No codes. I dont really know what to think at this point. Thats why im asking here. It is my hope that someone will see this and say....Yea mine was doing that and it was........... Thanks Tony
I understand, Tony. But there usually isn't just one thing. The ECM is pretty good at telling you if there is a bad sensor. They all have signal too Hi/Lo fault codes.
So, Here’s your To Do List. Fuel, Air, and Spark. There are a number of things to check. All can be done in one day and relatively inexpensive.
Fuel:
- As was said, bad fuel can happen anytime. Or, weird weather that results in condensation in the tank. Is this old fuel that’s been in there since last fall? You may have to siphon out the tank and refill. Be sure to get the hose all the way to the bottom. That’s where the water is.
- There are dozens, maybe hundreds of posts on here over the years attesting to, that the 998 needs the occasional dose of Seafoam. Get some in the tank and run it. If, after a few minutes it begins to improve, keep it running and try to ride it up and down the driveway and around the block. Stay close to home.
- How old is the fuel filter? How many miles? The one that’s on there could be 10 years in service. Right side by where the canister used to be. You already know where it is. Replace. Piece of cake.
Air - Not Enough:
- It’s spring. Critters are on the move, building nests, and procreating. Open up your intake at the air filter and check things out…including the condition of the air filter.
Air - Too Much:
- Back to vacuum leaks. I see by your profile that you have an SM5. Then, you have another vacuum system over there on the right-hand side of the machine that provides the vacuum assist for the clutch. It starts at the throttle body for the front cylinder, goes through a check valve, to the solenoid valve and then down to the clutch. Inspect the length of hose for cracks and holes. Make sure that it is still connected to the throttle body. You will notice that the solenoid valve has an open port. That is to relieve the vacuum from the clutch when you release the clutch handle. It should NOT be sucking air all of the time. If it is, replace. Refer to pic.
- Also, another source of vacuum leaks is the rubber boot that the throttle bodies mount into with the rest of the engine. You’ll see those hose clamps and rubber boots. Check for tightness of the clamps and inspect the rubber boots for cracks and leakage. There are those that have tried an in-place repair with silicon sealant. Doesn’t work. A full replacement is called for.
Spark:
- While you’re crawling around in there, check out those wires that you put on to see if there’s a rub that damaged the insulation, and that you put them on the plugs completely.
Heat under the bodywork is the enemy of the 998’s rubber components.
By the way folks - It’s not a PCV valve. It is a Purge valve. Two completely different emission control systems. Neither the 998 nor the 1330 have PCV valves, only Purge valves.
