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  #1  
Old 11-25-2002, 05:23 PM
Shadow248 Shadow248 is offline
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Starts really hard.

This has been a problem on Mandi's SVX ever since she got it:

on 8 out of 10 starts, it takes an unusual amount of cranking to start the engine. Almost to the point that I start to worry about the poor starter having to crank so much. I have tried turning the key to RUN and letting the fuel pump run for a few seconds before starting, and this makes no difference. It doesn't matter if it's cold or warm (engine or air), and there seems to be no other sort of pattern.

Any clue? If I pump the gas pedal it helps A LITTLE. But it's still bad.
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Old 11-25-2002, 06:23 PM
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Pumping the pedal should have no effect, maybe it justs gives you something to do while waiting for it to kick over.

Have the fuel pressure checked, while waiting for it to build up is a good idea it doesn't mean that it's actually reaching the pressure required. Normally a weak pump or clogged filter will show up at high-speed/high-load conditions though.

Have you checked the basics? Spark plugs, fuel and air filters, etc. That is always where you should first start. After that I'd be inclined to check the crank sensor signal, some cars have a tendency to start poorly if the sensor weakens with age and doesn't provide a strong enough signal. Some cars (Jeeps are notorious for this) need to crank and crank until the sensor builds up a required voltage.

If this is all greek to you, start with the basics and if the problem still exists, find a reputable driveability tech.
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Old 11-25-2002, 08:44 PM
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The plugs and air filter have about 4,000 miles on them. Though i haven't checked the air filter lately, seeing as this hasn't changed in a year or so, i don't think that's the problem. I would check the crank sensor, if i knew where to find it. I know how to check it using a DMM, but where do i find this sensor? and is there anything special about it that i should know? (as there is with so many other SVX parts).

Thanks for your help. The local subaru dealer has serviced the car several times and never said a word about the starting problem, which i thought they would notice quickly. I will stop by there as soon as i can.
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Old 11-25-2002, 10:20 PM
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Yeah, it's funny that most techs are paid by production, yet they're too lazy to mention the obvious problems each car has. I'd rather spend my time on the cars with owners wanting to keep them in good shape than a bunch of rolling dumpsters that just waste my time.

Anyway, back to your problem. Instead of running down each sensor how about trying this: An engine requires three things to operate, air, fuel and a spark. The air is controlled mechanically by the pistons, valves, timing belt, etc. If the car eventually starts and has good power once it's running, we'll consider the air to be working as planned.

You stated the plugs only have about 4000 miles on them. As long as nothing terrible has been gong on we'll assume they're o.k. What I would suggest is to obtain or make a 'noid' light, basically a 12v led test light. The reason I recommend this is, unless you have a high-end, graphing DMM or at least one that can read/display frequency or pulse-width, you'll run a chance of missing the pulses. A couple bucks at Radio Shack for a 12v led and some wire to extend the leads will work. Seeing how the SVX has six coils we'll assume that they're o.k. as it would be difficult to believe that all six would fail simultaneously. So what we'll do is back probe the connector of a coil, preferably the easiest to reach. FYI, back probing means slipping a stiff pin along the wire and into the back of the connector - piercing wires is a no-no, it can cause problems later down the road (corrosion, etc.) The coils are always hot when the key is on and the computer switches their grounds on and off to fire them. So the thing to do is to back probe the odd colored wire (the power comes in on the Black/white wire at all coils) and connect the other end of the test led to the battery positive terminal. Watch for flashing to indicate it as firing, as soon as the engine begins spinning. If it doesn't flash immediately as the engine revolves we've found at least part of a problem.

Next we'll want to do the same test with an injector. You did check the fuel pressure beforehand, didn't you? Anyway, bridge the injector with the noid light and crank the engine (actually you can completely disconnect the injector, or coil for that matter, and avoid back probing.) You'll have to watch closely as the flash will be faint and very quick, but discernible. Typical injector pulse width at idle is around 2-4 ms., but you can see it. Again, if the pulse doesn't occur immediately we're on to something.

Do these checks and report back, it'll keep me from writing a book. (this isn't the first long post I've written.... )
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Last edited by Beav; 11-25-2002 at 10:23 PM.
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  #5  
Old 11-26-2002, 09:59 AM
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http://www.subaru-svx.net/forum/show...2901#post72901

I have the same problem. I will try Beav's suggestions and report back.
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Old 12-03-2002, 08:57 PM
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I'll give it a try. Usually I only see the car on weekends, but this week i have it all week, so i will try to get time to do this.
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  #7  
Old 12-04-2002, 08:32 AM
AutoTchr AutoTchr is offline
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Another thing to try would be a cold compression test. But one thing is not clear....how does the car run when it does start?
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Old 12-04-2002, 10:02 AM
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In my case, once started the car runs awesome.
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  #9  
Old 12-05-2002, 08:19 PM
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My obvious suggestion is to check for engine codes. Is it harder to start when it's colder out (near freezing)?
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