Strange problem

iowasvx · #1 03-29-2009, 04:00 PM

3 weeks ago my wife filled the 94 svx with mid-grade with ethanol. Not sure if it has anything to do with the problem, but temporal related. Since that time car started to just die while driving. Would happen intermitantly during city driving. Car would always start right back up and drive fine. Started happening more often, then car quit at 70 mph on the interstate. All the dashboard lights come on, car starts right back up, might die again then starts and drives. It did lose power twice on the interstate but then kicks back in before it dies all together. My local shop I trust had the car for two days. Said no codes in the computer. They could get it to do the same thing but could not isolate the problem. Fuel pump checked out ok, all sensors, ignition switch and relays were ok. They think an electrical problem with an exposed wire or ground, but said they couldn't isolate unless the car died all together.

I had them change the cam shaft sensor. Still happening, but less frequently. Today I changed the fuel filter, cleaned the MAF sensor, changed the air filter and filled the car back up with premium and added some lucas gas additive.

Car still acting up but much less frequently. Any thoughts? At this point I am getting a lot of pressure from the wife to get rid of the car.

Thanks

svxfiles · #2 03-29-2009, 04:16 PM

Quote:

Originally Posted by iowasvx

3 weeks ago my wife filled the 94 svx with mid-grade with ethanol.

Do you mean E85?

If it's dying while driving I would suspect the MAF.

You can try one from a Legacy just to test it.

iowasvx · #3 03-29-2009, 04:22 PM

Nope, mid grade in Iowa is a 10% ethanol blend.

1986nate · #4 03-29-2009, 04:33 PM

Quote:

Originally Posted by iowasvx

Nope, mid grade in Iowa is a 10% ethanol blend.

Make sure to use premium always. Using anything other will almost always cause the ECU to adjust timing because it will sense pinging from the lower octane gas. Use 91 octane at minimum unless in higher altitudes, then you can get away with using lower.

This however, does sound something more electical signal related...

Manarius · #5 03-29-2009, 04:37 PM

Quote:

Originally Posted by svxfiles

If it's dying while driving I would suspect the MAF.

You can try one from a Legacy just to test it.

I would do that as well.

A JECS (plastic) MAF from a 90-94 Legacy will do the trick for testing purposes.

iowasvx · #6 03-29-2009, 04:59 PM

i will see if I can find a used MAF at the wrech and go before I plunk down another $280 for a new one.

Famouspork · #7 03-30-2009, 07:39 AM

Last thing you wanna do is listen to the wife.

b3lha · #8 03-30-2009, 07:52 AM

Sounds a lot like what happened to me when I picked up a load of bad fuel.

Chuckles · #9 03-30-2009, 08:31 AM

For years I worked for a privately owned Sunoco chain in Michigan. They would pour water in the tanks to dilute the gas, all the tanks were filled with the lowest grade available, and they always adjusted the fuel regulators so you appeared to pump a gallon or so more then you actually got. It messed up a lot of cars, but it didn't do that, that does appear electrical.

It would probably be cheaper to just buy some thick cable and redo your grounds and battery lines. It a lot cheaper, and frankly it probably needs doing anyway. Better fuel economy and performance at least, if not a fix to your problem. I like to use the super conductive jelly at the connection points too, its better for frame grounding i think. I did this on a few "lost causes" and they purred for many years after, free of issues. Anyway its worth a shot.

+1 for not listening to the wife

iowasvx · #10 03-30-2009, 10:11 AM

No go on the used MAF. The wrench and go people had no idea what kind of car I was talking about. I did, on a whim, last evening unhook the negative battery cable and let the car sit for 30min and rehook everything. Ran great this am, but again the problem is intermittant.

As far as the grounds, I would love to replace them, but not sure how this is done. Couldn't find any info in the how-to section. Does anyone have diagrams or info on how to get this done?

At some point I am bound to get the right combination of things replaced or fixed on this thing.

iowasvx · #11 03-30-2009, 12:17 PM

I think I might have this figured out. I can get a replacement battery cable cheap at the autoparts store. Then if my reading is correct I have two grounds to the negative terminal. One to chassis and one to engine. Just need to trace these back and replace the wire. Is 4 gauge adequate?

bheinen74 · #12 03-30-2009, 12:53 PM

I only put Amoco /BP ultimate or else Phillips 66 Premium in. Most other gas here in Iowa is actually over 10% blended with E.
But the Ultimate and Premium is not ethanol.
I think you got a bad batch of gas. Don't go to that station again, or else use the premium. It will take several tanks to get rid of the bad. Educate the wife in a friendly way to only use premium, like 80 percent of gas places here don't have premium, you have to hunt them down
The owners manual on my SVX strictly warns this "do not use fuel containing more than 10% ethanol, damage to engine will occur"

dcarrb · #13 03-30-2009, 02:49 PM

"Bad gas" is possible, but it seems after three weeks and a fresh tank you'd be back in the pink by now.

Not to discount any one else's experience, just as a matter of fact, I have for years topped-off my tanks with 87 octane, cheapest stations in town, up to 1/2 tank at a time, including 10% ethanol blends (aren't most?), and have experienced no drivability problems. (Premium here is 93 octane, so a 50/50 regular/premium mix works out to 90 octane, anyway, but it's not like I use graduated beakers to achieve a perfect mix). I don't think fuel quality is the issue here.

Yes, the owner's manual blesses up to 10% ethanol. No to methanol.

dcb

iowasvx · #14 03-30-2009, 08:06 PM

OK just replaced the battery cables and grounds. Car running perfectly on the test run. Only time will tell now. Thanks for all the help.

Blacky · #15 03-30-2009, 10:25 PM

Quote:

Originally Posted by iowasvx

I think I might have this figured out. I can get a replacement battery cable cheap at the autoparts store. Then if my reading is correct I have two grounds to the negative terminal. One to chassis and one to engine. Just need to trace these back and replace the wire. Is 4 gauge adequate?

4 gauge is perfect. The chassis ground from the neg. battery terminal just goes down and to the front corner of the battery. You can run another ground from the A/C bracket to the negative terminal on the battery. Here's more info, go to post 5:http://www.subaru-svx.net/forum/show...ernator+wiring