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  #1  
Old 02-06-2014, 07:55 PM
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SVX can't climb hills

I put it up on one of the Facebook pages and got some answers, but I figured I'd put it here if you guys have any more ideas.

So I let my roommate borrow the car to go to work and I got the call this afternoon that it stalled out on him on the hill coming right up to the dorm buildings. So I walk down to him and the car starts up (while sounding very rough), but when I put it in gear, it would just stall out. It was a busy road and I couldn't roll it back down the hill, do I held the brakes and rev'd it to about 2k and let go. This got it to climb a bit until it stalled again. I repeated this (while crying on the inside) a few times until I got to the dorm about 100 feet up the hill.

Once I got it parked, it coughed a good bit while starting, and if I would try to rev it in park, it filibustered it's way to around 3k and just died around there. I checked the codes, even though no CEL came up. I got a code 37, which has been there before, and I knew the ground under the ignitor was pretty rough, so I cleaned it up nicely and dielectric greased it.

I also have a spare MAF from a 90's something auto Legacy, so I plugged that in to test. No big difference there.

After the ground was done, it rev'd very well when parked, started easily, and sounded great, so I took it for a 5 mile test run with some moderate hills, but mostly flat. I stopped on some of the hills, and it took off with very little throttle or wide open. On flat ground, it takes off like it never has before. There is no hesitation, the throttle response is almost instant whereas it would fall on it's face before. The power is also very smooth and the butt dyno completely freaked out because it's never ran this well for me.

The test drive went well, so I was feeling confident when I tried to climb the same hill. It was longer and steeper than any on the test run, and starting about 50 feet up this 200 foot hill, I could tell something was off. There was no power at any throttle, and it barely coughed back to the parking lot. There was no CEL, from beginning to end.

So between what I've been thinking and what I've seen on Facebook (Thanks, Nate), the possibilities are:

1: Timing is off
2: Vacuum leak
3: It's the O2 code that the ECU has stored?
4: Throttle Pos. Sensor
5: Coils

I'll go out tomorrow or Saturday and spray around looking for vacuum leaks, but where do I even begin to diagnose the other possibilities?


Thanks again for all your help, guys. This thing would still be stuck and undrivable if it weren't for the info you guys have shared. Thanks for putting up with the long post.

-Randy

TL;DR: I accidentallied the whole car. Please halp.
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  #2  
Old 02-06-2014, 08:46 PM
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Re: SVX can't climb hills

Up hill = under load = taxing on the coils

Cleaned ignitor ground = better performance = ignition circuit

I'd check the coils, the harness/connectors going to the coils and ignitors.


Good luck
Bill
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  #3  
Old 02-06-2014, 11:10 PM
Chucksta Chucksta is offline
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Re: SVX can't climb hills

Gonna really, really reach on this one

"On flat ground, it takes off like it never has before. There is no hesitation, the throttle response is almost instant whereas it would fall on it's face before. The power is also very smooth and the butt dyno completely freaked out because it's never ran this well for me."

Hmm.. to me, that would seem that it's not about "pull", or "load".. The variable seems to be the STEEP hill. Dumb question, but how much gas is in her, and is there a bend as you enter the steep hill. As the SVX has a saddle type fuel cell, there's a funky jet pump thingy to keep fuel on both sides of the saddle. Maybe it's not transferring fuel from one side back to the other when you're nose up, because the symptoms sound a lot like fuel starvation. Unfortunately, you'd need a fuel pressure gauge run back inside to check rail pressure when she dies out. Or.. Hmmm... I didn't catch what year it was. If it's after '94, it's be OBD2. I don't know if they read fuel pressure or not. If they do, it'd be easy to check.

Of course, if you've got 3/4 of a tank, that idea goes out the window. If you're almost on "E".. fill 'er up and that eliminated any possibility of it being a tank supply issue.
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Old 02-06-2014, 11:29 PM
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Re: SVX can't climb hills

Around 3/4 tank in her right now. I was thinking along those lines, but she has climbed that hill many times before when running on fumes.

