RBob

iTrader: (1)

The high MAP malf is an issue. Once this is set the ECM goes into N-Alpha mode and creates a MAP value. This is done from the current TPS% & RPM, which on a modified engine isn't going to match reality.

Getting a MAP high malfunction on a modified engine is common. More so when starting to tune.

To correct the false MAP high malf need to set one value higher. Just checked the 7747mine.ecu and that parameter is not there.

It is location $539 in the BIN. The default is about 68 KPa. Need to increase it to (probably) around 76 Kpa. Use a hex editor and change that location to $BA, that is 79 KPa.

RBob.

Ronny

iTrader: (1)

Open loop jsut means you are running off the tables without correction from the NB02 sensor. When you run a larger cam often the NB02 often provides too much fuel. without the NB02 reporting the A/F is more stable. I run OL only at idle but did run OL all the time a couple years back but mileage sufferred as well as enviormentql air temps vary so much here in Wisconsin.

How does vehicle behave when in neutral? can you get BLMs to change in neutral when running various rpms? have you tried upping commanded idle RPM or consider commanding 750 but physically upping RPM with the throttle stop screw(i have 0 steps for IAC at idle so running off the throttle stop screw)?

A WB02 would answer a lot of questions.

Blazin4x4

Is the screw that opens the throttle blades the throttle stop screw? Because I've gone from almost closed to half way open to all the way open and there isn't much change... My iac counts in park or neutral are between 10-15... but I forgot to check where they are at during stalling when in drive. I tried raising the commanded or desired closed and open loop rpm but the symptoms didn't change.

I was reading one of the stickys in diy that said cam overlap can affect an N02 and a wideband to the point where it won't be accurate.... that is why I've held off on the WB. I think it would help though. How much, if at all would cam overlap affect a wb?

RROB: I'm idling at around 65 kpa in P, when in D (before it dies)it shoots up to 90 kpa... Is that because its going into N-alpha mode? Should I try a higher value then BA, i.e. 79? Also just curious I used a hex calculator and BA is 186 in decimal. Does that get converted again through hex to represent the value of 79 kpa?

9C was in location $539 before I changed it... is that correct?

Also I've been switching between 7747mine.ecu and bitchty.xdf to change things in the .bin that one alone can't do without hex editing. Is that okay or do I need to use just one .xdf and stick with it?

vernw

iTrader: (2)

That screw that opens the blades is supposed to be the way you adjust the min IAC settings. I'm not TBI expert, but if that was a TPI set up I'd say you either have a massive vac leak somewhere or your IAC isn't working....

JohnL

That's the base air adjustment screw. You won't see any rpm change until you run the IAC out of steps. Datalog and watch the IAC step counts as you adjust the screw.

This shouldn't be an issue with a cam with only 222° at 0.050". However, you have only 65kPa at idle which as Vern says sounds bad enough to be a vac leak. I recently tuned a car with 242° at idle and it had 65 kPa (after getting the spark right).

Watch it when it goes to 90kPa, and if the CEL switches on at that point, that's the problem. It sounds like you need more advance at idle (and probably off idle too). Check other posts and you'll see that Delco ranges are often 0-255 and that's why the hex conversion is 186 for 79kPa.

No problem switching .XDFs as long as they are both correct in the addresses they supply.

John

RBob

iTrader: (1)

To convert from the BIN decimal value to KPa:

KPa = N * 0.369 + 10.415

With N being the BIN value.

The $9C is about 68 KPa, so that is correct.


When the MAP shoots up to 90 KPa, is the engine RPM starting to fall off?

RBob.

Blazin4x4

Advance doesn't help neither does retarding it. As far as a vacuum leak I think it acts like it has one... surging and dieing under load... but those are also signs of a bad tune. I have sprayed wd all over the place when it's running and no change in rpm... I've even pulled my manifold and put new gaskets on the thing. No change.

Iac steps are 10-15 when it's in park... then they increase steadily as the rpms drop when in D until it dies. It went from 10 to 63 in five seconds.

What is CEL?

While I'm at it I got a Prom malf flag and an est (electronic spark timing) malf flag... Could these potentially be big problems?

vernw

iTrader: (2)

CEL = Check Engine Light

And FWIW, I don't think WD40 is a good vacuum leak detector. You need something like starting fluid, brake cleaner, etc - something extremely volatile (or water and look for it to bog down instead of speeding up).

And yeah, a MALF and EST flag are pretty serious. You probably need to resolve those before worrying about anything else.... at least IMO.

JohnL

Check Engine Light.

Is the Pope a Catholic?

John
----------
Not just IYO. If he has a PROM Malf, it's in limp mode and it doesn't matter what tune he has on the PROM. At least this is the case on the Delco ECMs I play with.

John

vernw

iTrader: (2)

I know, I was just trying to be nice....

Blazin4x4

What about est... how major is that? Or does that just mean it's advancing the timing?

vernw

iTrader: (2)

That probably means it is not advancing the timing per the timing tables in your prom....

Ronny

iTrader: (1)

if in limp mode that should show up in data log !! i believe it will show up as flag. this may be the answer! my car wont run in limp mode either(due to mods) !

Dominic Sorresso

My car will run, but I think its probably on 3 cylinders.

JohnL

If in limp mode with a PROM malf, you can't datalog.

And vernw is being nice again- the timing is locked!

