WB says lean idle. ECMlink says 11.4 @idle. Timing sounds off, just started the other day. Any help

[smbgsx]

my 2g dsm isn't running right. My wideband shows around 16:1 at idle and ecmlink is reporting between 11.4 to 12 afrs at idle. Stft are 12-16 percent positive. At cruise I'm lean on the wideband as well. the car sounds like the timing is off at cruise and idle too. kinda the Subaru burble. if I stab the throttle or go WOT it seems to go away and AFRs are what they have always been and it still pulls hard. Its never had any running issues until the other day. it has link V3, lots of mods, a 6-bolt swap/1G CAS and I have some logs. Any help would be appreciated. I'm going to do a boost leak test and check compression this week. I also may pull the wrap off my cast-iron header to look for cracks. The only changes I've made recently are new front wheel bearings and
Brakes. Thanks for your time

 

[doubleclutch]

For ECMlink advice, please fill this out:

http://www.dsmtuners.com/threads/suggested-prerequisites-for-ecmlink-log-advice.511062/

A log would also help.

A few questions:
- was it running well and then stopped running right?
- is your wideband calibrated correctly (recently)?
- Does your narrowband (if you have one) agree with the wideband?
- Did you change anything before it stopped running well? Hit anything in the road etc?

Stabbing the throttle or going WOT puts it into open loop mode and switches the way it manages fuel. Probably why it seems fine. Sounds like you have a closed loop issue.

Maybe try locking it into open loop at idle and see if it corrects itself. If the problem goes away it has something to do with how your closed loop tune.

 

[smbgsx]

thanks for the reply. Yes it was running good before. It was tuned on a mustang dyno at RS motors in MN. I tried forcing open loop on ecmlink the first day it happened and their seemed to be little change. When I did lock open loop I think the afr on ecmlink moved closer to 13.3 at idle and fuel trims dropped to +5% instead of 12-15%. my wideband stayed lean I believe, and idle quality/misfire sound didn't improve. I don't know how to calibrate my WBO2 sensor. I tried finding instructions online but couldn't find any for my specific dynojet model.
My narrow and wide band agree with eachother. the narrow band jumps sharply at idle like maybe a misfire is happening (lean-rich-lean-rich-lean-rich.) almost in time with the idle. where as before is would move, but much more smoothly as if were cycling right around stoich like it should.
I will post a log of me forcing open loop, a log of me driving around with the current problem happening, and a log from a while ago when the car was running well. As far as hitting anything or bottoming out I cannot think of anything. the only changes I've made recently are wheel bearings and brake pads. it literally happened right after that, but I cant see how they would be related.

joyride is the log when the car was running well. mildmiss is me driving with the current problem happening.
thanks for your help.

 

[smbgsx]

So I ran the engine earlier today and shut down injectors one at a time. I noticed that there was no change in engine idle when I shut down cylinder #3. I did a compression test, about 20 mins ago and cylinder #3 shows virtually no compression. cylinders 1,2, and 4 show 165-170 psi. I didn't warm up the engine for the test because I figured I am just looking for a variance which I obviously found. I added some oil to the cylinder and there was maybe a 10 psi rise in cylinder 3. what should I do next? I have noticed my valvetrain has been noisier than usual around cylinder 3. could I have a valve that is stuck open? the spark plugs all look good, except cylinder 3's looks fouled.
Any help will be appreciated.

 

[doubleclutch]

Looks like you found your problem. You could pull the valvecover and see if you can see anything there. Did you jump timing? Probably should check that. You could have skipped and bent Cyl3 valves

 

[AdR]

^^^This...

Unless your build is new where you could have stuck rings but that's unlikely.

 

[smbgsx]

my engine is magnus stage 3, its older but only has 5k miles on it. I did have a shop take the cylinder head off last year and mill it down to correct some warp, I have maybe 400 miles on it since then. They're not a very good shop in general. but the individual who took my head off seemed pretty knowledgeable for the most part and a different shop did the machine work.
I took my valve cover off last night but didn't see anything obviously wrong. I was looking for a lifter that looked noticeably different from the others but didn't really see anything of note. Is there anything else in particular I should look for under there?
I was thinking maybe I should bleed the lifters? Do you have a good link for checking if my timing belt skipped a tooth? I don't have a upper timing cover so maybe a rock or something got in there.
I am really grateful for all the feedback, thanks.

 

[smbgsx]

I take back what I said about the individual who installed my head. I did say "seemed" though, ha. Half of my cam cap fasteners are NOT even finger tight and the exhaust cap for cylinder 3 can be pulled a half inch off its seat and one of its bolts is broken off in the head. FML!! what kind of other damage can this cause? I'm assuming a bent cam, but what about the valve timing? if the cam could lift up shouldn't the exhaust valve been opening later and closing sooner? do you think my bottom end is ok? If the cylinder was not able to breathe like it should and ran heavily rich, do you think my cylinder walls would have been washed down with gas and wrecked my rings?

 

[Vegas Smith]

Damn, how the hell did that happen? They did the entire install for you?

 

[doubleclutch]

That sucks dude.

All you can do is take you time to fix it and see what shakes out after.

 

[Dsmkauai]

You need to pull the head and inspect the damage. Only way to know for sure what damage is done.

 

[Jack be nimble]

Get a leak down tester and see where the air is leaking. But it looks like the head needs to come off regardless.
When the head is off put some kerosene in the ports to check valve sealing. Flip head over to do the other side. But with a 20psi result the problem will be fairly obvious.

 

[smbgsx]

They did do the entire install, im assuming someone got sidetracked during the torque procedure for the caps. I did speak with the shop owner and he said he will "make it right and not run from it". which is good, he seems like a pretty decent guy. But we'll see what happens. I don't have a leakdown tester. I am going to have the shop owner come to my house and look at the car and try to figure out what he's willing to do and what "make it right" means as far as money goes. Budget is kind of tight for me right now because I have an AMB aero widebody nearing completion and I have a lot tied up in that at the moment. I want to pull the head myself but I feel like I wont get any help from the shop if I do. If they're not going to pay for any parts that have been damaged then I will do it myself.

with a 20psi result the problem will be fairly obvious.

what specifically are you hinting towards with this? piston/ring damage or valve?

 

[Jack be nimble]

I dont know if its piston, ring, or valve. But it will be obvious, there will be a bloody big gap somewhere
I didn't have a leak down tester either. So I made one...but they are cheap on eBay, or the mechanic may have one.

 

[1990TSIAWDTALON]

Put a bore scope down cylinder 3 sparkplug hole and see what you can see.

 

[smbgsx]

this thread is long dead, but I hate when there is no resolution. so the broken bolt came out by hand and I installed ARP cam cap/tower bolts. compression was 170 across the board after that. I then installed a whole new fuel system and sd kit. retuned on e85 and am making 432whp at 23psi on a mustang dyno here in MN that I'm told is pretty conservative. the owner has ran 10.7's in his evo making 380 on that same dyno.
I am having a miss at 6500 rpm @ wot though. that recently developed after several tanks of gas. I started a new thread on that topic