It's a 92, so no OBD 2 for me
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  #5  
Old 02-07-2014, 04:47 AM
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Re: SVX can't climb hills

Smells to me also like a fuel starvation problem also. Has the fuel filter been changed in the last 10 years ? Can you run her on flat ground/Interstate at 80 mph without any symptoms, running her up to near redline in 2-4 gears ?

Have you checked the undercarriage where the hard lines run to make sure the feed/return lines to the saddle tank haven't been pinched by hitting a foreign body or a nice chunk of ice hardened by your single digit nights up there !

Then there's a failing fuel pump but don't this so....you would think driving in 1st gear on flat ground would mimic any steep hill conditions you would encounter.

Good luck...
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  #6  
Old 02-07-2014, 07:48 AM
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Re: SVX can't climb hills

Fuel Filter has around 400 miles on it. While it was running on flat ground and going up one of the not as steep hills in my test, I womped on it and she did spool out to redline on multiple occasions. I can't stress how much life it suddenly has lol.

I hit around 70 on the straightest shot and held it for about 30 seconds, no issues there. Revs were low and TC seemed to have locked.

Now because the roads were covered in snow and all kinds of other shenanigans, I wasn't sure of what it was, but just as I pulled into the parking lot and it lost all power, I thought I heard some clunks or bangs. Reminded me of my Legacy's Exhaust coming undone and hitting the ground. I got out of the car and checked under it and nothing was dangling or visibly mangled.

Once it got off the steep hill, all was fine again. Is there a possibility that my car is only fueled by voodoo magic?
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  #7  
Old 02-07-2014, 08:41 AM
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Re: SVX can't climb hills

Again no flashing of the green 'Power" light or CEL codes, right ? The Power light does show up with the key on "ON" ? Same problem with the other MAF you plugged in ? Any chance your MAF plug or wiring to it is buggered up ?

Have you checked the 4 large grey square connectors on the passenger side of the engine towards the rear ? Nice and snug, clean? Connector to the vehicle speed sensor on passenger side of tranny where it connects to engine ? Problem there should however have the Power light coming on and off. I had "clunks" when one of those 4 connectors was loose but also had "Power" light intermittent flashing.

Presume you checked the ground on P side of IM (12mm bolt)..

What happens if you try a test run with MAF disconnected...it should run off the default ECU programming. Doubt the O2 sensor if failed would cause these problems as you probably already thought.

I'm feeling electrical per what you've said so far if you get fuel at high rpms. Coil failure should be throwing CEL codes with "misfire cylinder 4", etc. type of picture. Your feeling has more zip now ...?...running a bit leaner than its usual too rich settings stock...try disconnecting the vacuum feed from the fuel regulator so it is max'd out all the time just for the hell of it.
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Old 02-07-2014, 09:13 AM
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Re: SVX can't climb hills

No CEL, no flashing power, but the light does come on with ignition.

With the MAF unplugged, it fires once or twice and dies. It starts on the second try with a CEL on.

I haven't checked those connectors yet and I haven't seen that ground on the intake manifold yet. I thought it was on the driver side, which explains why I haven't been able to find it.

Tonight, I'll check for vacuum leaks and I'll probably clean and reseat those connections (to the ignitor, right) and that ground since I have limited sunlight after class.

Keep the suggestions coming, guys, since my next backup plan is move to Nebraska. Nobody wants to move to Nebraska.
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  #9  
Old 02-07-2014, 10:30 AM
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Re: SVX can't climb hills

Those 4 connectors aren't near the ignitor..pass. side, look down towards the diff. dip stick and to the rt. a bit you'll see 4 grey square connectors together near O2 sensor upper connector.
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Old 02-07-2014, 11:41 AM
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Re: SVX can't climb hills

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Originally Posted by fasteract7 View Post
Those 4 connectors aren't near the ignitor..pass. side, look down towards the diff. dip stick and to the rt. a bit you'll see 4 grey square connectors together near O2 sensor upper connector.
Ok, I'll check those.

I did think of something else. The box part of the intake tube where it connects to the throttle body has 2 vacuum lines on the driver side. The bottom nipple looks to have leaked at one point and the previous patched it with some RTV (and not very well) If that has started to leak, that would explain any unmetered air coming in, so I'll double check that one.

