redtop 3sge woe's Options

[rdyzz]

the long

so my engine has been running like its on two maps or somthing. it started doing this after the last track event in july, i've been trying different things on it since then. its a redtop 3sge im wondering if anyone has ever had an engine of theirs do this. i feel like im chasing a ghost since every time i think i make break through it seems to come back. first diagnosis was on a dyno, testing for air fuel ratio, in 4th gear at wot around 2,000-4,000rpm the air fuel was in the 17's and then got to about 11.9 at redline. lowering the spark plug gap to 1.0mm seemed to have made a difference there. i then installed a fuel pump after and it seemed to drive well for the most part, i then replaced the fuel filter a week after the new walbro 190 pump. did an on car injector clean with an on car cleaner kit. the car still occasionally hesitates in 2nd gear or 3rd gear at 1/4 throttle if i was to give it quicker throttle inputs. at the moment i got more parts comming, COPS and a new vvti cam pulley. i just dont understand why an engine would do this, you can feel the difference in throttle response.


the short

symptoms. intermittent hesitation 1/4 throttle, or quick throttle inputs. drives like it has power, then drives like it lacks engine torque at times. certain times WOT in 1st from a roll will be super powerful you have to hold onto the steering wheel to keep car straight, other times same 1st gear roll will feel less powerful by quite a bit.

what i have done.
- fuel pump, walbro 190
- new fuel filter
- adjustable fuel pressure regulator set at 43psi
- new tps sensor
- tested with new water temp sensor
- tested 1mzfe maf, swapped maf, 1mzfe car still ran fine
- checked most connectors and repaired any cracks in insulation
- new 2 ga ground cable
- cleaned fuel injector with on car injector cleaning kit
- seafoam oil, ran in fuel tank also
- o2 sensor is 1 year old
- new spark plugs
- inspected vvti solenoid, its clean and functions
- checked for vacuum leaks

what i have not tried yet.
- new COP
- new vvti pulley
- knock sensor
- new ecu

i dont know if the cam angle or crank angle sensor has anything to do with this. it doesnt have any symptoms related to these two.

thanks for any insight.

[richee3]

Nice, that explains it. I keep a tab open in my phone for 6gc, my350z, and the BEAMS Owners Group. Never really bother to navigate the rest of mr2.com.