Got whats in the sig, and got a tune from Madz, even had him adjust it alittle after a few datalogs.

Car idles fine when u first start it in closed loop. O2s read about 940mv ..

then as soon as it goes to open loop when its warmed up, you can hear it start having issues with idleing.. but it keeps running. And the O2s start reading 200mv then jump to 1200mv and back to 600mv.. and just all over the place non-stop

It even jumps into closed-loop mode from time to time when its warm for a few seconds, and it runs 940mv for that time.. tried messing with a few things and i give up after 8 hours Saturday!

Nothing is wrong with Madz's tune.. and he's been really trying to help me, but i don't wanna keep bothing him like this.. so if anyone else can help me with this!

Thanks!

 

If you have Datamaster it would help to post a log to let others see what's going on. I think you have it backwards though, the car should start out in open loop and then go into closed loop when it warms up.

 

I was thinging that right after i posted it. I think your right.. but either way you know what i mean.

I'm actually at work right now, so when i get home i'll have to do that. I'll post an idle datalog and a WOT one.

 

Thats normal under cold startup.


This is also normal for the o2's to start cycling like that. Like the above stated it would help to hava data log of what she's doing. Does the idle go up and down or does it just have trouble staying running?.

 

she stumbles alittle then revs up... over and over... but only when its warm with either open loop or closed, whichever it is when car is warm.

Car runs great when its cold.. but once it warms up and is supposed to start watchin the O2s to do AFR.. it runs rough.. surges and doesn't have anywhere NEAR the power... ran a 13.6 the other night with a SLOW launch... but still only got a 104mph.. before cam i ran 13.98 @ 100mph.. i was little disappointed.. so i'm working on the tune

 

Thats actually not bad considering you have a untuned car with a cam. Thats almost what I ran with the same setup you have. Sounds like a tuning issue.

 

I know its a tuning issue.. i had it tuned 2 times by Madz and its still not right.. just was looking for some help before bugging him a 3rd time... not that i'm unhappy at all.

 

you have a pm

 

The problem is its not a tuning issue. Hotcam will run fine on a stock tune so you really need to look elsewhere. When you see the O2s jumping around, thats a good thing. They are doing what they were designed to do so dont be alarmed. Try to find somebody with Datamaster.. its the only way to really diagnose what the problem is without randomly replacing sensors and other things.

 

I'd have to agree. Having (street/dyno, etc) tuned so many hotcams (this is by far the most popular LT1 cam), it cannot be a tuning issue, especially since it runs fine in open loop.

 

A scan would be extremely helpful. It sounds like you have a sensor failing in my opinion but I would need to see the voltages to confirm that. I'll be amongst the other who check it out if you post the file later.

 

I'd love to post the datalogs.. but i'm having troubles getting a laptop... the one a normally borrow from a friend is down.. and no one else has one. I do have 2 full throttle and 1 part throttle blasts logged... but i don't think they are very helpfull.

I'll let ya know when i finally get a laptop to log the idle.