Vanagon with SVX running poorly - help diagnose! SOLVED!

[swissarmychainsaw]

I don't this this is related to my problem, because the Van has been running progressively worse over the last couple years (and I'm not using it much) - But I need to include it:

Went out last summer and ripped a hole in the coolant line and it got hot while we figured out what had happened (fans were not kicking on). I don't think I ran it catastrophically hot, but it's a data point I can't ignore.
Oil looks good. Coolant looks good.
The problems below PREDATE the getting hot episode, mostly. But it's gotten worse and lacks power so bad now I don't drive it. I drove it to the East Bay from Truckee with no problems and it had power, cruised on the fwy, no overheating, etc.

Symptom:
Runs like crap. NO power. Exhaust smells bad. Some "fluttering" at the exhaust.
Used to be that it would "run like crap" but if you got the RPMs up it would wake up (like its not firing on all cylinders).

Idle is slightly rough, but not crazy, but I would expect this SVX 3.3 six to idle like a sewing machine, and it does not do that.

It really feels like its not running on all cylinders.

Today I finally get to pulling the codes (no Check Engine light so I had to set that up for testing).
Put the fat shielded blue wire into the black connector (to the blue wire w/white stripe).
Codes looked like this:

17 Fuel Injector No. 4
23 Air Flow Meter or Circuit

32 Oxygen Sensor or Circuit (No. 1, Right Side)
37 Oxygen Sensor (No. 2, Left Side)

14 Fuel Injector No. 1
15 Fuel Injector No. 2

So to me that's crazy and I'm thinking I'm either screwed or it's something that they all have in common. "This looks like a bad ground", so I try and check the grounds and end up using a jumper cable from the NEG BAT terminal straight to the motor (unhooked the vanagon battery ground (old crusty thing).

End up clearing the codes by disconnecting the battery for like 10 mins or so.
Take the Blue wire out of the black plug (Code Tester)
But I leave the CEL hooked up.

Key to the ON position, CEL lights up.
Start Van - CEL goes off.
This tells me that I have no stored codes and that the Van is not generating new codes either.

Test drive, and it still runs like crap, but the CEL does not get triggered!

Did a rodent crawl into my tailpipe and die? I'm kinda stumped.

Thanks for any help!

[Mikesarge]

Diagnosing this via internet is really difficult. Codes may not come back immediately, so they may tell you something if/when they come back.

All of that being said, “Exhaust smells bad” and worsening performance over time would tend to indicate a failed/clogged catalytic converter. Can you easily bypass the cat(s) for diagnostic purposes and see how it runs?
_________________
1986 Syncro westfauxlia EJ-frankenmotor
1980 911 SC 3.1

[Captain Pike]

Check your coils. All 6. Then MAF.
_________________
LEARN TO SELF RESCUE
59 Panel bus, 1966 Single cab. 73' 181. 73 Westy. 91' H6 Vanagon 3.3L.
....Bad Sneakers....

[swissarmychainsaw]

I'm trying not to remove the intake manifold for now. I do believe this is a SmallCar header (not stainless) but I know the conversion was done by them.

Ok here is my new "Scientific Method" set of tests.

Check for Exhaust Header leak | cheap and easy first!
Check Coils | Ohm & use a spark tester | Ordered tester
Check MAF | Multi-meter tests
Grounds | Add a fat ground wire from BAT NEG to engine block, clean others. This currently has extra ground wires from the intake to the chassis and from the block to the trans.
Injectors | pull one injector wire at a time (after checking coils)
Check Cat | disconnect the muffler/Cat at the Y-pipe and test drive | Yes I"m that neighbor!

[hdenter]

I can't say what test or order would be appropriate for an svx, but do them one at a time and observe results. Doing multiple things and having a change(good or bad) just causes more confusion. Good luck!

P.S. How are registering/smogging that SVX in S.F.?

Hans
_________________
'79 triple white convertible bug
'84 sunroof vanagon
'85 weekender

[swissarmychainsaw]

[E1]

What were the results of disconnecting the cat?

Have you taken temperatures readings of the cat?
_________________
If ever twice as rich, we’re gettin’ a double-wide
’84 “Westfailure”/2.1 Digijet/5.43 Ring & Pinion/Peloquin/D-rated BFG KO2s

AI has spoken to further illiteracy, to steal, to cheat, and to replace humans
The caveman’s first question to the headhunter: “Hey, you got any coffee?”

[MarkWard]

Start with the basics. Pull the plugs and do a compression test. You can throw parts at it all day and accomplish nothing if you are down on compression in a couple cylinders. You stated you cooked it accidentally.

Also, the radiator fan needs coolant circulating to turn the radiator fan on. You stated you lost coolant. That would have allowed the overheating without the radiator fan ever knowing. So for now, remove that from your troubleshooting for drivability.

[kamzcab86]

[E1]

Agreed… and both parts failing in that exact order.
_________________
If ever twice as rich, we’re gettin’ a double-wide
’84 “Westfailure”/2.1 Digijet/5.43 Ring & Pinion/Peloquin/D-rated BFG KO2s

AI has spoken to further illiteracy, to steal, to cheat, and to replace humans
The caveman’s first question to the headhunter: “Hey, you got any coffee?”

