Car is a 95 z28 auto with a 97 engine with hand ported heads and a small cam,longtubes,ORY,magnaflow catback,accel 26lb injectors and a racetronix 255lb fuel pump.

The guy i got the engine from said the cam was in the 215/220 range he also said the engine made 390rwhp through an m6....Guys i am stumped i know i need bigger injectors and a larger stall but can you look at this datamaster log and tell me if anything weird is going on?

The tune in the car now is from madz28 when all it had was shorty headers,accel 26lb injectors,intake and catback so i know the tune is way off.

http://www.mediafire.com/?8r38pl1ajkn99o5

Im using tunerpro v5,freescan,tunercats winflash and datamaster

my injector constant is set to 25.61

 

Quick scan over the data-

Seems screwed up. It's idling in Cell 8 (although it slips into Cell 5 at times), rather than Cell 16 - second time I've seen that recently. Decel in Cell 3, not Cell 17.

IAT is showing -40*F, but its not setting a code. That's in the last 1/3 of the log. In the first 2/3, IAT is jumping all over the place. Appears to have bad wiring.

Right bank LT is maxed out at 160 in Cell 8 near the end of the log and its adding a bit more fuel with the ST. Left side LT's appear to hover around 135. In Cell 11, the LT's are below 128, so when it enters PE mode, it locks the LT's in Cell 15 at 128. When it goes into PE mode with the 128 LT's, the right O2 indicates well over 1,000mV while the left side is not exactly low, varying mid to high 900's. In one case, it stays in Cell 11 in PE mode and locks the LT's at 128, with the same extremely rich indication on the right side.

MAP at idle is about 63kPA, which seems high for what you indicate is a small cam.

Knock retard all over the place.

Frequent data errors in the log.

 

Thanks for helping me out lately injuneer i really apreciate it! So i took the IAC off and tested it and its not registering anything the wire diode thing must be severed its not registering any olhms at all. I also have a strong suspection that the wire on my right o2 sensor is messed up. I had to change that knock sensor and the coolant that came from the block wet the splices the guy who put the motor in the car made. before i changed the knock sensor i was able to run freescan and my o2's were acting pretty normal and my st blm were in the high 120's. Also the right o2 seems to get pegged at 1.092v sometimes and it will stay there and then suddenly it will drop to like .100v and just stay there for a few minutes without fluctuating?

And your indicating that i might have a larger cam from my MAP reading 63kpa? Because honestly i have no idea but what he thought he could remember lol i know but its all i got to work with. I tried to bump up the closed tps spark advance from 20 to like 32 between 800-1200rpm and the car ran terrible.

 

replaced both o2 sensors and used my racetronix extenders instead of splicing and got a new iat sensor. Bumped the closed idle spark advance to 26ish and raised the idle slightly and here is my new log. Car runs much better but it still getting knock retard! Im thinking the injectors are just to small what do you think?

http://www.mediafire.com/?gu3cdzex6d10qqg

 

Why did you do anything at all to the IAC? It was working fine in the data log. Idle was holding programmed RPM, counts were OK, counts were increasing as speed/TPS went up? Or did you mean you checked the resistance of the IAT sensor, and got no readings? Its not a "diode", its a "thermistor" - a resistor who's resistance varies inversely to tmeperature.

The only time I see the right side O2 sensor hanging above 1,000mV is when it goes into PE mode. Watch the "flag" for "Pwr Enrich Enb". When it goes to "1" (as opposed to "0") its in power enrichment mode, the O2 sensor feedback is ignored, and the A/F ratio is significantly richened to produce power. But crude as they are, readings above 1,000mV on a narrow band sensor are generally a good indication that its running way too rich in PE mode. 1097 may be the upper limit of the binary field. You may be poouring in enough excess fuel to damage the engine.

When MAP is higher than it should be at idle, it may be a bigger cam than you think, or it may be a small cam with a so-so tune, or it may have misadjusted valves, burned valves, low compression, misfires, vacuum leaks, etc.

I suspect that the fact it is in the wrong cell at idle may be related to the Cell boundaries, and the MAP issue, but I'm not an LT1 PCM "tuner" - I ditched my stock PCM 11 years ago, and run an aftermarket system.

Why did you increase the closed throttle spark advance?

 

Do you have the EVAP system connected fully, and operating? Same with the EGR? Your knock retard often shows up when the PCM activates the EVAP purge, and/or EGR.

 

Here goes i havent touched the IAC valve im sorry i ment to say IAT sensor sorry for the confusion.And yes it gave out no readings so i replaced it and now it is reading like it should.

I raised the closed throttle spark advance because it i read on here it helps burn the fuel at idle caused by the scavaging effect of the larger CAM.

How do i get the car to use the CELL's correctly? it never goes into CELL 16 when at an idle. actually its not using any of the CELL's it should be lol.

And yes the EGR system is operating and fuctional. But the EVAP has been disconected but i can hook it back up and see what happens.

 

So ..DAMN.. who did you end up contacting to fix this? I have the same problem with my car not using the proper cells. So id like to have it fixed of course haha.

 

He answered in my thread on the Cell boundary issues:

https://www.camaroz28.com/forums/sho...50&postcount=8

 

Yeah I found someone to do this for me since I do not know how to do it...