For those of you who can't remember the contents of that earlier thread, let me give you a very brief overview:
My car is experiencing what I perceive to be detonation when accellerating very lightly at speeds of 40-70 mph and between 2500-3500rpm. A previous ECU diagnostic showed a code 34: detonation sensor circuit fault. The car started doing this approximately 2 months after I bought it and only does it when the engine is thoroughly warmed up. I recently switched to a JWT chip and JWT cone air filter and the problem remained constant.
Today's ECU diagnostic (Mode II) showed the expected code 34 but also a code 33: exhaust gas sensor circuit (left). Putting the diagnostic into Mode II - heated oxygen sensor monitor - resulted in a clean result (i.e., no problems reported for either left or right side). Documentation provided on ttzd.com state that a code 33 would cause the "check engine" light to come on under normal (Mode I) operating conditions. However, this is not the case. I have read on this forum somewhere that exhaust gas sensors going bad can do so slowly and not cause the check engine light to come on.
So, code 34 we know about. I either get a new detonation sensor (which is a pain in the *rse to replace)or bypass it following ZViking's (I think it was him) procedures - not without risks. It would not seem that my car is running in safety boost mode at all and I'm not running any increased boost at the moment (over stock) as I haven't yet installed the boost jets to compliment the JWT chip I have installed. Question: could the knock sensor (aka detonation sensor) influence the ECU to change timing between 2500-3500rpm but not put it into safety boost mode? Note: my ignition timing is correctly set at 15 degrees BTDC.
Code 33 indicates that the left exhaust gas sensor (I take it this is one of two "Lambda sensors"?) is going dodgy. Where can I find these two sensors (both left and right) and can they be easily exchanged and does anyone know how much Nelson charges for the parts?
I reckon that I'm slowly going to replace sensors etc to find the cause of this detonation problem by method of elimination.
Further to the above, in discussions with some of you the concept of a "sticky injector" has come up several times as well as a problem with the fuel damper/regulator. Can someone please shed some light on these two issues and recommend a way to eliminate these parts as the cause of my problems. Can I replace the fuel damper/regulator easily and how much will it cost me?
Right, I think I'll quit here - there is an awful lot of text already . Thanks in advance to all of you who will share your wisdom with me.
Take care,
Danny
PS - I also ran a transmission diagnostic which came up completely clean. Am now going to look into changing all the A/T fluid for peace of mind.
[This message has been edited by Danny (edited 22-01-2002).]
Hey guys,
Following on from a post I placed in late December ( http://www.300zx.co.uk/forums/ubbforum/Forum1/HTML/004638.html ) with regards to a detonation problem that I was having, I have finally today found the time to perform a full ECU diagnostic.
For those of you who can't remember the contents of that earlier thread, let me give you a very brief overview:
My car is experiencing what I perceive to be detonation when accellerating very lightly at speeds of 40-70 mph and between 2500-3500rpm. A previous ECU diagnostic showed a code 34: detonation sensor circuit fault. The car started doing this approximately 2 months after I bought it and only does it when the engine is thoroughly warmed up. I recently switched to a JWT chip and JWT cone air filter and the problem remained constant.
Today's ECU diagnostic (Mode II) showed the expected code 34 but also a code 33: exhaust gas sensor circuit (left). Putting the diagnostic into Mode II - heated oxygen sensor monitor - resulted in a clean result (i.e., no problems reported for either left or right side). Documentation provided on ttzd.com state that a code 33 would cause the "check engine" light to come on under normal (Mode I) operating conditions. However, this is not the case. I have read on this forum somewhere that exhaust gas sensors going bad can do so slowly and not cause the check engine light to come on.
So, code 34 we know about. I either get a new detonation sensor (which is a pain in the *rse to replace)or bypass it following ZViking's (I think it was him) procedures - not without risks. It would not seem that my car is running in safety boost mode at all and I'm not running any increased boost at the moment (over stock) as I haven't yet installed the boost jets to compliment the JWT chip I have installed. Question: could the knock sensor (aka detonation sensor) influence the ECU to change timing between 2500-3500rpm but not put it into safety boost mode? Note: my ignition timing is correctly set at 15 degrees BTDC.
Code 33 indicates that the left exhaust gas sensor (I take it this is one of two "Lambda sensors"?) is going dodgy. Where can I find these two sensors (both left and right) and can they be easily exchanged and does anyone know how much Nelson charges for the parts?
I reckon that I'm slowly going to replace sensors etc to find the cause of this detonation problem by method of elimination.
Further to the above, in discussions with some of you the concept of a "sticky injector" has come up several times as well as a problem with the fuel damper/regulator. Can someone please shed some light on these two issues and recommend a way to eliminate these parts as the cause of my problems. Can I replace the fuel damper/regulator easily and how much will it cost me?
Right, I think I'll quit here - there is an awful lot of text already
. Thanks in advance to all of you who will share your wisdom with me.
Take care,
Danny
PS - I also ran a transmission diagnostic which came up completely clean. Am now going to look into changing all the A/T fluid for peace of mind.
[This message has been edited by Danny (edited 22-01-2002).]