Power FC Running either very lean or very rich at transition from vac to boost, Help?
Running either very lean or very rich at transition from vac to boost, Help?
My car has been running like a top for the last 3 years, two weeks ago I noticed a lean feeling for a brief moment when getting on it around a corner (not fuel slosh, had a full tank) It seemed to be alright after that, made a good 1st-4th pull with out any issues and normal knock
Since then however it has been getting progressively worse to the point when i transition from vac to boost I'm now running on one rotor. Almost feels like when my secondaries kick in one is dumping fuel? Once i come off the throttle (not right off but back to a cruise input) it will continue to run on one rotor for 2-3 seconds and then smooth out and run normal. I'm not entering any more then 1-2 psi as I'm concerned about popping it.
When looking at my wideband when it runs on one rotor it will go to 10.X and then up to 16.X-17 afr. fuel pressure is rising up to 3.0 bar which is regular and my knock isn't going above 12 (that's always been normal for the car, I usually see 16-17 on a hard pull.)
The Map hasn't been altered other then leaning out my Idle a little bit about a month ago. I'm running stock primaries and 1300 secondaries with a fjo, also on the ignition side I have a hks twin power. It's a single 35r with a mild street port.
Plugs were changed about 10000 kms ago and wires and fuel filter are about 3 years old with about 25000. Always run on 94 octane with a syn. premix.
I think I have given all the important info that I have. Hope someone else has gone through this and has somewhere for me to look at.
Cheers
Andrew
Since then however it has been getting progressively worse to the point when i transition from vac to boost I'm now running on one rotor. Almost feels like when my secondaries kick in one is dumping fuel? Once i come off the throttle (not right off but back to a cruise input) it will continue to run on one rotor for 2-3 seconds and then smooth out and run normal. I'm not entering any more then 1-2 psi as I'm concerned about popping it.
When looking at my wideband when it runs on one rotor it will go to 10.X and then up to 16.X-17 afr. fuel pressure is rising up to 3.0 bar which is regular and my knock isn't going above 12 (that's always been normal for the car, I usually see 16-17 on a hard pull.)
The Map hasn't been altered other then leaning out my Idle a little bit about a month ago. I'm running stock primaries and 1300 secondaries with a fjo, also on the ignition side I have a hks twin power. It's a single 35r with a mild street port.
Plugs were changed about 10000 kms ago and wires and fuel filter are about 3 years old with about 25000. Always run on 94 octane with a syn. premix.
I think I have given all the important info that I have. Hope someone else has gone through this and has somewhere for me to look at.
Cheers
Andrew
10,000k on plugs is way too long. I use two sets of R7420-9/10 that I swap out/clean/regap about every 2000km. No this is not causing your problem, but it can affect your performance.
It would not hurt to verify you in-tank fuel filter is clean and not clogged with dirt from a bad batch of fuel.
Your pump could be going bad or internal tank fittings. I am on my third pump as they started loosing pressure with age.
Check you fuel pressure when on boost.
It would not hurt to verify you in-tank fuel filter is clean and not clogged with dirt from a bad batch of fuel.
Your pump could be going bad or internal tank fittings. I am on my third pump as they started loosing pressure with age.
Check you fuel pressure when on boost.
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