Yep. My bad O2's were telling my Uprev tuned ECU bad info and the car would not run for poo. At about 2500 rpm car cut out like it was bouncing off a monster rev limiter. I could be totally wrong but I would check out the O2's and at least cross them off your list.. Again, just my .02

 

The stock ECU is not (should not be) controlling fueling so...

 

not that it's affecting this situation, but I'd knock the gap down to about .038 when you start boosting more. good luck with the solution.

ross

 

update: so of course, stock injectors, stock ECU no codes, no misfire.

The car runs really lean and breaks up some, but if I bumped my fuel pressure that would probably take care of that.

So it can be 2 things,
bad haltech, or the coil ground I moved to the battery fixed the problem.

so took 1.5 hrs to get everything swapped back to stock for a 5 min evaluation. Now Time to put everything back to the way it was and see what changes...

Honestly, no wonder why shops charge so much and have cars for soo long.

fingers crossed the ground location swap fixed it.

 

Before swapping out the injectors would it be wise to stick in the haltech again and use copy through on fuel and ignition. Not a definitive test but the car should sort of run the same as your oem setup as long as your dead times and other options are set appropriately.

ie: change one thing at a time to try and isolate the issue.

 

ahh duh! i couldnt get it to even start using the haltech. I tried that 1st becuase I had all my stuff soo cleanly up in the dash and didnt want to have to do that again.

Totally forgot about copy thru, although cranking values are prolly what is the starting problem

What values should I put in for the post start enrich, etc, as the thing wouldnt even catch when I turned the key?

No idea on dead times either, just used what was in the base map for the 350 that came with the Haltech software. Searched but no dice either.

but if I cannot come up with starting values, not much else I can do but swap back in the 1200s. I just dont have enough experience to know what are 'normal' ranges.

 

So for stock injectors, I would go back to the base map for a stock car. You have to reset the option to use high impedence circuit (easy to forget). Cranking fuel ms should be significantly higher than for the HKS 1000 cc values but hopefully the base map is good enough starting point to start the car and just keep tweaking up till it starts easily...

(I didn't know that the Haltech had copy through for fuel - never tried that)

 

ya I set all the easy stuff. The base map wouldnt start the car though. I'll try the copy thru and do it again today before I take the plenum off again.

 

Hey the Haltech does allow fuel copy through! Not that it's any use to me.

Maybe check with Hal or Sharif about cranking values and prime pulse values to get stock injectors to fire up?

 

The default Haltech 350z base map should start the car up with stock injectors, though you may need to play with the fuel pressure since I believe you're running a RFS. One thing to check is to make sure your coolant and air temp corrections are zeroed out in the cells that affect cold start, they could be throwing you way off if not yet calibrated.

 

thanks, i'll try it again today. I think not having copy thru is what killed it. fingers crossed it runs fine.

Then maybe I can move on to the next thing

 

A while ago I found values someone used for HKS 1000 cc inj on this site with the haltech.

At 12v - 1.400
At 14v - 1.100

I have no idea if these are correct as I only run PE510's. Hope it helps and don't forget to set the impedence (as RCDASH mentioned) and also the flow rate.

 

ya i tried to start it with teh copy thru and its just too lean to run properly. No miss in the short time I had it running, so im just going to swap back in my normal injectors and give it a whirl

 

You can just bump up the dead time to increase all cells at once by that amount (the dead time is just added to whatever the final IPW is).

 

i didnt get any misfire codes when it was running and with it setup the other way, i'd get a pending mis p0300 right away I think.

I might try increasing the dead time tomorrow before I pull off the plenum. It wants to idle at like 18+:1 so i'd need a pretty good increase I guess

 

well I swapped back in my bigger injectors and the Haltech and it misfires again.

So stock ECU, Stock injectors -> no misfire.
Haltech and aftermarket injectors misfire

So I am thinking I have a bad unit for 2 reasons

1) From day 1 it was grounding my aux output when the key is in the ACC position (which I posted about on 2-20-10 before I even started the car https://my350z.com/forum/8160365-post759.html) . I noticed that bc my meth pump would turn on when I would go to start the car and then shutoff when the key went to the 'ON' position. Hal suggested that I power my trigger relay with +12V source thats only on when the key is in the 'ON' position (ie fuel pumps). But that does not address the Haltech problem...

2) I swapped the car back to stock using the stock ecu and stock injectors and there is no misfire under no load. Swap back in Haltech and 1200cc injectors and misfires again. This is with 2 different set of injectors, normal no load AFR (13-15), no drop in fuel pressure, stable battery voltage, no vacuum leaks, and on 2 sets of spark plugs (brand new ones and seasoned ones from my Vortech motor)

It ran just fine with the stock parts so the sensors (cam/crank) are fine as well.


I bought it brand new from Forged, so hopefully we can get something worked out to figure this out

 

I've been reading your posts. I don't have the problem with misfiring, my problem is my Z locks up @ 4200 rpms. You can have her floored and you feel that the old Yugo has more power than ur Z. Soo I back off the gas for bout a second, than mash down on the gas. All of a sudden she kicks in.
Any thoughts?

 

str8dum1, for both those issues, I think it could be a harness miswire also... I wonder if you're car being an early 03 is any issue?

 

I guess you'd imagine it woulda been encountered by now if it was...
I wouldnt even want to try to trace wires on that harness though

Hopefully I can get ahold of Sharif tomorrow. I'm getting bored of pulling that plenum on and off. Thank god I have a Cossy, bc if I had to undo 2 sets of bolts each time, i think the car woulda been in the ditch by now...

 

I'm definitely not a master of electronics in cars but here's what happened to me and maybe you could check it on yours.

AFR dipping, generitc p0300 misfire code. It would do it on occassion and i couldn't reproduce it with one certain thing. It would happen under load and sometimes while just idling but mostly under load.

After going through everything for weeks i found a loose connection at the injector clip of #2 causing a bad connection. Competely random that i found it but that was the issue.

Maybe pull the plugs and check to see if one is whiter (not burning) and then check the injector harness for that cylinder.

There sounds like more going on with yours but sometimes it can't hurt to check simple things.