rpg51

Did you notice if the valve gaps tight before your adjustment?

I can't tell from the pictures whether the retainers are showing any signs of cracking. The cracks generally appear on the underside. From the topside you are looking to see if the keepers are sunken into the retainers a bit more than normal. You can't see them in the pictures you posted because the rocker is obscuring the view. If they are sunken in, that is a sign of cracks that will be apparent on the underside of the retainer if you remove the retainer. If not sunken, then you are ok.

Do you have any reason to believe the engine was mechanically over revd?

RolanTHUNDER

Could a vacuum leak or dirty fuel filter cause his misfire?

To the OP have you ever run good quality injector/fuel system cleaner? Try that if you haven't already.

Smirk192

Smirk192

s2000Junky

No not likely, since he is only getting a misfire on one cylinder. A dirty fuel filter sock would cause fuel starvation to all cylinders, and it would have to be pretty clogged, not likely in my experience with this car to ever have that issue anyway, and a vac leak would also not be isolated to one cylinder.

The components that are isolated to one cylinder starting from the top down are/

ECU
engine harness
coil pack
spark plug
fuel injector
valves
cylinder

Car Analogy

If injectors are really dirty, even sending them out for ultrasonic cleaning often only helps temporarily. It seems there is a point of no return. So its interesting that Techron treatment seemed to help, but only temporarily.

Perhaps its a sign of a too far gone injector.

RolanTHUNDER

I know what you mean.

RolanTHUNDER

Perhaps it is his fuel filter sock then. I've heard of the same issue being exhibited as a symptom of that and it going away once the sock had been replaced with a new one. Makes sense since that sock is not everlasting and over 100 000 plus miles even injector cleaner ain't gonna make it as good as new. At idle the fuel pressure is typically quite low so that's when dirt in the filter would inhibit flow the most. Once revving up pressure will increase helping fuel flow easier. Correct me if I'm wrong...
As for the coil packs, typically on our cars cylinder 3's coil pack gets drenched in oil due to the spark plug seals not stopping oil from getting in. they get hard and brittle over the years. Replacing them solves the issue preventing misfires caused by that but if the pack is too far gone as a result of oil soak then it has to be replaced in addition to the seals in the valve cover being replaced.

Chuck S

Too tight in my opinion, they should be at max clearance since they tighten in use, especially the exhaust. I believe the current "Billman spec" is 0.012" (twelve) for the exhaust.






-- Chuck

rpg51

I think OPs car is an 02 (ap1). My memory is that the OPs setting is the tight side of OEM spec and that Billman uses that in his own ap1, and recommends it generally for ap1s, unlike DBW ap2 cars. Could be wrong, but I think he has said that the ap1 gaps do not tighten the way the DBW ap2 gaps tighten up before the adjustment interval is reached.

I hope I understood that correctly, because that is how I have my ap1 set. Also, OPs setting is within OEM spec, and so it does not explain his symptoms.