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Multiple misfire 2003 SC Frontier (possibly related to EVAP canister/valve?)
2003 Frontier v6 Supercharged (approx. 150,000 miles on it) - here we go...
back in the Spring I started having a multiple misfire issue. First time it did it was after the truck had sat for 30min-1hr and idled rough on start-up, eventually smoothed out. Driving cross-country shortly after it did it again, engine light started flashing. Stopped for the night/misfire stopped later once the truck completely cooled down. Did it again, just once, while driving on the highway the next day. Mechanic found nothing, drove the rest of the way fine. I use premium fuel. Do regular maintenance (timing belt, pump replaced around 127,000). Code readings come up multiple misfire. I went through a full tune-up with NGK and quality parts (fuel filter, pcv valve, plugs, wires, cap and rotor - even a whole new distributor). Cleaned the MAF twice. Seafoam treatment before tune-up. I went through 5 mechanics, including the Nissan dealership. Nothing looked wrong to them. Had a pressure test done to test the fuel pump, it was fine. But I kept having random misfires, usually under the above circumstances (mostly after the truck had sat for 30min-1hr and cooled down a little). I eventually replaced the evap canister purge/vent valve under the truck. Didn't stop the issue. I then cleaned the electrical plug to the evap canister purge/vent valve and the issue stopped. I drove cross-country in May and no issue all Summer. As the weather got colder up here this last month in SE Alaska it started doing it again. Similar issue. At first, I could pull the hose on the evap canister purge/vent valve and start the truck and it would smooth out (if the engine light was on it would go off). I'd put the hose back on and continue my drive just fine. So I figured that was it, malfunctioning evap canister purge/vent valve releasing fuel vapors improperly. So I cleaned up the plug again. But then it started misfiring again while I was driving on the highway. Engine light started flashing so I pulled over and it wouldn't smooth out. Did the hose thing, didn't help. Towed it, started it the next day, and it ran fine half-a-mile even though the engine light was solid. Cooled down for about 20min, misfired again on start-up, with engine light flashing. I left it for a couple hours and went back to get it, did fine the half-a-mile back. Then started misfiring as it warmed up - engine light flashing. So I left it. Week later I started it to let it run/warm up for a bit with the cold weather and the engine light was on solid. But it was idling fine till it warmed up, then started misfiring again. (RPM needled doesn't seem to jump either). Again: Seafoam treatment (before tune-up) Full tune-up (distributer, cap, rotor, plugs, plug wires, pcv valve, fuel filter) with NGK plugs and wires New distributor Premium fuel New evap canister purge/vent valve Cleaned MAF Pressure test (A year previous there was also a smoke test done for an hour and it was fine) All fluids remain at same level (except slight leak in power steering hoses) and clean Smoke out the tail pipe is normal, no discolor and only on start-up *Slight fuel smell on start-up Code readings: multiple misfire Last edited by ACBsaun; 12-08-2016 at 12:44 PM. Reason: Adding |
#2
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The evaporative emission system won't cause a misfire. The only way it could do so is if the hose off the intake manifold that purges the vapors was leaking. It's hard to give advice without having access to scan tool data. I would want to see what the fuel trim is to see if the engine is running excessively rich or lean. See the spark patterns on an oscilloscope would be beneficial as well. If it was ignition related, I might have a look at the crank position sensor, located at the driver's side/top of the transmission bellhousing. If not ignition related, I would suspect a vacuum leak (check your hoses and intake gaskets) or dirty/bad fuel injector(s). I purchased my 2003 SVE (with the VG33ER motor) in March with almost 200,000 miles on it; it had a dead misfire caused by two faulty fuel injectors. I got a set of AUS remanufactured fuel injectors and replaced them; while I was there, I installed a new fuel pressure regulator, as well, since it was original and easy to access. The gallery-style design of the fuel injectors on the VG33 engines is not the best and tends to trap dirt on the screen of the injector. You could try a profession fuel injection service; sometimes they work, sometimes they don't.
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2003, canister or valve, canister/valve, evap, frontier, misfire, multiple, possibly, related |
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