Hey guys I just got my 383 finished last week. The car flat out screams, it'll get sideways at 65mph in 2nd. Anyway I hooked up my auto X-ray to get some readings at idle. I'm a newbie to scan tools and tuning so could you guys tell me what some of this stuff means and if it's good or bad?

Throttle sensor: .66 volts
Oxygen Sensor: 580 volts
02 cross counts: 41
Block Learn: 128
BLK LRN Cell: 4
Integrator: 128
Idle Air Mtr Pos: 160 steps
Learned Idle Pos: 40 Steps
Spark Advance: 21.7 degs
Knock Sensor: 62
Knock Retard: 8 degs
Inj Pulse: 2.9 mS
Rich/Lean Flag: Lean

I didn't get a manual with the x-ray, it came with the car, so I don't know what most of this stuff means, although I have an idea. My main concerns are the spark advance and knock retard, I want to know if this is right or too much for idle. My idle was 768rpm and it said my desired idle is 1025, should I up it? Thanks.

 

read traxion's tuning articles above your post. much info in there.
to respond to all that would require a long essay on tuning terms.

 

I've read the tuning articles before, and the chip has already been burned and optimized for this setup. I just want a yes/no answer to some of these readings, I'm not expecting anyone to write me a book by any means. I'm looking for some quick answers as I don't have a lot of time right now to be reading pages and pages of articles.

 

Looks like you have some problems, first off you shouldn't have any knock retard at idle. Your getting knock counts from somewhere. Since it is at idle it probably means your getting false knock from something. Second thing is your throttle position senosor is too high. It should be around .44 volts. You need to adjust it. With it that high your ecm doesn't think your throttle is all the way closed. Also your blm and INT numbers are locked at 128, that means your in closed loop, was the car warmed up when you did this log? If so your not getting open loop. You might want to post the rest of your combo, mostly what ecm are you running, what chip (hypercrap,mail order,done by buddy,DIY,ect.), cam, comprssion and stuff like that.

If your getting all that retard all the time your loosing a ton of power. I'm ASSuming you didn't burn your own chip. If you had one burned over the phone you still have alot of tuning left to do. It's pretty close to imposible to get the tune right in one try. It IS impossible to do it without ever data logging the car.

 

Monte : please explain the rich/lean flag showing LEAN. my set up last spring threw a check engine code. i looked at it and the code was LEAN. in goes 90 lb injectors. problem gone. does the data log replace the check engine light function or can they work simulaneously? does lean flag mean SUPER LEAN or just a little lean? MOnte: EXPALIN YOUR COMMENT BLM AND int AT 128 MEANS IN CLOSED LOOP? if in closed loop would not the blm be corrected over time by INT and be varying? is this a snapshot of one cell only? no RPM listed? i may have my speed density 7747 tunercat mentality getting me confused.

 

The chip was tuned several times by the dude who owned the car before me. The guy had talked to traxion about chips before, so he knew what he was doing with the chip. The car turned 12 flat at 118 with drag radials, so it was pretty much on. The only thing changed in the setup is that the engine is now 12:1 comp. instead of 11.2:1. This may have been the reason for the knock, as I may have dilluted my 98 oct. gas when I put 93 in it. The car ran well with 94 when it was about 30 degs out, with no audible knock. But I guess 8 degs spark knock is a lot at idle right?

Right now I have the scan tool and a pocket programmer, I'll get the rest of the stuff to burn chips in a few weeks.

The car runs great, but it does hiccup down low around 1800rpms every once in a while, which a lot of miniram owners describe. When I did the x-ray it said I was in open loop, oh yeah, the thermostat is stuck open so the car had been driven, but it wan't warmed up, it was around 163deg F. I'm changing stats tomorrow, do you think the stat is why Integ. 3's are locked at 128?

The setup is: 383, Eagle ESP 4340 crank, Eagle 4340 H-beams, Wiseco 12 to 1 pistons, AFR 210 ported heads, ZZ-X cam 240/240 598/598 lift, Minram, rev kit, Super comp Hookers, true duals, 3200 Vig, Pro built trans, and 3:73 gears. Also 58mm TB etc, no stone has been left unturned except a 12-bolt and some misc. susp pieces.

The car screams even more than when I bought it, since the bottom end was coming apart and the wrong valve springs were on it. Right now the engine has about 150 miles on it.

 

Ronny: You got me ronny, closed loop means the ecm is looking at the O2 and is correcting it. Open loop means it is just running off of what is in the VE table. The rich lean flag is just a signal to let the ecm know what side of the14.7 the O2 is since it is continuosly switching back and forth. Now getting a lean error code is another problem all together. That basically means that the ecm has "run out of room" to adjust itself out any further. You 90 pph injecotrs threw it the other way. If you didn't do any chip tuning when you swaped the injectors I'm very surprised it didn't flood the engine with fuel.

