WRX not liking high revs!!!
#1
WRX not liking high revs!!!
Hello.
I have a MY95 WRX with the following mods -
K&N Induction filter
XS Scoobies DP (Decat)
Afterburner Center (Decat)
Afterburner Vortex BB
VTA Dumpvalve
Run on BP Ultimate or Optimax with octane booster every tank.
The problem I am having is when accelerating hard in any gear, the car will rev freely to around 5K when it will misfire giving a sudden jerk and a loud pop + flame from the exhaust then carry on until around 6K where it sounds as if it has hit the limiter. Whilst all this is happening the boost gauge reads 0.9bar.
Is this a problem with fuelling, plugs, overboosting or detonation.
btw - Knocklink is my next mod.
Cheers for any advice
Paul
I have a MY95 WRX with the following mods -
K&N Induction filter
XS Scoobies DP (Decat)
Afterburner Center (Decat)
Afterburner Vortex BB
VTA Dumpvalve
Run on BP Ultimate or Optimax with octane booster every tank.
The problem I am having is when accelerating hard in any gear, the car will rev freely to around 5K when it will misfire giving a sudden jerk and a loud pop + flame from the exhaust then carry on until around 6K where it sounds as if it has hit the limiter. Whilst all this is happening the boost gauge reads 0.9bar.
Is this a problem with fuelling, plugs, overboosting or detonation.
btw - Knocklink is my next mod.
Cheers for any advice
Paul
#2
A KL is really only for det problems. I'm not expert, but it sounds like a fueling problem or MAF issue. Lots or people have mentioned good results when they change or clean the MAF as it tends to pick up a load of crap after a while.
#5
First of all take away your dumpvalve, either fit a standard one or remove it and block the pipe.
If it's still doing it I would suggest it's an ignition problem, so the first stop is to try revving the car through at low load, so try pulling away in 1st and getting to 7000rpm with no boost (say 1/4 throttle). If that's okay then remove the coilpacks and plugs as they are likely to be causing low spark strength on at least one cylinder. Check the coilpacks for signs of cracking, and that the plugs are all there (not melted) have no significant deposits and are gapped to 0.7mm. Try new plugs if you don't know the history of the current ones.
If the new plugs don't sort it, get some new coilpacks, or a few and try replacing 2 at a time to see if you can fine 1 or 2 dodgy ones. They can break down inside and look perfect yet still fail to give sufficient spark at full boost.
Paul
If it's still doing it I would suggest it's an ignition problem, so the first stop is to try revving the car through at low load, so try pulling away in 1st and getting to 7000rpm with no boost (say 1/4 throttle). If that's okay then remove the coilpacks and plugs as they are likely to be causing low spark strength on at least one cylinder. Check the coilpacks for signs of cracking, and that the plugs are all there (not melted) have no significant deposits and are gapped to 0.7mm. Try new plugs if you don't know the history of the current ones.
If the new plugs don't sort it, get some new coilpacks, or a few and try replacing 2 at a time to see if you can fine 1 or 2 dodgy ones. They can break down inside and look perfect yet still fail to give sufficient spark at full boost.
Paul
#6
Originally Posted by MadDogWRX
Hello.
I have a MY95 WRX with the following mods -
K&N Induction filter
XS Scoobies DP (Decat)
Afterburner Center (Decat)
Afterburner Vortex BB
VTA Dumpvalve
Run on BP Ultimate or Optimax with octane booster every tank.
The problem I am having is when accelerating hard in any gear, the car will rev freely to around 5K when it will misfire giving a sudden jerk and a loud pop + flame from the exhaust then carry on until around 6K where it sounds as if it has hit the limiter. Whilst all this is happening the boost gauge reads 0.9bar.
Is this a problem with fuelling, plugs, overboosting or detonation.
btw - Knocklink is my next mod.
Cheers for any advice
Paul
I have a MY95 WRX with the following mods -
K&N Induction filter
XS Scoobies DP (Decat)
Afterburner Center (Decat)
Afterburner Vortex BB
VTA Dumpvalve
Run on BP Ultimate or Optimax with octane booster every tank.
The problem I am having is when accelerating hard in any gear, the car will rev freely to around 5K when it will misfire giving a sudden jerk and a loud pop + flame from the exhaust then carry on until around 6K where it sounds as if it has hit the limiter. Whilst all this is happening the boost gauge reads 0.9bar.
Is this a problem with fuelling, plugs, overboosting or detonation.
btw - Knocklink is my next mod.
Cheers for any advice
Paul
I hope I've understood your question ok. If I have then it sounds like you had a similar problem to me. I added a boost valve and gradually opened it until it got to around 1.1 bar. At this stage on hard acceleration it would cut out a little like hitting the rev limiter. As I understand the ECU will only take a max boost before it cuts out under load. This is to protect it self from going bang. The only way to get round this and further increase your boost is to have the ECU chipped and remapped.
Hope this helps
#7
Hi there
I have an imported 95 WRX (My first Scooby, got her six weeks ago, quite a difference to my previous car... a roaring 1.2 Micra, the auld boxy one too )and have a similar problem but only really in first gear.
If I floor it in first, at about 4.5 to 5 thousand rpm she jerks as if I'd slammed on the brakes and then shoots off again.
However, if I give her 5 or 6 full bore standing starts, she'll pull hard and smooth after that.
This is not much use when you live in a city as doing this tends to attract a fair bit of attention!
A few other problems...
Cronic understeer in the wet... I can also get wheelspin in second if the road is wet so I am going to get new tires(needs it anyway) and get the alignment checked so hope that will fix this.
Problems starting...Always starts fine from cold, but occasionally after a short to mid journey throws a huff and won't start for about 10-15mins...engine is turning over, full tank of fuel but no joy. (I usually leave her idling for about 45secs to a min before I switch off) any ideas folks?
Not really sure what's been done to her but appears to have an HKS induction kit, a VTA dump valve judging by the scared looks on pedestrian's faces when I change gear, and an exhaust a hedgehog could happily live in.
(Sorry if this is hijacking the thread a bit but is my first post..need to get it off my chest!)
I have an imported 95 WRX (My first Scooby, got her six weeks ago, quite a difference to my previous car... a roaring 1.2 Micra, the auld boxy one too )and have a similar problem but only really in first gear.
If I floor it in first, at about 4.5 to 5 thousand rpm she jerks as if I'd slammed on the brakes and then shoots off again.
However, if I give her 5 or 6 full bore standing starts, she'll pull hard and smooth after that.
This is not much use when you live in a city as doing this tends to attract a fair bit of attention!
A few other problems...
Cronic understeer in the wet... I can also get wheelspin in second if the road is wet so I am going to get new tires(needs it anyway) and get the alignment checked so hope that will fix this.
Problems starting...Always starts fine from cold, but occasionally after a short to mid journey throws a huff and won't start for about 10-15mins...engine is turning over, full tank of fuel but no joy. (I usually leave her idling for about 45secs to a min before I switch off) any ideas folks?
Not really sure what's been done to her but appears to have an HKS induction kit, a VTA dump valve judging by the scared looks on pedestrian's faces when I change gear, and an exhaust a hedgehog could happily live in.
(Sorry if this is hijacking the thread a bit but is my first post..need to get it off my chest!)
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