1320VR4
08-13-2012, 01:41 PM
Okay so I've been tracking this down for months now and I'm nearing the end of my rope.
Anyhow when at cold idle, the plugs show a definite lean condition. After cruising when warm the plugs have a slight tan tint to them but it's still generally a little bit lean IMO. Occasionally (almost always when cold) the car will fall on it's face in 1st or 2nd gear, whilst in gear I let off the throttle and get back on it and it picks up fine.
Cold: On first start sometimes it will misfire so badly it stalls, if I lightly revv it a few times it will always catch and idle like a cammed muscle car at around 5-600 rpm. Whilst leaving the driveway it will sometimes fall on its face in 1st gear and 2nd (not always). For instance after shifting to second and giving it gas, it will have absolutely no power and start to bog and slow, if i let off the throttle and get back on it it'll be fine. Plugs show that it is running REALLY lean.
Warm: Drives like a normal car for the most part, plugs show a slight tanish color, but I think it's still too lean. Idles around 900 usually and holds pretty steady although the exhaust note isn't completely smooth (although the ISIS doesn't help at all). Sometimes it will drop to around 700ish and sound a little worse, usually after sitting at a red light or something for a few moments.
Checked or fixed:
Knock sensor (check engine for it, replaced and out)
IACV (cleaned out well)
TPS (checked for voltages as per that youtube video, checks good)
Coolant Temp Sensor (Replaced it today with a new unit)
o2 sensor (Replaced last week, made a HUGE improvement in warm running conditions, used to run like it did when cold when warm too)
MAF (Put in a friends car and runs fine)
EGR Temp Sensor (resistor jumped as per the write ups online, took care of check engine code for EGR)
ECU (I have several including a JWT, all ecus do the same thing except for the jwt obviously that really makes it run crappy haha)
Fuel Pressure (35psi at idle, gauge did not drop pressure when the car was off so the injectors should not be leaking, of which if they were it wouldn't be lean)
Fuel Filter (replaced)
EGR (blocked off and lines re routed per the online instructions)
Compression (I forget the exact numbers but they're almost identical to my friend's KA24 that has nearly the same numbers)
Vacuum, although I'm going to go back today and recheck for leaks since we've been fucking with stuff, the last time we checked it, there were no vacuum leaks.
Plugs (although I have not replaced these, they are the correct part number and look to be in like new condition)
Cap and Rotor (replaced)
Coil ignitor (swapped with friends car, no change)
SO. What have I NOT done yet to check? I have no check engine lights and can't figure this thing out to save my SOUL. Really getting frustrated.
help please, any idea you may have, no matter how stupid, please post away, i'll try anything at this point.
thanks,
Matt
Anyhow when at cold idle, the plugs show a definite lean condition. After cruising when warm the plugs have a slight tan tint to them but it's still generally a little bit lean IMO. Occasionally (almost always when cold) the car will fall on it's face in 1st or 2nd gear, whilst in gear I let off the throttle and get back on it and it picks up fine.
Cold: On first start sometimes it will misfire so badly it stalls, if I lightly revv it a few times it will always catch and idle like a cammed muscle car at around 5-600 rpm. Whilst leaving the driveway it will sometimes fall on its face in 1st gear and 2nd (not always). For instance after shifting to second and giving it gas, it will have absolutely no power and start to bog and slow, if i let off the throttle and get back on it it'll be fine. Plugs show that it is running REALLY lean.
Warm: Drives like a normal car for the most part, plugs show a slight tanish color, but I think it's still too lean. Idles around 900 usually and holds pretty steady although the exhaust note isn't completely smooth (although the ISIS doesn't help at all). Sometimes it will drop to around 700ish and sound a little worse, usually after sitting at a red light or something for a few moments.
Checked or fixed:
Knock sensor (check engine for it, replaced and out)
IACV (cleaned out well)
TPS (checked for voltages as per that youtube video, checks good)
Coolant Temp Sensor (Replaced it today with a new unit)
o2 sensor (Replaced last week, made a HUGE improvement in warm running conditions, used to run like it did when cold when warm too)
MAF (Put in a friends car and runs fine)
EGR Temp Sensor (resistor jumped as per the write ups online, took care of check engine code for EGR)
ECU (I have several including a JWT, all ecus do the same thing except for the jwt obviously that really makes it run crappy haha)
Fuel Pressure (35psi at idle, gauge did not drop pressure when the car was off so the injectors should not be leaking, of which if they were it wouldn't be lean)
Fuel Filter (replaced)
EGR (blocked off and lines re routed per the online instructions)
Compression (I forget the exact numbers but they're almost identical to my friend's KA24 that has nearly the same numbers)
Vacuum, although I'm going to go back today and recheck for leaks since we've been fucking with stuff, the last time we checked it, there were no vacuum leaks.
Plugs (although I have not replaced these, they are the correct part number and look to be in like new condition)
Cap and Rotor (replaced)
Coil ignitor (swapped with friends car, no change)
SO. What have I NOT done yet to check? I have no check engine lights and can't figure this thing out to save my SOUL. Really getting frustrated.
help please, any idea you may have, no matter how stupid, please post away, i'll try anything at this point.
thanks,
Matt