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Re: lack of power, slooow to boost- intermittent
Posted: Mon Jun 01, 2015 4:25 pm
by susiemk
It may sound pretty stupid but
Do you have good Vacuum values (18-20 in park / N)?
Is compression good on all cyl?
Ive seen a never ending lean condition on a car with low compression on 1 cyl
Have you checked the knock sensor for cracks in the plastic?
This will give you false knock readings & pull times whenever its feels like it?
If knock sensor is OK have tried to run the car with a knock sensor (a spare sensor is best) plugged into the harness but not bolted to the block (zip-tie it securely to a hose or something soft) ?
This can help to eliminate the k-sensor as the cause of your problem
Is the wiring of your 02 sensor OK - pins fully terminated & engagement points nice & tight?
Re: lack of power, slooow to boost- intermittent
Posted: Mon Jun 01, 2015 5:11 pm
by Legacy777
You could try disconnecting the plug to the O2 sensor and see if that changes anything. I don't think you can really "clean" an O2 sensor.
Regarding the filter and MAF, did you have problems before you changed the intake setup? If not, try going back to what you had previously.
Re: lack of power, slooow to boost- intermittent
Posted: Mon Jun 01, 2015 5:23 pm
by bcmaxx
susiemk wrote:It may sound pretty stupid but
Do you have good Vacuum values (18-20 in park / N)?
Is compression good on all cyl?
Ive seen a never ending lean condition on a car with low compression on 1 cyl
Have you checked the knock sensor for cracks in the plastic?
This will give you false knock readings & pull times whenever its feels like it?
If knock sensor is OK have tried to run the car with a knock sensor (a spare sensor is best) plugged into the harness but not bolted to the block (zip-tie it securely to a hose or something soft) ?
This can help to eliminate the k-sensor as the cause of your problem
Thanks for the suggestions. All vacuum lines new. Compression is great. No vacuum leaks. Its between 19-20 in park. Knock senor oem subaru brand new properly torqued. I have a spare i can plug in and try!
Is the wiring of your 02 sensor OK - pins fully terminated & engagement points nice & tight?
Re: lack of power, slooow to boost- intermittent
Posted: Mon Jun 01, 2015 5:25 pm
by bcmaxx
Legacy777 wrote:You could try disconnecting the plug to the O2 sensor and see if that changes anything. I don't think you can really "clean" an O2 sensor.
Regarding the filter and MAF, did you have problems before you changed the intake setup? If not, try going back to what you had previously.
I only had a similar problem when the old engine was puking oil into the intake and contaminating the maf and intercooler. I think ill unplug the 02 and go for a drive. Then return the intake to normal ill post up my findings
Re: lack of power, slooow to boost- intermittent
Posted: Tue Jun 02, 2015 7:50 pm
by bcmaxx
so I'm feeling like an idiot, it may have been my aem trueboost spring open settings causing, boost spike and oscillation ( quicker than i would see on the gauge) I have set it to zero and so far so good, I'm going to drive it all week and report back if that was in fact the problem all along. not too sure why it would be intermittent, ill be isolating the tru boost to confirm, just run of wastegate spring in the mean time