erknjerk78

iTrader: (1)

hey club lex fam! although i've been a member since '09, this is my first post.

here's the deal...i just picked up a 2000 gs400 with an rmm supercharger kit, split sec fuel/timing calibrator, and possibly a tc (seller was told it had one, but didn't confirm) last saturday. my vsc light stays on 24/7 regardless if it is engaged or not. my cel light was on 24/7 till the seller disabled the actual light. the car is constantly running rich (at least that's what the air/fuel meter reads) and feels like it hits the rev limiter at 5k rpm. the rev limiter thing doesn't happen all the time, but enough to make me wonder what's wrong. today, i decided to run an obd2 scan and it kicked 16 codes...

P0300 - Random/Multiple Cylinder Misfire Detected
P0301 - Cylinder 1 Misfire Detected
P0302 - Cylinder 2 Misfire Detected
P0303 - Cylinder 3 Misfire Detected
P0304 - Cylinder 4 Misfire Detected
P0305 - Cylinder 5 Misfire Detected
P0306 - Cylinder 6 Misfire Detected
P0307 - Cylinder 7 Misfire Detected
P0308 - Cylinder 8 Misfire Detected
P0340 - Camshaft Position Sensor Circuit Malfunction
P0420 (x2) - Catalyst System Efficiency Below Threshold (Bank 1)
P0430 (x2) - Catalyst System Efficiency Below Threshold (Bank 2)
P0715 - Input/Turbine Speed Sensor Circuit Malfunction
P1350 - not sure

any info will be much appreciated! thanks in advance!

kdick91

Well, first off, don't do more work than you have to and go ahead and remove the blower from the TB, slap on a stock airbox with MAF and run diagnostics with a stock tune. That will make your life far easier since you don't know what the tune is doing.

Let's start down this list with what I think may be your issue.

P0300-P0308 - I believe this is related to your P1350 and P0340. Possibly P0715.
P0340 - Something is wrong with your crankshaft position sensor. It can be one of three things. The sensor is done (which happens), the wiring between the sensor and PCM is frayed/gone, or the orientation between the sensor and crank has changed. The third situation is difficult to explain and isn't very common, but I have had it happen to me before in which case a crankshaft position relearn will fix it. Almost any dealer can do it for a couple bucks.
P0420 & P0430 - I'm pretty sure the previous guy removed the catalytic converter. A quick crawl under the car will confirm. If it appears they are there, tap on them with something hard. SOFTLY. It will either sound hollow or full. If it sounds full, it is possible that it has been running rich for so long that it has clogged the cats (they burn unburt fuel amongst other things)
P0715 - This is just a speed sensor malfunction, so the diagnostics would be similar to that of the crankshaft sensor. Depending on the car, sometimes this can be tripped by the crankshaft sensor not working (really depends on the nature of the car and whether or not different parameters IE:shift points are set by RPM or speed)
P1350 - This is caused by a malfunction within the ignition control unit. If memory serves me, the ignition control unit is a small metal box on top of the driver side fender. If the car is having trouble knowing which cylinder is firing, it will detect misfire.

If I were you, I would get the crank sensor changed, do a rest and see what codes exist. If you still have a bunch, chase down the P1350 and I bet you all of your misfire codes will disappear. It doesn't look like you have too hard of a project, but you need to really figure out what you are working with as far as that supercharger goes. You never know what some people do when installing kits like those.... Good luck on it though! And enjoy your ride!

Kyle