twcblackhand6970

The right side is the one that is acting up and that is the passenger side. I replaced the right sensor awhile back because the right sensor connection was burned. And the left side is the one that sounds like a diesel.

twcblackhand6970

I went to drive my girlfriend's focus today and was listening to her motor. I think the diesel noise I was explaining earlier sounds more like a DOHC motor like my girlfriend's car has. I'm worried about what could be causing this and if it's doing any damage.

dbrunner2

You mentioned that unplugging some injectors made more difference than others; which ones had the most effect? I'm wondering if maybe some gunk dislodged from somewhere in the fuel system and has messed up some injectors.

Also, does the diesel/DOHC-like sound change at all with the oscillation between BLM cells (what I was talking about in my last post, where the right side integrator drops very low and then resets when the BLM cell changes)?

Injuneer

He's not driving a Taurus. Its an LT1. Typical CTS voltage vs. temp in *C

2.20V = 44.0*c
2.49V = 55.3*C
2.75V = 65.0*C
3.00V = 68.0*C
3.25V = 84.5*C
3.51V = 94.3*C
3.63V = 98.8*C

If you check the frames in the 3190 range, his CTS is reading 3.51V and the data log is showing the coolant temp as 94.3*C. There is nothing wrong with his coolant temp sensor (CTS). The voltage and indicated temperatures change repeatedly over the course of the log, and correspond to the above table.

I've reviewed hundreds of LT1 data logs for people, and his CTS it NORMAL.

Injuneer

Some observations. At the end of the log where its idling, the IAC looks a shade low (12 counts) and the MAF looks a bit low (less than 6 gps). Possibly there is air entering the combustion process other than through the MAF and the IAC passage. Not a lot.... you are just a shade low on both of those readings. Spark advance looks high at ~35-deg at idle. I'm used to seeing values in the range of 18-22-deg.

Obviously a problem with the fuel on the right side, its pulling 12.5% out of the right side at idle (Left = driver's side = Bank 1 = cyls 1/3/5/7; Right = passenger side = Bank 2 = cyls 2/4/6/8).

My experience is that you don't learn much by sitting in the driveway and blipping the throttle. When you do that, you end up with data for Cells 18 and 17, and both those are calculated from the other cells. They don't mean much on a stand-alone basis.

For general guidelines on readings for a stock engine, look over my online LT1 scanner guide:

http://www.injuneer.com/ScanMast.htm

twcblackhand6970

So I'm halfway through your write up and have a question. Could my left bank being lean possibly really be a misfire making that DOHC engine noise, like a knocking?

twcblackhand6970

I just went outside to down the closed throttle spark advance to 16* and did a cold start data log.

Here's the new log link:
http://fb.esnips.com/doc/555519a7-df...39b41/testCold

Seems like the left is lean by a pretty big block learn of 141 and the right is rich with a block learn of 123. (If I remember correctly.) Since reading injuneer's write up I'm thinking maybe its a cylinder not firing making that noise instead of a solid combustion and making a false lean condition. What do you all think?

dbrunner2

High BLMs or integrators mean the mixture is being enriched, so you're half right; a cylinder failing to fire on the left bank will leave unreacted oxygen in the exhaust, which will be registered as a lean condition. However, since the computer is trying to compensate for this lean condition, it dumps more fuel in the left side, so it's actually running rich on the remaining cylinders.

In my experience, misfires don't (generally) make a knocking noise.

twcblackhand6970

Well that's ruled out.

twcblackhand6970

Took a video of the noise. Can't really hear it too much on this video, but you can hear it.

http://www.esnips.com/doc/53dba42c-e...ebdfe/P3090764

I tried adjusting the rockers with the engine running technique and the valvetrain sounded a lot quieter, but then I restarted it a couple hours later and it sounds louder than before so I'm going to redo the adjustments tomorrow.

twcblackhand6970

I will try to go data log with a drive around later today and post it here asap to get this blm split locked down.

twcblackhand6970

Took a quick drive around and here's the log.

http://fb.esnips.com/doc/cd810fc6-08...8ff7/testDRIVE

I already backed the timing where spark timing occurred. Hopefully this run will tell me if there's any problems with the o2's.

Injuneer

The link went to a "crush center"..... something about "one of your buddies likes you". Might want to check the link. I didn't want to risk waiting for the "picture" it was attempting to load.

twcblackhand6970

I recopied the link, it worked for me, but maybe it's because I have a membership.

Injuneer

Worked this time. But in 10 years of reveiwing data logs for people, that's the largest file I've ever seen.... more than 27,000 records and almost 30 minutes of driving. Gonna take a while to look this one over.