.

As it stands right now, the van has been trouble free since I replaced the fuel pump and power supply relays. He's says it's died a couple times immediately following a cold start, but restarts instantly and has had no other issues.
 

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Discussion Starter · #10 ·
Wouldn't hurt to carry a spare of each since the pair is under $20. There's another relay that sits on top of the main board, about 1 or 2 in from the right (as you face the board) that gets super hot during running. That's another on my list to replace. I've been too lazy to crack open the Bentley and see what it does.:cool:
 

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Discussion Starter · #11 ·
Thought I'd provide an update.

The problem is still not cured. It's still so intermittent that it's nearly impossible to duplicate, and if/when it does shut down, it almost always restarts instantly. On one occation a few weeks ago, it died on them in traffic and wouldn't restart for a couple minutes worth of attempts, then fired up, ran fine and has been fine since.

I'm almost ready to put a computer in it, and would, if I had a spare. They're $200+ on ebay though, so I'm not ready to spend that on a guess.
 

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Discussion Starter · #13 ·
Yeah, I put in a good used distributor and it did the exact same thing. That was one of the first things I swapped out.

Thanks for the suggestion though.:thumbup:
 

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Wow, lots of creative guesses, but how about an actual scan to check for DTCs?

I had a 93 Eurovan with an idle problem, and the culprit was the 'idle regulator' (or something to that effect...), which happened to be a very specific part, ~ $200 repair, IIRC?
 

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Discussion Starter · #15 ·
Oh sure, now you want me to act like a real tech:rolleyes:

Looks like it's finally gotten worse to the point it'll barely run. It'll be showing up on a hook, sometime tomorrow. Maybe I'll finally get to the bottom of this.

The current condition is that it'll start and run, but the engine has to be kept above 2,000rpm or it just dies.

Can hardly wait....:sly:
 

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Oh sure, now you want me to act like a real tech:rolleyes:

Looks like it's finally gotten worse to the point it'll barely run. It'll be showing up on a hook, sometime tomorrow. Maybe I'll finally get to the bottom of this.

The current condition is that it'll start and run, but the engine has to be kept above 2,000rpm or it just dies.

Can hardly wait....:sly:
In the future, you could probably find another forum user with a VAG-COM cable to do a scan for you, and at least see if you have obvious DTCs with known causes/solutions via the forums @ ross-tech.com.

I have a VAG-COM cable, and would be happy to help you with a ($FREE) scan, but it looks like you're in Central CA, and I'm in SoCal, in the Inland Empire.
 

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Discussion Starter · #17 ·
I actually have VAG-COM, but as yet haven't scanned for codes because the CEL isn't illuminated. I will scan it today though......and report back.
 

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Discussion Starter · #18 ·
No engine ECU codes.

Transmission ECU is showing
- 00529 Engine Speed Signal Missing
35-10 Intermittent

-00545 Engine-Transmission Electric Connection
31-10 Open or short to ground Intermittent


But wait, what's that clinking noise from the new Bosal exhaust system and new cat, all of which have 9,000mi on them. Oh.....just the f-ing cat has grenaded and sent itself downstream into the middle muffler.:mad:

And more....right now it goes from running fine, to a super lean condition with popping in the intake, and won't start without a bunch of throttle, and then runs like the air boot has a giant hole in it. Then might go right back to running normal for a moment or 3.

Sprayed carb cleaner around the air intake boot at the throttle body, and the valve cover breather, moved the boot around while running, moved the wiring......stumbles and dies.

So it appears the wiring to the MAF or the Thottle Position Switch has something going on. I don't see anything right off, and with the way the cat all busted up and into the middle muffler, I could be battling the blockage of the exhaust.

First thing in the morning it's going to the exhaust shop that welded in their generic cat and I'll let them deal with the mess it made. Once the exhaust is fixed, I'll continue.

Please stand by:popcorn:
 

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So it appears the wiring to the MAF or the Thottle Position Switch has something going on.
Hmmm no MAF on these (that I know of). I believe they're MAPs (and in the ECU...follow the vacuum hose going to the ECU). However there is an intake air temperature sensor in that rubbery boot and that also can come into play with this.
 

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Discussion Starter · #20 ·
Riiiiiight.....show's you what I still don't know about EV's.

Yes, it's a "thermister" there in the intake boot, and yes, the ECU does have the pressure sensor inside. In fact, I replaced that long vacuum hose that feeds the ECU and while I was there, made sure the MAP inside the ECU held a vacuum. On the TDi's, it's not uncommon for that short piece of hose inside the ECU to fail, and then it's a CEL nightmare that looks like the ECU is bad.

So here's what I've found:

-The shielded wire to the OXS Sensor had a big crack/break in it, up near the intake planum. I cut that bad section out, but even with it cut out, so the computer was getting now OXS input, the engine wouldn't run for more than a minute or two before it developed a crazy stumbling misfire, died and would barely restart, if at all. All sorts of fuel pressure and flow, so that narrowed it down to 2 things.....fuel at the injectors, or spark.

-Well, I decide to pursue spark since when this all started barely 2 months ago, the first thing I did, based on the symptoms, was throw a new coil at it. It was a Meyle version, and I know better than to use their crap, but I thought, seriously, how bad could it be. So step 1 was to plug the old coil back in. The engine immediately fired up and ran beautiful.:mad: I plugged the fuel injection harness connectors back into the air temp, and throttle switches, and it ran even better. I left it run while I repaired the OXS wires, and it continued to run perfectly after I plugged the repaired OXS harness back into the OXS.

Once again, it appears to be fixed. It's over sunning itself at the exhaust shop right now, waiting for a new cat, and it'll probably get both mufflers too if they can't get the pieces of the cat out of them. That's fine. It's a brand new Bosal system, and I've hated it since about a month after installing it. It's really buzzy, especially when you wind up this great Audi 5 cylinder. Not cool.

I'll update more as I know more.
 
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