Ground issue possibly? need guidance

[93GC8Dub]

So with my 93 gc8 wrx i have recently been having issues with what seems to be an electrical issue, the symptoms are
-no throttle response
-dash cluster rpms drop as if there is power loss but speedo and others dont move,
-car will travel down the road in gear but throttle doesnt give a response(doesnt jolt)
-the car seems more likely to do this on bumpier roads it seems(although today it happened on a highway) it slows down but then will become responsive again shortly after.
-Doesnt toss any cells or codes

Recently i have done a sub into my car, perhaps a voltage issue?

Any ideas guys?

for now im gonna remove the subs and see how it acts.

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[TommyAtomic]

I have a 93 wrx myself. Think logically. Its 19ish year old car. If its acting up start with basic maintenance.

Oil change
New plugs properly gapped
new fuel filter
clean MAF
clean the throttlebody
Clean battery terminals and have battery tested
check alternator voltage
clean up the factory grounds
check all vacuum lines for cracks or leaks
clean your crank sensor
check your coolant levels

Check the condition of your coilpacks. If they are original check for cracks and look into the coilpack upgrade.

I'll not argue the possibility that you have electrical issues made somehow worse by the installation of your sub. I can say no-one across teh internet can help you with a completely random electrical problem as well as an actual mechanic in person. How your car responds to basic maintenance will tell you alot about whats going on with your car when it acts up without a CEL.

If you installed a big amp or sub with alot of power draw it may have damaged your battery or alternator. Most audiophiles do whats called the big3 upgrade which is basically a replacement large gauge (like 0) an additional large gauge (like 4) power cable from the battery to the alternator as well as additional large gauge grounds running to the battery, chassis and engine. This reduces electrical resistance and decreases strain on your battery and alternator.

All of that is a maybe, conditional on the maintenance level of your vehicle

[69subaru360]

Could be a bad oxygen sensor.

[93GC8Dub]

Originally Posted by 69subaru360

Could be a bad oxygen sensor.

mmm i dont know about that i just replaced the 02 sensor maybe 2 months ago with a bosch replacement that clipped right in! and i was getting great milage...can you tell me why the 02 might be the culprit(for sake of arguemnt)

[93GC8Dub]

I have done all this stuff within the last year
-MAF
-fuel filter and pump
-water pump
-timing belt
-plugs(not so recent, gonna do this weeked)
-02 sensor
-thermostat
-injectors
-ECU(rob 550)
-EBC required a few new vac lines
-coilpacks

ummmn i think that sums it up

when the car is acting up and becomes restonsive to throttle if i put my foot to the ground, it will accel hard and then its almost like fuel cut, and sputters again...but it only acts up for a few seconds then becomes normal. but on bumpy roads, more apparant, especially gravel roads

[93GC8Dub]

Oil change
New plugs properly gapped
new fuel filter
clean MAF
clean the throttlebody
Clean battery terminals and have battery tested
check alternator voltage
clean up the factory grounds
check all vacuum lines for cracks or leaks
clean your crank sensor
check your coolant levels


why might coolant level have to do with the equation(just did a coolant flush) the issue was happening prior

[69subaru360]

Originally Posted by 93GC8Dub

mmm i dont know about that i just replaced the 02 sensor maybe 2 months ago with a bosch replacement that clipped right in! and i was getting great milage...can you tell me why the 02 might be the culprit(for sake of arguemnt)

Surging at cruise is often the O2 sensor. I never have good luck with bosch ones in subarus.

[eg33GC]

Denso is the only 02 i've ever used in 0bd1 subarus, and for good reason.


Your entire closed loop operation is based on the 02 sensor.

[i_c_the_light]

You've got a loose wire somewhere. Where the loose wire is...well...**** knows.