[Howesight]

I suggest:

1. That you start by changing all the spark plugs. (That's a good time to do a compression check also.) If you have low compression on one or more cylinders, this may be due to a stuck valve (usually intake) due to bad gasoline causing a valve to stick slightly open. This can cause an odd-sounding exhaust note.

2. Then run the engine at idle and, one at a time, disconnect the wiring connector to one injector at a time and note whether the idle speed decreases or the engine runs rougher. If so, that cylinder is not "dead" This will give clues about which cylinders are affected, although you already have some data from the DTC's.

2. Note that the above approach will not necessarily tell you, for the "dead" cylinders, whether lack of fuel or lack of spark is the problem.

3. For the cylinders that appear "dead" install new coils. O'Reilly's sells them. They are a wear item in the end and are cheaper and faster to replace than injectors. Most SVX owners did not service the failed coil wire looms, which allowed the coil wires to flop around and cause a fail at the coil.

4. If you still have issues (and the compression test gave acceptable results), then you can consider injector clogging from old gasoline causing varnish compounds in the injectors. The best approach is to send your injectors to an injector cleaning service, not to replace with aftermarket injectors.

5. My guess is that a misfiring cylinder caused enough unburnt HC in the exhaust stream to both clog the oxygen sensors and also cause the CAT to clog or fail. So, once you get the engine running fairly smoothly again, both of the oxygen sensors and the CAT will need to be replaced.

I had this very problem with a coil failure in the middle of nowhere heading home to Vancouver from Syncro Solstice years ago. I disconnected the injector wiring on the cylinder with the failed coil, but that left the oxy sensors and the lambda control adding fuel to the 5 "good" cylinders to correct for the excess oxygen. Once home, inspection showed the (admittedly older) oxy sensors were clogged from only about 60 miles of running in this condition to get to the O'Reilly's store in Twin Falls Idaho.
_________________
'86 Syncro Westy SVX

[E1]

^^^ !!!
_________________
If ever twice as rich, we’re gettin’ a double-wide
’84 “Westfailure”/2.1 Digijet/5.43 Ring & Pinion/Peloquin/D-rated BFG KO2s

AI has spoken to further illiteracy, to steal, to cheat, and to replace humans
The caveman’s first question to the headhunter: “Hey, you got any coffee?”

[swissarmychainsaw]

Some updates ...


Compression test
right bank: 182, 180, 182
left bank 150, 151, 150


All six coils are showing fat spark with my coil tester (Lisle Coil-On-Plug Spark Tester - 20700)
Exhaust headers are not leaking.
Pulled the MAF plug and the Van dies immediately (a good sign).

Note the CAT is on the LEFT bank... wonder if that supports the blocked CAT theory...

Will continue tomorrow, will test voltage of the MAF, and go down the list:

Check MAF | Multi-meter tests
Grounds | Add a fat ground wire from BAT NEG to engine block, clean others. This currently has extra ground wires from the intake to the chassis and from the block to the trans.
Injectors | pull one injector wire at a time (after checking coils)
Check Cat | disconnect the muffler/Cat at the Y-pipe and test drive | Yes I"m that neighbor!

[Witless Joe]

Are you using the stock SVX ECU? Would it be possible to data log this thing with an Evoscan cable or similar?

https://evoscan.com/product/subaru-select-monitor-i-suits-all-1990-1998-subaru-vehicles/

Just basic checking for CEL codes seems pretty limiting.

I don't know anything about the SVX or EG33-converted Vanagons, but our other vehicle is an '08 Legacy, and RomRaider logger is the bees knees for accurately figuring out issues with that thing. Pretty sure that RomRaider won't work with that vintage a Subaru engine, though.

[E1]

Tests are great and sometimes needed, but it takes less than a minute to pull over and take cat temps.

Absolute computer reliance as a first course of action is like testing a calculator instead of just learning to use it.
_________________
If ever twice as rich, we’re gettin’ a double-wide
’84 “Westfailure”/2.1 Digijet/5.43 Ring & Pinion/Peloquin/D-rated BFG KO2s

AI has spoken to further illiteracy, to steal, to cheat, and to replace humans
The caveman’s first question to the headhunter: “Hey, you got any coffee?”

[swissarmychainsaw]

[Captain Pike]

Injector dribble
_________________
LEARN TO SELF RESCUE
59 Panel bus, 1966 Single cab. 73' 181. 73 Westy. 91' H6 Vanagon 3.3L.
....Bad Sneakers....

[E1]

[Captain Pike]

Left bank 30 down across the board? Testing with the throttle body open? 'Jector plugs off, WOT. See if you even out. Be sure both butterflies are opening at the same time. Test the TPS.
Did you build this or already converted?
The O2 faults may be wonky injectors or a plug not firing..
The CAT should be down stream from a y connection.
_________________
LEARN TO SELF RESCUE
59 Panel bus, 1966 Single cab. 73' 181. 73 Westy. 91' H6 Vanagon 3.3L.
....Bad Sneakers....

[swissarmychainsaw]