Not sure what's going on, but I've been trying to tune a buddies 93Z and we've come across a problem. Joe Georger was kind enough to get a version of VEMaster done for me to tune VE tables on a 93, and it wouldn't work.
Well, I realized why really quick. The car in question is only operating in cells 16, 17, and 18. Why?
16 at idle, 18 at part and wide-open throttle, and 17 on decel I think.
Anybody have any idea what's going on here?
The car has a slight exhaust leak right before the left O2...is that making it go into some limp-home mode or something?
I do have the log I can send someone if they can check it out for...but it is a 93 and a different version of datamaster.

 

If it's not going into closed loop, it will stay in cell 18 during regular driving. Except, as you've already identified, 16 = idle, 17 = decel.

 

Yeah...I thought of that last night after posting. So I went back and looked at the file again.
When you first start the car, datamaster says it goes straight to closed loop. No open loop. Then it stays in closed loop all the time. Even at WOT...closed loop. Shouldn't it go to open loop?
I also went back and looked at the coolant temp that triggers the car into closed loop, and it's 32.75 Celsius. Same as stock.
Do you think that this thing is just stuck in open loop somehow?

To you guys using datamaster on a 93, does it ever show that your computer is going into open loop?

We have another computer that I think we can try. Just have to get it and try it.

 

Dan,

Just looked at the log you sent me and it looks like your ECM is not registering the SPEED. Unless you sent me a log where you were reving the motor in park/neutral. If thats the case you need to get me a real log (part-throttle driving & WOT)


Also, what mod's do you have on the 93 Camaro and is it a M6 or A4. The more detail you can give me the better off I can help. Also, is this car running of the stock ECM or a custom tune?



Wilson

 

Well, the car has an 11.8:1 396, ported LT4 heads and intake, custom cam (236/242, 114 lsa), hooker longtubes, mufflex y-pipe and 4" catback, turbo 400, 9" rearend, dual stage NX kit, and all the other little goodies. 42.5lb injectors too.
That log I sent you is all part throttle. Really no WOT. Not worried about that right now. I've got the wot timing figured out, and we need to get it on a dyno for the fuel.
The log doesn't show speed because of the turbo 400 and the fact that we haven't hooked up the speedo yet. Don't even know what we need. Weren't really worried about it, unless we need it for something?
The chip is half Ed Wright, half mine. Well, mostly mine now. I can send you the bin if it will help too.

Anything else you need, let me know. I'm pretty stumped here.

 

Dan,

Send me the bin and I'll take a look at it. Did Ed program for the 396? Also, it looks like the IAC counts are kind of off. From your log you sent me the IAC counts are sometimes in the range of 0 & 160Max Open. Something is wrong. I'll take another look at the log file tonite and i'll let you know.

 

The program Ed did was for 30# injectors. When I bought TunerCat I started doing his WOT timing stuff, and left the rest the way Ed had it. Now that we've added 42.5# injectors and noticed that the car was really fat around town, I want to do the part throttle stuff and see what happens.
I have taken percentages out of certain areas of the VE tables, but gave up doing it since Joe was working on VE master for these computers.
We have not been able to get the IAC counts in check at all. Tried drilling out the IAC passage like everyone suggests, tried messing with idle timing, fueling, and adjusting the throttle stop screw.
I think that exhaust leak has something to do with all of this. Hopefully the guy with the car will fix that leak so we can go from there (YOU LISTENING BRANDON!!!).
I'll send you the original Ed bin and what I have now.
See if anything stands out.

Do you think the speedo not being hooked up has anything to do with the car not using the other fuel trim cells?

 

Did Ed tune for the 396 engine? BTW- Before you do any WOT tuning you should ALWAYS tune your part-throttle first. It makes no sense to tune WOT if you cant get the car running right

 

OK, the chip from Ed was setup for the 396 and 30# injectors.
The car ran pretty good...went 121mph all motor w/ a 6 speed last year.
Then over the winter, the owner put the turbo 400, 9 inch, and bottle in it.
Then we decided to go with some bigger injectors. So I bought TunerCat and the stuff to burn chips. I changed the injector constant to 42.5 to coincide with the new injectors.
Then we decided we were going to just tweak the high map timing. Now I figured I'd do the VE tables to help with the part throttle stuff, then later we'd put it on the dyno and do the PE stuff.
I have a pretty good idea how to tune this car, that's not the problem.
However, I don't know why it is only using fuel trim cells 16, 17, and 18. And I don't know where to start.
We are going to fix the minor exhaust leak, try a different computer from a friend, and get the speedo hooked up.

Do you have any idea why it's only using cells 16, 17, and 18?

 

The best thing to do now is to fix the problems that you know about. That means to get the darn exhaust leak fixed right away. Once you get that problem solved try logging some new data. Also, double check to see if you have any vacuum leaks (intake manifold, TB, etc). This could be one reason why your IAC is pegging 0.

 

Dan,

The computer will never go to the other fuel trim cells unless the car is moving. So if your speedo is unhooked that is the problem. I have heard of at least one guy, on the lt1-edit list, who had done a similar conversion and used the abs sensor to feed the VSS signal.

What kind of injectors are they? Just curious if you took ford's different rating psi into account.....

Joe

 

I think your right. The computer probably doesnt know what speed is without something telling it. This is probably the main cause of the problem. Try relogging some data after you get the speedo hooked up.

 

OK, exhaust leak will get fixed. And we will get the parts to hook the speedo up and then see what happens.
The injectors are Lucas and they were bought from PT&E. I assumed that they were rated at 43.5psi...I thought I read that somewhere. Might have been on the Buick board though, they use those injectors more than LT1 guys.

Thanks Joe!