Missing at speed

[seaox230c]

I installed the cleaned and tested fuel injectors...sandpapered all the grounds down to block metal-reinstalled my fuel pressure gauge that is in line between the fuel rail and the regulator...36-37 psi all times..and the motor stil. I am ready to ask suzuki WHY I would ever buy another one

[seaox230c]

Since I found out my dealer/mechanic was of no use to me I made a set of breakout harness wires to read the computer/components while i was running the engine and having problems. I made a set of jumpers so I could read the output of the pulser coils and the timing coil when I was having my issues. The voltage outputs of the coils all seem ok...but the frequency (HZ) of number 1 pulser seem way out of synch with number 2 and 3 . The manual calls them pulser coils but the parts catalog lists them as ignition timing coils...if one of them reads 50% and plus higher for any given rpm....who knows what that does to the spark...and thus my problem of broken up spark above 3200 rpm on cyl bank 2-4-6

[seaox230c]

During t/s I found the brown wire at my smartgauge not connected to anything..this is the signal in from the oil flow sensor
HA_HA_HA...that would have been too simple. I connected the pink wire to the brown wire on my smartgauge...disconnected the oil sensor and jumpered the two harness wires..the oil light and buzzer come on...reconnected the sensor and went for a ride. At 3500 rpm the motor misses and stumbles..no oil light or buzzer...disconnected the sensor totally and the motor still misses at 3500...the endless troubleshooting adventure

[seaox230c]

Still no Joy...I built a breakout harness to read the output of my low and high charge coils in the stator while the engine was running. The low charge coil (Green wire and Black/red wire) put out 30v ac rms at 1000 engine rpm and had a HZ of approx 100 HZ . It went up to 35v and 190 HZ at engine rpm of 2000. It showed 33.5 v and 290 Hz at 3000 engine rpm and at engine miss speed of 3200-3300 it still showed 33.v and the 10ths would flutter a little. If I crossed these 2 wires out...the engine would run perfectly normal to about 3000 and then would flutter a couple of hundred rpm
My high charge coil (White/red and White /blue ) showed 130vac rms and 100 HZ at engine speed of 1000rpm..the volts would go up a little as the coil / engine warmed up I would be a little over 140v at same speed on the way back about an hour later. At 2000 rpm the volts were still 130 and my HZ matched the low coil at 190. Something odd happened as I further increased speed....At 3000 rpm my volts had dropped to 90v ac rms even though the output freq evenly matched the low coil at 290 and when I took the engine to miss speed at 3300 rpm my volts would drop down to the upper 80's and would flutter 2 or 3 volts as the engine would increase/decrease rpm
I would have expected my output voltage to increase or at least remain somewhat constant as I increased rpm...I was not expecting them to drop 50v as speed picked up...unless this is what happens when you increase the frequency...the overall voltage drops because I am exciting the coil for shorter time periods..don't know
Another thing when I took the meter leads out of the meter and crossed them like I did for the low coil...the engine dies instantly...no matter what speed I was running..where as the low coil would do nothing when crossed below 3000 rpm

The resistances of both coils were ballpark ...70 ohm for the low when hot and 655 for the high when hot..I cannot read the resistances of the coils when they are active...only with the engine off.

I was expecting something a little more dramatic like a totally open coil or a voltage to drop to 0 when the engine started to act up. The high coil dropping voltage fro 130v at 1000 to 88v at 3300 may be my issue, but it was always a smooth drop never erattic. I'd like to have some confirmation before buying a stator coil

[redlowrey]

I still think the ecu is shutting down the cylinders, just make sure the neutral switch in gear signal stays the same when the hrottle is pushed all the way,

[seaox230c]

Where is this switch...I have seen photos with a switch at the gearshift linkage at the bottom of engine..mine does not have this switch..at least in that location..thanks

[seaox230c]

I have to go back and retest the capacitor charge coils..the resistance is checked through the coils obviously..green to Black/red and White/red to
White/blue.....I also measured voltages through these same wires...the book for some reason has me cheking the green wire to ground for voltage output...the black/red to ground...the white/red to ground and so forth...like the voltage runs both ways thru the coil...I will recheck on tuesday and see if my outputs are markedly different

[seaox230c]

Having some ignition issues with my 2003 DT225..after exhaustive testing yesterday I am down to coil number 2 misfires exactly in sequence with the engine missing at around 3200-3500 rpm. Coils 4 and 6 also break up a little but not in synch with the engine missing AND when #2 goes bad for several seconds...4 and 6 fire steady 2-4-6 are the same bank. 1-3-5 all spark steady no matter what. I swapped 1 and 2 coil-no difference 2 still misses. Please reference the schmatic below of the CDI unit..Its a factory new. My Condenser charge coils -high and low are 2 independant coils built into the stator . My low condenser charge coil ..the upper one has a Green wire and a Black/Red off each end of the coil It appears the G leg feeds capacitor C1 which powers coils 1-3-5 and the Black/Red wire feeds cap 2 which powers coils 2-4-6 The High condenser charge coil is the lower one and has a White/Blue wire that feeds C1...coils 1-3-5 and the White/Red wire feeds C2 coils 2-4-6 ...so the low and high charge coils each feed both capacitors. The resistance of each condenser charge coil is approx textbook value but the output voltages are low for each wire to ground. The manual has me checking coil output by green to ground...black/red to ground...white/bl to ground and white/rd to ground instead of checking the voltage across the whole coil..green to black/red and the white/blue to white/red. Each low coil wire to ground reads approx 30v ac at all engine speeds..the book calls for approx 80 at speed. The high wires read about 135-140 vac at 1000 rpm but drop to around 75vac at 3000 rpm the White/red leg reads about 10v lower than White/blue at 3500 rpm when the engine misses. The book calls for something like 200v at speed from my high coil. How can 2 independant coils be so off from textbook voltages and still run perfect at 3000 rpm but fails at 3300 with only a little less voltage drop.

What I want to do is criss cross the outputs of each coil so the low coil G wire output feeds the Black/red input and have the Black/red output feeds the G input. Basically I can move the connector wires so G feeds cap2 bank 2-4-6 and Black/red feeds cap 1 1-3-5 and do the same for the high coil so white /red now feeds cap 1 and White/bl feeds 2-4-6. That would be opposite power sources as compared to the print.

From the diagram it appears that the system would never no the difference but if bank 1-3-5 now starts to miss I know its a problem in my stator charge coils

Will this work without doing any damage

[seaox230c]

Finally..light at the end of the tunnel...I swapped polarity on both low and high condenser charge coils and my issue swapped to #3 coil blanking out at 3300 rpm...2-4-6 remained stable so it appears my problem is with my condenser charge coils in the stator...will order one tomorrow

[seaox230c]

Yee-Haaa...put in the new stator today...made 5200 rpm...no issues so it was the high charge coil in the stator going bad all along...long time getting here but i'm glad its fixed...suzuki manuals suck...will run the stator charge coil test next week to see the difference between the old stator and the new one