brage
08-03-2003, 10:51 AM
The following is referring to a 1996 KA24DE in a 1995 S14 240SX.
Just looking to get some quick opinions on the most likely cause of a power loss above 4000 RPMS...
Here are the symptoms:
When under load the car will accelerate normally to about 4,000 rpm, after 4000RPM the car just seems unresponsive if I go WOT it almost feels like it is hitting the rev limiter. Also, starting at 4,000 RPM the engine starts to get very loud and sounds "cammy". This sound is only heard under load. When the engine is revved in neutral it sounds normal.
The fuel injectors are from my old motor which had approximately 106,000 miles on it. Everything else came with this engine and has ~60,000 miles on it.
The problems came up after I tested the compression and installed new spark plugs. The compressesion checked out at ~195psi on all 4 cylinders. The timing is set at 17 degrees BTDC.
After I started experiencing this problem, I thought I would try checking the compression again and switching back to the originial plugs (I had switched from OEM to Bosch platinum +4s).
The compression once again checked out at 195psi on all four cylinders. After the orginal spark plugs were installed, the problem did not dissapate.
Looking for some insight, information on where I should start debugging this problem, perhaps whether I should bring it to a mechanic, although I haven't found a mechanic around here i trust. I was just about to install the F-Max stage II turbo kit on this car and I need to get this resolved first.
I have new injectors, MAF, ECU that will be going into the car along with a new walbro 255lph HP fuel pump w/ S14 compatible sock. The turbo kit is sitting in my garage awaiting the resolution of this problem :(
Just looking to get some quick opinions on the most likely cause of a power loss above 4000 RPMS...
Here are the symptoms:
When under load the car will accelerate normally to about 4,000 rpm, after 4000RPM the car just seems unresponsive if I go WOT it almost feels like it is hitting the rev limiter. Also, starting at 4,000 RPM the engine starts to get very loud and sounds "cammy". This sound is only heard under load. When the engine is revved in neutral it sounds normal.
The fuel injectors are from my old motor which had approximately 106,000 miles on it. Everything else came with this engine and has ~60,000 miles on it.
The problems came up after I tested the compression and installed new spark plugs. The compressesion checked out at ~195psi on all 4 cylinders. The timing is set at 17 degrees BTDC.
After I started experiencing this problem, I thought I would try checking the compression again and switching back to the originial plugs (I had switched from OEM to Bosch platinum +4s).
The compression once again checked out at 195psi on all four cylinders. After the orginal spark plugs were installed, the problem did not dissapate.
Looking for some insight, information on where I should start debugging this problem, perhaps whether I should bring it to a mechanic, although I haven't found a mechanic around here i trust. I was just about to install the F-Max stage II turbo kit on this car and I need to get this resolved first.
I have new injectors, MAF, ECU that will be going into the car along with a new walbro 255lph HP fuel pump w/ S14 compatible sock. The turbo kit is sitting in my garage awaiting the resolution of this problem :(