B20 has rough idle

[JDBenson]

Hey all. Got a B20 block/B16 head, S2 cams, high comp pistons running hondata. Cams at TDC. Had an issue yesterday where the car started a rough idle. The rpms still stay the same, you can feel a stutter in the engine as well a slight loss in power. Car is currently running a little lean as well as burning some oil. Checked the spark plugs and they seemed fine as well as the distributor cap. I let the car idle yesterday for a few seconds and it fixed itself. On my way home from work this evening I took a turn and the issue came right back up. I don't run the car hard and shift every 10mph. Any help would be appreciated. Thanks guys.

[green91]

There's way to many variables here to give u a good diagnosis. Was it tuned by a reputable tuner? How lean are we talking about? Do you have a wideband? What are your AFR?

If it's burning oil I'd start by doing a compression test. Its if you've got a ring/ringland issue its oil fouling a plug or something.

[D3UC3S]

You have 12 gears????

Sounds like something electrical if it does it intermittedly

[JDBenson]

Jim at motorvation tuned the vehicle. Aft is probably between 10-11:1. No wideband. Plugs seemed fine no oil on them. Don't have the equipment for a compression test right now. Does the info I gave you help at all? I appreciate your quick response. I wasn't expecting that. Lol

[green91]

Uhm thats very RICH, and its certainly rich enough to cause a misfire.

[JDBenson]

14 actually... lol. And i'm pretty sure the problem started when I added flames and a skull on my hood... you know, for the extra "HP"...

[JDBenson]

OK I might be wrong. I thought stoic was something like 14:1 so I'm probably giving you bad info on the afr... I know its not high since I lost a decent amount of power when my friend who is a mechanic lowered it for me. I was thinking of the numbers from the dyno sheet so I'm probably talking about something else entirely...

[green91]

If you hold it at a constant RPM (say 2000rpm) does it seem pretty smooth or is it rough at that speed too? How did your mechanic "lower it" ? and what exactly did he lower.

[JDBenson]

Its not as bad when its moving but it definitely seems like its misfiring or not firing one cylinder. He lowered the fuel ratio with the fuel pressure regulator. He's also fully certified by the ase and has passed all their exams.

[green91]

Yeah but the problem if the car was tuned at a certain fuel pressure and then he changed the FP, it changes the ENTIRE tune! Not just idle. ASE doesn't mean he knows shit about tuning a car. Anyone that will touch a AFPR without a wideband and a dyno isn't doing you any favor.

[1civic]

Sounds like a joke to me.. HA-HA!!

[JDMJ]

Jim at motorvation tuned the vehicle.

This is why. Go somewhere else.