Has anyone experienced an SVX engine running perfect until it reaches 2000 RPM, and then it misfires, "Bad misfire" and have you discovered what it caused it?

Has anyone experienced an SVX engine running perfect until it reaches 2000 RPM, and then it misfires, "Bad misfire" and have you discovered what it caused it?

I bet it's a coil pack. As for which one, you'll have to see if you can isolate it down to which coil pack is bust.

 

Although, how long has it been since you've changed sparkplugs?

Tried it. They are good. Remember it runs perfect and hits a wall at 2000 to 2300 RPM. Plugs have been changed and are clean... I am lost with this one...

I have no experience with your problem. I had coils go bad and it was worse at idle. The car needs air, gas and spark. Does it do it when your sitting still? Try the gas pressure maybe it's dropping off or the ignitor pack.

OK above 2300 RPM? Throttle setting (WFO, gentle acceleration, cruise) have any effect?

 

I have had dead zones in the power band of a EA82T caused by a bad sparkplug wire: Worked Ok until some combustion/sparkgap stressor required more voltage than the secondary system could provide.

There may be a bad spot on the TPS sensor causing this. You could monitor the voltage to the ECU to see if that is correct.

I see no mention of ignition wires.

 

I would think coil.

 

HOw old are the plugs.

 

This sounds like an ignition breakdown to me. It oonly does it under load when hot?

 

nipper

I see no mention of ignition wires.

 

I would think coil.

 

HOw old are the plugs.

 

This sounds like an ignition breakdown to me. It oonly does it under load when hot?

 

nipper

 

the SVX uses coil-on-plug DIS, no ignition wires.

might post this up at http://www.subaru-svx.net/forum/

 

From what I understand, it totally falls on it's face at 2000 RPM, it doesn't just develop a miss? I'd start with the fuel filter, and if that doesn't do it, check your fuel pressure, and make sure you don't have a plugged air filter and all your hoses are tight.

 

Also, the SVX has a twin runner intake, there is a valve in the center (It's under the black plastic strip in the center of the upper plenum) make sure that is connected and working, I don't know if it would make it fall on it's face if it didn't open at the proper RPM, but it would definitely affect it.

 

You might also check the air flow meter, although usually those will cause the car to randomly stall out when they start to fail. There is a write-up on the SVX World Network about re-soldering the joints in the air flow meter, which is usually what causes them to fail (cracked solder joints).

 

You could also have a flakey ignitor, not 100% positive as I have not hunted for mine, but I think it is mounted to the firewall inline with the throttle body.

ah yes thats right no wires.

ah yes thats right no wires.

+1

Having 3 of them, I really should have remembered.

just throwing these out there, but could we be looking at a timing belt off a tooth, or a plugged cat? both of those can seem to run just fine at idle, but fall on their face when they get into the revs...

just throwing these out there, but could we be looking at a timing belt off a tooth, or a plugged cat? both of those can seem to run just fine at idle, but fall on their face when they get into the revs...

Plugged cat you would hit a wall, and never get past that point. Timing belt is interesting...

 

nipper