Joe: It concerns me that your still in open loop at 163 deg. You should be in closed loop. If your O2 isn't up to temp then it won't go into closed loop either. That can be caused by either a crappy O2 that won't warm up, or an O2 that is too far down stream. If the chip is tuned correctly then the open loop thing could be causeing some problems. Also the extra compression has skewed your whole tune. I would be very afraid to run that much compression on a street motor. I would be very afraid to run the timing curves that were set up for a 11.2 to 1 motor. When your that high in the CR range things get funky. You really have to be on top of your tune. That cam is also extremely large too. Come to think of it the guy that tuned it might be running it open loop all the time. Some guys do that with large cams.

Basically there are too many variables to identify your problem with that small data log. You need to really start watching it and learning more about chip burning and tuning. I would give traxion a yell if the guy that tuned it talked to him about that car. Better yet track him down and find out whats goin on.

 

that make more sense. when the 90lbs went it the handwriting was on the wall as the "tuning fun begins". with that injector swap in goes the 7747 and puter lays on the floor since. BUT just the add on of the 90 lbs and the 7747 made the car run better day one b4 tuning . idle quallity was so much better. it was like i had a car again and that lingering fear of did i screw up this car was gone. only issue was the "stumble" and that was fixed with mucho AE. b4 the 90 lbs i tried the vafpr and that was OK on WOT but too lean on daily driving.

 

You would be surprised how well a car will run when it's drowning in fuel. I just tuned a 305 in a s-10 that was still running the 4.3 ecm and chip. It ran surpisingly smooth and never hickuped. When I started it would spin for about 20 feet. When I got done it would spin the tires clear through first and half way through second gear. This was just a quicky tune job that was no where near optimized. The tune almost doubled his fuel milage as well. But the truck ran fine before, no problems so to speak. If it had been lean the 4.3 would have been put back in the truck. When a motor runs lean it is very obvious. Whe I first started tuning my monte I had a new combo with 75 pph injectors and a cam that was't "computer friendly". It took me 2 days to even get it to idle without puddling fuel on top of the throttle plates. Now the car runs as strong if not stronger than it did with the carb, and I have added 4 mpg. I'm not even envoking high way mode yet. Chip tuning is the ultimate modification you can make to your car.

 

If you are running a cam with big overlap, it's going to make it seem like you are running lean though you aren't. You end up running rich. The unburnt o2 in the overlap gets to the sensor to make it think you are lean. Then the ECM adds more fuel. Move the O2 swing values down to .4 or even .3 and see if that helps. Does the exhaust smell like fuel?


Also you should open your throttle blades more via the screw, and reset the TPS To .54 Mv. 44 is too low. Your IAC values are maxed 160 is too high, they should be more like 30-40 even 50. Which means the IAC is open so far to get the more demanded air through.

Why is your desired idle above 1000? Were you testing things in open loop and cold? Try it in closed loop at normal operating temperature.

Also, figure out why you have knock. Knock is bad. I run 28deg timing at idle.


You aren't really running 12:1 on a street car are you? What octane fuel do you have in there? Hope that cam has alot of overlap.

 

Guys my scans were done when the car was cold basically, because the stat is stuck open so even if the car had been warmed up it wasn't "really" warming up in temp. I think that the gas in the car is to low of an octane #, that's why I'm getting knock. This car is mainly for race, but it will be driven on the street a few days a week. I did have a 12 to 3 ratio of pump gas/toluene mix, which made the octane 97.8. Right now my amount of toluene only brings my octane to around 94.5 I'll add a couple gallons of the 117 to see if that helps the knock. Oh yeah here's what's going on when the cars under load according to the x-ray.

1600 rpm 33.6 adv. 8 deg knock
2244 35.7 10 deg
2435 39.5 10 deg
2800 38.5 9 deg
3024 36.0 11 deg
3681 34.6 11 deg

This has got to be from my race mix getting dilluted from adding 94 oct. from Sunoco. Oh well, at least I know what I can't run.

 

Your problem is timing. Re-check your initial timing. You will have to reduce your timing via the main spark advance table per rpm, or just turn down the inital about 10 degrees as a quick fix.

You could have chip with lower timing for pump gas for the street, then a chip with more timing for higher octane gas, but it wouldn't pull as hard with the pump gas.

 

Still looks like you have way too much timing. As said before, check the initial and set it to 6deg BTDC and tune in the chip!

 

Thanks 89gta, I'm actually getting ready to go out and change the stat, I've just been lazy. I have to go buy another timing light as well, cause mine was never returned to me. Anyway this car runs wayy stronger than when I bought it. And this is with this spark knock going on. One more thing I wanted to ask is 10 degs knock retard throughout the rpm band hurting my engine really bad? It's only had this gas for about 30 miles. I mean is this much knock hurting my power currently, I'm just curious?

 

Thanks, I'll be doing this right after I change the thermostat and buy a timing light. Oh yeah, I gotta get some chips to burn with and the prom eraser.

 

Just use the EEproms and don't worry about the eraser.


Oh and the knock retard isn't hurting anything but performance. If you can't hear the ping/knock (audible knock) then it wont hurt anything. That's why we have the sensor, so we don't hurt anything.


It's possible you have your knock sensor in too far/too tight which makes it more sensative.

 

Where can you get the eeproms at and how much are they? Thanks.

 

Go read traxions Programming Proms 101 tech article. Tells you where to get EEproms (I get mine from Craig Moates) aswell as how to program them and stack them.