Out of curiosity, does anyone know where that bottom driver side vac hose goes to?
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Old 02-07-2014, 12:07 PM
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Re: SVX can't climb hills

Gonna really, really,really reach on these, but, what the hell..

If it was electrical, as in the angle of the hill made some wire / connector, lose contact, then why didn't it immediately go back to running the way it always did once back on flat ground? Hmmm... It coughed and sputtered, almost as if it had sucked something nasty ( like water ) from the tank, and had to clear it out of the fuel lines. As water lands up at the bottom of the tank, if there's any in there, it may only be hitting the fuel pick up when the car is angled up on a steep hill. Fuel line anti-freeze works by absorbing the water in a fuel system.... Yeah.. that one is definitely a " stretch"

Climb the hill, let her die (as you pull over to the curb). Disconnect the injector fuel supply and then pump a bit out into a suitable container for inspection. That would establish fuel supply and quality.

Will it climb the hill in 2nd gear ( put the shifter in 3rd and press the "manual" button in). If it will, it would seem to indicate that an electrical communication issue between the TCU and the ECU.. Damaged speed sensor lead? You did mention a "thunk" and her dying out, pulling into the parking lot. Intermittent short?

Will it climb the hill in reverse? That goes back to condensation in the fuel tank.


Disconnect the battery..

it's not "voodoo magic".. Think of it more as an exorcism
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Old 02-07-2014, 12:14 PM
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Re: SVX can't climb hills

This hill's the main stretch of campus, so I can't keep testing and failing lol. So my main battle plan is to put some work in tonight and tomorrow and then head towards the mountains this weekend to find a nice, isolated hill.

If the ground and vacuum lines are good, I'll get it to die on an incline and then see what kind of gas is going into the filter.

I didn't try going up the hill in 2nd. I had traffic all around me , so I threw it into 1st Manual and gave her all she had.


As for fuel leaks, it has been pretty rough here lately, but I haven't smelled any fuel. And aren't the fuel lines run through the channel under the door?
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  #13  
Old 02-07-2014, 12:49 PM
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Re: SVX can't climb hills

Let's see who can go the farthest out on a limb (I'm still sticking with my original "check the coils" suggestion)...

How about hill=load=possible engine knock=pulling back enough timing that she doesn't want to "go"?

This is like negative bench racing...


Bill
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Old 02-07-2014, 12:54 PM
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Re: SVX can't climb hills

Quote:
Originally Posted by WhatIsThisIDont View Post
Ok, I'll check those.

I did think of something else. The box part of the intake tube where it connects to the throttle body has 2 vacuum lines on the driver side. The bottom nipple looks to have leaked at one point and the previous patched it with some RTV (and not very well) If that has started to leak, that would explain any unmetered air coming in, so I'll double check that one.

Out of curiosity, does anyone know where that bottom driver side vac hose goes to?
The bottom hose on the drives side is the drives side valve cover "pcv" connection, that hose does not go into the air box it runs under/through it and on the other side splits and goes into the pcv valve and the passenger side head
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Old 02-07-2014, 04:22 PM
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Re: SVX can't climb hills

Interesting so far..as far as the electrical connection, I thought the car ran pretty well in the flat except for the one time it dropped dead going into the parking lot. Most hills aren't more than a 7 degree grade.....if you jacked the front of the car to the max could you duplicate this condition (yeah, I know this is pretty weird and I'd be scared the darn thing would fall off the jack/jack stands if you rev'd her too hard.)

Do you have a multimeter you can check the coils with ?

The thought that you got a really crappy tank of gas so that there is a significant water level at the bottom is interesting..have no idea where the fuel pump pickup is located as far as towards the back/middle/rear of the saddle tank. Would think that when the engine is running poorly during your uphill episodes, you would see a fair amount of white exhaust discharge from excess water but maybe not enough water to produce that..I know a blown headgasket with antifreeze/H2O going into my VW produced a white cloud (no oil galleries were compromised).

Is there a drain plug on the bottom of our gas tanks to check if water comes out first?
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