Coil tests good ohm check, plugs are in cylinder good compression, checking spark with old plugs and get nothing. How do I troubleshoot no spark? What else can I check? The bike ran fine in the fall but now no spark. The fuel injectors are running and getting plenty of fuel to chambers.
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Re: How to troubleshoot no spark
If fuel injectors are putting fuel into cylinders, then crankshaft position sensor is o/k as this sensor is used both for ignition timing and fuel injector timing. I would check for 12 volts at the middle pin of the connector on coil plug. If present, then ECM is more than likely at fault. You should have a low ohm reading between the center pin and either of the outer pins. As this is a single fire coil, both sides are unlikely to fail at the same time so this again points to the ECM or a common item, i.e. 12 volts supply to the coil. By the way, spark plugs will not fire if engine is turned over with no plugs fitted in engine. These engines need to see compression for spark to happen. So to check spark, leave plugs in engine and fit a new one on lead and rest it on engine while operating starter motor.
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Re: How to troubleshoot no spark
Hi Cpldake, thank you for your service, make sure you are grounding your spark plugs when checking for spark and they are new or will spark using another vehicle. Then check the ohms on plug wires. If thats ok and your coil checks out I would look towards ignition modual and ignition sensor. Also while your looking for the problem make sure you are checking all wiring and connectors for opens, shorts or grounds. Try pulling up any codes on your speedo. As a last resort consider taking it to a dealer as the electrics on this bike are very complex. Good luck
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Could be an ignition module. Check the coil first.
Check your pick-up sensor located inside the timing cover, behind the adjustor plate. If the filament is not intact you will have no spark.
A defective coil, cam position sensor, or stator will also cause a no spark condition.
First check for diagnostic trouble codes (DTCs). THEN check the condition of the battery and do a voltage test
and recharge the battery if it is below 12.60V. THEN check the condition and tightness of the battery connections
and perform either a conductance test or a load test and replace the battery if and as necessary. THEN remove the spark plug cable from one of the spark plugs and remove the plug and visually check the condition of the plug. THEN attach the HT cable to a SPARK TESTER and clip the tester to the cylinder head bolt and crank the engine over looking for spark and repeat the procedure on the other cylinder also. Be aware that the Engine will not spark with both spark plugs removed, so when checking for spark, use a SPARK TESTER with both plugs installed.
Ignition Coil Primary Circuit Test
Remove the coil. THEN set your ohmmeter scale to RX1 and place ohmmeter leads on the primary coil windings A (front of coil) to B (middle of coil), B to C (front of coil) and check for primary coil winding resistance which normal resistance range is 0.5-0.7 ohms. If primary resistance is not within this range check out test results below.
Ignition Coil Secondary Circuit Test
With the ignition coil removed from the motorcycle and the ohmmeter set to the RX1K scale place the ohmmeter leads on the secondary coil windings B (middle terminal) to
R (rear secondary terminal/socket), B to F (front secondary terminal/socket) and check for secondary coil winding resistance which normal resistance range will be 5.5-7.5K ohms. If secondary resistance is not within this range check out test results below.
A low resistance value indicates a short in the coil winding which requires coil replacement.
A high resistance value might indicate that there is some corrosion/oxidation of the coil terminals requiring the coil terminals to be cleaned and the resistance test then repeated and if after the test is repeated the resistance is still high after the terminals were cleaned the coil must be replaced.
If there is an infinite ohms or no continuity) resistance value the coil is open and must be replaced.
Hi Richard, I'm glad to help! Richard, there's a lot of things that can cause one certain cylinder to misfire. I would first: "Replace the Spark Plug and Spark Plug Wire for number 4 and see if the misfire goes away. If it doesn't then you need to do a "Compression Test" for cylinder # 4 and compare it to another cylinder and if its more then 25 Psi difference then you need to do a "Cylinder Leak Down Test" to see where you are loosing the compression. If the compression is good and you have new plug and wire and it still misfires. Then you'll need to check and make sure you have good spark coming from the coil. If you have good spark coming from the coil. Then you'll need to check and make sure the # 4 Injector is firing. Hope this helps and have an awesome day Richard.
Carb or fuel injection? Spark or no spark? Check for spark by putting a new plug into lead and laying on cylinder head. Leave old plug in engine. Start bike. If carb and no spark then plug or coil would be first suspects, then ignition module, then wiring from coil to ignition module. This is assuming you have compression on rear cylinder and all mechanical checks completed. If fuel injection and good spark, then ECU most common problem. Then injector, then wiring. If no spark, check coil, then wiring frpm coil to ECU, then ECU.
It could be couple problems: -Misfire. (Include bad injector, Coil, spark plug wire) -Lost compression due to broken valves, cylinder wall and head or gasket.
Solution: 1 -Do compression test. - If not with in specification (Too low) Need rebuild engine due to broken valve, blow out gasket or even broken cylinder wall. -All cylinder has good compression: Now need to check Spark plug, wire and all injector. Injector must be with in specification (In Ohm) Follow its manual.
G,day. If only the L/H front cylinder is the problem & compression is good then the most likely possable causes of your problem are - A open circuit spark plug cap on that cylinder or a carburettor fault(blocked jet) on that cylinder(or carby balance setting).I would suggest testing the ignition coil secondary resistance.Do this by removing plug caps from cylinders 1 & 4. Set multimeter to kilo ohms(ohms x 1000) .One test lead to one plug cap- other test lead to other plug cap(do not allow probes to touch your fingers-touching both test probes whilst undertaking this test will give a false reading).reading should be 10 to 20kilo ohms.If open circuit-remove plug caps from leads( they unscrew)and test caps seperate. Should read 5 kilo ohms. Replace if open circuited(This is a common problem on all road bikes).If that sounds to difficult, any good motorcycle shop should be able to check them while you wait.It only takes a few seconds.Sorting the carbies without experience is very tricky.Have the carby balance & mixtures checked first in case its just an incorrect setting before pulling off & cleaning the carbies. Hope this is helpfull Regards Andrew Porrelli
test the spark plug wire for ohms resistance, inspect the spark plug, test the coil for ohms resistance. run a compression test to see if it is the cylinder lost compression (valve job - cracked head or blown gasket) Best regards Ck
first do a cylinder compression test on engine to verify good engine compression this should be around 110psi to 175 psi check for vacuum leak, intake port for #6 cylindermay be leaking air, or also check coil for that cylinder, if wire and spark plug have already been changed, last replace fuel injector for that cylinder.
Could only be a few things. The coil #1, Fuel injector #1, Stuck intake or exhaust valve, or blown head gasket allowing coolant into cylinder #1. Use a spark tester to check the spark coming out of cylindr #1 if checks good then ohm test the injector when it is warm. Check other injectors to compare. Do a compression test on cylinder #1 and test other cylinders to compare. If cylinder is low compression suspect valves and or head gasket. If compression is low then het a leak down tester to test if a valve is broke or sticking. On your sable i would suspect injector or coil most likely.
You said compression is good then i would say you may have a bad coil , unless one coil runs all cylinders, but could still be a coil,,next thing i would check would be the injector make sure it gets a pulse if it does then try switching injectors from that cylinder to another cylinder and see if the weak cylinder changes with the injector change, if it does then you have a bad injector,