Had plugs changed on my 1990 62 recently (along with new exhaust). What came out we’re not stock plugs bpr5es-11 (gap is wider than FSM) put in by PO. Replaced with Denso W16EXR-U stock ones. But I developed a very very slight bouncing / low idle and I think tiny misfire. I can hear the tiny misfire out exhaust. (Video Attached)
To rule out the plug gap, I switched in NGK BPR5EY-11... didn’t help, now back to running stock NGK BPR5EY. Still has the ever so slight bounce idle / and I think misfire. I did reset ECU and have run enough miles through it.
I tried searching for a vacuum leak using brake cleaner but didn’t find one.
Am I being anal or is this idle a bit rough and there’s a misfire that should be solved or ignored.
Link to Video:
Link to FJ62 idle bounce / misfire.
UPDATE1
- Found some slight sparking going on on the spark plug wires in the dark. Replaced with OEM wires. (Gonna confirm tonight that there’s no arching anywhere else)
- disconnected battery / reset ecu
- everything is working but the bouncing idle and slight miss is still there.
- still figuring it out...
UPDATE2
- replaced my fuel filter because it hadn’t been replaced since I owned the vehicle.
- looks like the old one on there was for an fj80
- no change in my idle issue
UPDATE3
- pulled off the black ISVC and cleaned the plunger.
- replaces fuel pulsation dampener
- no change. Still slight misfire / bouncing low idle.
UPDATE3
- mechanic replaced:
- 02 sensors
- distributor cap
- set timing
- improved slightly but still noticeable especially once warm and idle drops. Still slight misfire / bouncing low idle.
(I may try the fuel pressure regulator at some point in future as @slcfj62 had mentioned in one of his posts that this in conjunction with the dampener and fuel filter fixed all hi rough idling issues. As of now I’m just living with it.)
To rule out the plug gap, I switched in NGK BPR5EY-11... didn’t help, now back to running stock NGK BPR5EY. Still has the ever so slight bounce idle / and I think misfire. I did reset ECU and have run enough miles through it.
I tried searching for a vacuum leak using brake cleaner but didn’t find one.
Am I being anal or is this idle a bit rough and there’s a misfire that should be solved or ignored.
Link to Video:
Link to FJ62 idle bounce / misfire.
UPDATE1
- Found some slight sparking going on on the spark plug wires in the dark. Replaced with OEM wires. (Gonna confirm tonight that there’s no arching anywhere else)
- disconnected battery / reset ecu
- everything is working but the bouncing idle and slight miss is still there.
- still figuring it out...
UPDATE2
- replaced my fuel filter because it hadn’t been replaced since I owned the vehicle.
- looks like the old one on there was for an fj80
- no change in my idle issue
UPDATE3
- pulled off the black ISVC and cleaned the plunger.
- replaces fuel pulsation dampener
- no change. Still slight misfire / bouncing low idle.
UPDATE3
- mechanic replaced:
- 02 sensors
- distributor cap
- set timing
- improved slightly but still noticeable especially once warm and idle drops. Still slight misfire / bouncing low idle.
(I may try the fuel pressure regulator at some point in future as @slcfj62 had mentioned in one of his posts that this in conjunction with the dampener and fuel filter fixed all hi rough idling issues. As of now I’m just living with it.)
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