Have a 99 SRX 700. Bought with about 2900 miles on it. Has run great all winter, put about 900 miles on it. Coming home from a ride on a really bumpy trail and it felt like a spark plug fouled. Stopped, popped off spark plugs, all 3 were a nice tan color, put in 3 new plugs and still ran the same, it would only go up to 50mph. Got it home, found out the center cylinder wont fire. Sled starts fine, same as it did before, but now it backfires once in while when it's running and smokes really bad. Center plug has spark, cylinder is getting gas, cleaned all 3 valves, cleaned air box, cleaned all 3 carbs, checked reeds, checked choke plunger, temp light blinks 3 times on start up, checked center pipe to make sure it hadn't collapsed; put all back together and center cylinder still wont fire. When I pop out the spark plug smoke pours out of the cylinder. Cylinder has alot of compression. Popped off the cover to the servo motor and rev engine up and the motor doesn't move at all. Would a dead servo motor cause the center cylinder not to fire, but the other two work fine? Or maybe the CDI? It just doesn't make sense.
Servo Motor Dead???
- Thread starter snowcat19
- Start date
ok, heres a few things I would check: (1.)check the wires that connect the coilpacks together, they rub sometimes on the metal bracket that holds them to the case.
(2.) do you have any friends with 98-99 srx's?, try thier coilpack and see if it works then.this is for the non firing center coil first. next step after you have fire in the hole is below.
(3.) turn down your idle under 900rpm, and watch to see if the servo motor opens, if it doesnt can you move the cables at all or are they bound up?
(4.) plug the servo motor into any other year srx, do the same under 900rpm thing, see if it moves, if it doesnt, it has 1 of the following wrong with it: (A.) the wires that run under the engine have rubbed thru and are grounding out the servo motor circuit,(5 wires to servo mtr) remove harness and repair and place in automotive conduit to solve the problem.
(B.) the cdi is defective
(2.) do you have any friends with 98-99 srx's?, try thier coilpack and see if it works then.this is for the non firing center coil first. next step after you have fire in the hole is below.
(3.) turn down your idle under 900rpm, and watch to see if the servo motor opens, if it doesnt can you move the cables at all or are they bound up?
(4.) plug the servo motor into any other year srx, do the same under 900rpm thing, see if it moves, if it doesnt, it has 1 of the following wrong with it: (A.) the wires that run under the engine have rubbed thru and are grounding out the servo motor circuit,(5 wires to servo mtr) remove harness and repair and place in automotive conduit to solve the problem.
(B.) the cdi is defective
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Doesn't sound like a servo motor problem, but you can drop the rpm's to 900 using the idle speed screw while watching the servo with the cover off. It should go to full open below 1000 rpms. This will test the servo motor, although if it doesn't work it could be a wiring or CDI problem. Is the smoke that comes out really smoke, or unburnt fuel?
Good response MrViper. I was busy typing my lame response when you replied.
Didn't you mean that if the servo motor doesn't move in the other working sled that it is likely bad?
Didn't you mean that if the servo motor doesn't move in the other working sled that it is likely bad?
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