Topic: Hesitaton at WOT

[YKWRX]

The best I can think to describe this is as a hesitation in my jdm bugeye wrx, when WOT in 2-3 gear above 3500 rpm, and at random. The car will feel like it cuts fuel/hesitates, then goes again, then cuts, repeat and is sometimes accompanied by a boost spike.  Started in the winter after driving fine before, only changes made were walbro 255, ebcs and tune due to only having access to 91 gas and not wanting to run the car with stock tune for japans higher octane fuel.

Mechanic up here thinks it may be a stuck/dying injector, but before i dive into that bottomless pit of replacing/upgrading parts has anyone else had a similar thing happen with their car, jdm or not?

[jellynuts]

Probably too simple to be the fix, but have you tried cleaning your MAF?

[RockThePylon]

Could be the 'ole classic - spark plugs. I always recommend starting there. Remove and inspect gap.

[WAGOWN]

That sounds like it might overboost fuel cut.  Do you have a boost gauge? Really look hard for cracked boost lines. Like remove them and bend and check. Could also be a sticky/malfunctioning boost control solenoid.

Jellynuts might be onto something too. Dirty MAF is common and can cause that kind of symptom too.

Doubt it’s plugs, it hardly ever is. This seems like a boost issue. Easy to check for peace of mind though.

[reet]

On the older cars like my v1, this was a common symptom of bad coil packs. On a 2000 model it should be easier to troubleshoot, the engine codes should tell you about a misfire and which cylinder. It could be a bad injector, coil pack, spark plug, you get the idea.

[kijho]

Spark Plugs -> MAF -> Fuel Filter -> Fuel Pump -> Injectors -> Coil Packs - > IACV

If you have not done coil packs before that should be one of the first thing upon importing a JDM (They're usually pretty worn as they are, and then shipping causes them to worsen.)

If you haven't looked at your MAF, there's a lot to be research on these. Buy some cleaner from Canadian Tire (I think it's throttle body cleaner?) Try that.
 
Then look further into issues with the MAF such as pins becoming un-soldered beneath the housing (I had this issue, re-soldered pins helped.)

If you want to look at the IACV be sure to order a new gasket, they're ~ $5. I am not sure the part # though so look that up beforehand. It's old and falls apart.

Does the '00 JDM's have the self diagnostics CEL Codes? On my old GC8 there were 2 connectors beneath the steering column which when you connected them and turned the car to 'ON' the CEL would flash XX number of blinks.  (Ie. # of blinks = ___ problem.)   The problem I found with that, is that IACV/ MAF/ etc. were all triggered by the same issue so it would light them all up. So I just changed everything

Goodluck!

[cmyles]

Spark Plugs -> MAF -> Fuel Filter -> Fuel Pump -> Injectors -> Coil Packs - > IACV

If you have not done coil packs before that should be one of the first thing upon importing a JDM (They're usually pretty worn as they are, and then shipping causes them to worsen.)

If you haven't looked at your MAF, there's a lot to be research on these. Buy some cleaner from Canadian Tire (I think it's throttle body cleaner?) Try that.
 
Then look further into issues with the MAF such as pins becoming un-soldered beneath the housing (I had this issue, re-soldered pins helped.)

If you want to look at the IACV be sure to order a new gasket, they're ~ $5. I am not sure the part # though so look that up beforehand. It's old and falls apart.

Does the '00 JDM's have the self diagnostics CEL Codes? On my old GC8 there were 2 connectors beneath the steering column which when you connected them and turned the car to 'ON' the CEL would flash XX number of blinks.  (Ie. # of blinks = ___ problem.)   The problem I found with that, is that IACV/ MAF/ etc. were all triggered by the same issue so it would light them all up. So I just changed everything

Goodluck!

This guy knows whats up.
I had the same issue in my 01 JDM Forester and it turned out the be spark plugs. MAKE SURE THEY'RE GAPPED PROPERLY.

[Coops1313]

+1 for spark plugs

[FresH599]

I had the identical problem with my jdm bugeye.
Did you check for any stored codes?
I tried plugs/ coil packs then a tune but it turned out to be the front cam sensor.
I replaced it and viola.