will69camaro

iTrader: (19)

What do I need to look for? I just finished heads/cam/intake/etc swap. Everything runs fine, and it has a tune one it, AFR is good at idle and all the way to redline (6800rpm). However, when I sit and let it idle for a while (around 900-950rpm) I eventually get an SES light. Not sure what to look for or where to go next. Anyone have any ideas?

Thanks, let me know if more info is needed i post it.

William

98Camarod

iTrader: (43)

If a misfire is detected it should tell you what cylinder its coming from, unless of course its random. A blinking ses light is random misfire

Chris81

iTrader: (1)

Will, can you feel the misfire.. or is it just throwing the code?

The larger camshafts have a problem throwing misfire codes at idle, although its really not misfiring. The idle misfire tables can be desensitized so it won't throw the code.

transam45

iTrader: (2)

it most likely from your cam that is seting of that code

will69camaro

iTrader: (19)

Yea I cant feel it, it always throws it at idle (well the two times it's done it). I'll have Joe look at it some more and yourself Chris to see if we can get it worked out. I dont like seeing that SES.

Thanks for the help guys

William

hourang

iTrader: (6)

whats the code?

Chris81

iTrader: (1)

I've seen o2 sensors do it as well, mine got wet and did it in the rain last night actually..

The o2's could have been hurt from all the untuned driving.. i've seen that one too.. lol

will69camaro

iTrader: (19)

Damn I knew I should have waited to do O2s, but I had one go out so i just replaced both of them recently. Hope I didn't ruin them already. Not sure on the code number off hand but it's "multiple misfires detected."

We'll see what it takes

William

p.s. Thanks again for all the help so far keep tossing out suggestions if you got them

Chris81

iTrader: (1)

If its throwing multiple misfires (PO300), i'd be willing to bet on the o2's..

Its happened to numerous cars i've tuned.

Does it run WOT fine?

will69camaro

iTrader: (19)

Yep WOT is perfect. Car keeps pulling no prob all the way to 6800.

It's just at idle it sets it, and sometimes it seems to lug a little at light throttle.

I'll change O2's and see.

William

MLavigne Z/28

I had a similar problem with the idle. Mine would also miss badly around 2000 rpm. Seemed to run good above that. Pulled the driver side coilpack and found #7 had an oily substance inside the wire harness connector. I replaced the coil pack with an extra that I had and no more missing. Just can't figure out how that stuff got in the connector. Anyway, you might want to check those connectors out also.

will69camaro

iTrader: (19)

Will do, i've got stock coil packs with 100k on them about and they've been off a few tires recently. I did a visual inspection on them before reinstalling them after the heads/cam swap.

Thanks for more info,
William

vidal77boxing

iTrader: (15)

Throwing multiple misfires (PO300) is common after a cam swap. Your tuner will fix it.

will69camaro

iTrader: (19)

Thanks for the help, on a different note i just dyno'd the car...

I was hoping for higher but it's pretty good i guess.

410/385 That's about 90hp/50ftlbs more than i did before the swap. It will get better as i complete the freemods and bolt ons.

William

Chris81

iTrader: (1)

Will, 90 hp is a very nice gain.

Do you know the timing/AFR at peak torque/hp?

will69camaro

iTrader: (19)

I'll have to check to be sure, he's sending me the datalog from the dyno (HP tuner). AFR wasn't working through the HP tuner so it was on a standalone gauge. Got a little rich on the big end and he said timing was slightly conservative but not bad. Still work to be done yet

William

hourang

iTrader: (6)

try the vette rear o2 sensors, they have a better heater in them and they are plenty long enough for long tubes. ive seen that code thrown with stock o2s.

MLavigne Z/28

What Heads and Cam package did you go with? I just did a Torquer V.2 and 5.3 head combo and also got 410 rwhp and 365 tq. Seemed low to me but then again my car has 160,000 miles on it. I also just changed my stock maf to the Pace Maf. Runs much better now.