24x hell
As far as having to crank it after it is hot points to being to rich, dumping too much fuel at crank. The older ODB1 ecms have a crank fuel table that allow you to change how much fuel is being dumped at start up vs. coolant temp. Next time its hot and you have to crank the snot out of the car to start it, put the gas pedal to floor. This will put the PCM in clear flood mode and stop the injectors from firing. If it starts then you know it is dumping too much fuel.
EFI Connections website says they are doing inventory and site updates, Mike did input above though, so I did set the fuel as one value as he told me to. I guess I'll set it even lower though as 3.78 seems too high, even though that is what that spreadsheet I posted a link to above calculates it out to.
EFI Connections website says they are doing inventory and site updates, Mike did input above though, so I did set the fuel as one value as he told me to. I guess I'll set it even lower though as 3.78 seems too high, even though that is what that spreadsheet I posted a link to above calculates it out to.
Also what file did you start with? did you use a file from the eficonnection site that he shares?
I started with the file that comes loaded in a 411 PCM. Then I had mailed this file off to EFI Alchemy last November. I installed the 24x system, car barely ran but I limped it up to Jacksonville. Got it tuned, it ran OK, but was plauged with issues from the start, like we couldn't get the TPS to zero out. It ran like garbage when cold.
Then when I drove it PA this summer is when it started running like garbage all the time. Troubleshot it when I got back to FL, figured that some of the old injectors were leaky, as the car never missed a beat with three of them unplugged.
So now here we are, I have EFI Live sitting in front of me and capable of making changes, but what in the world do I change things to?
Anybody have the 24x, a cam close to the cc503, and can read their tune file? I'm curious what theirs looks like compared to mine.
Well if megaupload sucks please recommend somewhere else I can upload my logs to.
I'm not too prideful to admit to being wrong...so let's see this table, please.
Consider that GM has used the 12200411 "LS1" PCM for both Gen 1 SBC and Gen 3 LS engines. GM also used the E67 ECM for both Gen 1 SBC and Gen IV LS engines. In both cases, they swapped the firing order in the wire harness at the PCM/ECM and changed the injector to bank assignments in the calibration for closed loop fueling. If the firing order can be changed in the PCM/ECM calibration, why would GM not have done so?
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I just set that up with a SBC Firing Order..it's the Tune from my MCSS.
You dont have to mess with anything on the Coils or Injectors..that table right there you are telling the PCM what to fire and when to fire it. Simple as that.
Last edited by S10Wildside; Sep 16, 2011 at 12:36 PM.
The hard hot restarts look like what my car does if I don't wait for the fuel pump to prime (I have a bad check valve on my fuel pump). Whatever the actual cause, it is a lack of fuel getting in there, either from the mechanical system or the tune or even a bad sensor or connection. Go step by step and rule things out. Easiest thing would probably be adding some cranking fuel at hotter coolant temps and see what happens.
Oh yeah, as far as the injector flow rate and battery offset go, the flow rate MUST be a constant number with a vacuum referenced regulator or the car will be totally untuneable no matter what else you change. Finding the correct value would be nice but, in the absence of that, setting it to 1 across the board will at least make it possible to tune. Messing with this value at all will have a massive effect on the fuel side of the tune. The battery offset isn't as critical. You can leave it where it was as long as it is a reasonably shaped curve. You can fine tune it after you are done with all other fuel tuning by adding electrical loads with the engine idling and monitoring A:F changes. The table is there to keep the A:F constant no matter the voltage level. Of course, you have to do this in open loop also or you are just chasing the o2 sensors around.
Last edited by 05HD; Sep 16, 2011 at 01:45 PM. Reason: Added info