John

Blazin4x4

Why would I be in limp home mode? It would only throw a prom malf flag right about when it dies... sounds like I may have found my culprit. What would cause limp home mode and how can I fix it?

Also why would the timing lock? Can you guys elaborate?

Rbob

I tried to change the value in hex but when I save the .bin then reopen it the value isn't what I saved it at... its 9c, what it was originally. What am I doing wrong?

RBob

iTrader: (1)

Once the change is made use the Hex Editor menu and select Action -> Commit Changes.

Then close the Hex Editor and use the TP menu to save the BIN.

RBob.

Blazin4x4

oh... thank you.

So what should I do about the prom malf?

Should I just swap out for an easier cam to tune?

JohnL

You're missing some important basics here.

You are not having tuning problems because of the mild cam you have. The PROM malf indicates that the ECM can't even read your tune (calibration). It is apparently in limp mode, and that's regardless of what cam you have in the engine. You cannot get anywhere until you get the bin you're editing burned onto the PROM you're inserting in the ECM.

Go back and read about how to burn the calibration onto the PROM. Then do a burn, and read the calibration back from the memcal and save it to disk. Then verify that the program you downloaded from the memcal is the program you intended to be there.

This is the frustrating part of learning to tune Delcos. There are some simple things you're doing wrong. Once you're over this part of the learning curve you're .

John

Blazin4x4

See now this is what burns me (pun intended). I'm using a pro version of the prominator... all I do is point and click and it will tell me if the upload was successful or if it wasn't. I've used the verify feature on the prominator program and everything checks out... so maybe the .bin isn't compatable? I have no clue here (as you can see). If the upload is succesfull why wouldn't it be able to read the prom?

I agree that I'm not over the learning curve yet but I think I'm getting closer and closer with every reply from you guys.


I apologize if I'm still missing something...

RBob

iTrader: (1)

Just look for the SES blink at key-on. If the SES blinks the ECM is running from the PROM(inator).

After a minimum of 10 seconds with the key-off, do a key-on, engine-off. The SES should come on briefly, blink off, then come on solid. If the blink off occurs your gold, turn the key and start 'er up.

RBob.

Blazin4x4

Ses? I'm sorry... not sure what that is. The light on the prominator swicth?


So if the ses test checks out but I'm still getting a prom malf I'm ok?

JohnL

https://www.thirdgen.org/forums/faq-...ht=ses+acronym

Ronny

iTrader: (1)

that test may not be specific to Prominator but i was told as you are that that is test to confirm the .bin successfully loaded. when i first used Prominator I had some concerns as well that I was successful on initial upload. unsuccessful caused a rapid blink if i recall. my car would not run on calpack so that too was a strong indicator of "chip failure".

ps. hide your women and children in S. WIsconsin the "vette" is out of barn and roaming streets. Hurley or Bust..Silver Street here we come!

Blazin4x4

Well I got no ses light at all. What does that mean?

I am getting data, not to mention the tune changes with the upload ( someone said you can't datalog in limp mode). So what should I do? I don't know where to start to figure out why it would be in limp home mode.

Also since i raised the point where the ecm goes into n-alpha mode I'm seeing 100 plus kpa with the same dieing problem.

Ronny

iTrader: (1)

As RBob said "After a minimum of 10 seconds with the key-off, do a key-on, engine-off. The SES should come on briefly, blink off, then come on solid. If the blink off occurs your gold, turn the key and start 'er up."

if you are seeing this you are runnin on the .bin you created.

No SES or CE at all you say? did you ever have one?

randy4762

Blazin4x4,
I have been following this thread all along hoping it will help me, and it has. I may be new at tuning gm ecm's , but I had a similar problem with raw fuel in the exhaust as you said earlier in this thread. Something made me watch the injector spray pattern and I noticed alot of fuel on the throttle plates. Alot as in almost puddles. I traced it down to a bad gasket where the injector pod bolts together. I tried to re-use it one to many times while dialing in the fuel pressure. Sometimes fuel injection makes you forget about the basics so, when I have a weird problem I establish all of the known basics first. My 88' Camaro seemed like it had a dead cylinder and all it turned out to be was a pinched fuel injector wire causing it to stay fully open and filling the crankcase with fuel. Also if you have that much raw fuel in the exhaust, find the source and then change your oil.That much fuel in the oil will cause tuning problems even after you find the original problem. It takes a good long highway trip to get oil hot enough to boil out all those short trip contaminents (fuel, moisture,etc)
Furthermore,
I peeked at your bin and in the 3d view in tunerpro I noticed a large jump in the main fuel table #1 800 rpm-80kpa site the value is 50. Did anyone else see that? That can't be too good either.
Don't take my advice the wrong way, I hope it helps. If I lived closer I stop over to give you a hand.
Regards, Randy

Blazin4x4

Um, I think I may have been too riled up and frustrated when I did the test. Now that I think back I have always seen the cel come on when the key is turned on... and it blinks off I think. I'll check again tonight.

Randy:

I wrestled with the holley for a while... it's spraying the way it should now but I have already put 200 bucks toward new injectors. Injectors were fine... They just weren't sitting in the pods the way they should have, then the nut that holds them in was loose causing raw fuel to pile into the manifold but it's good now. The ve table was an old one. Now I use the ve smooth tool and tune using percentages subtracted or added from the ve.

I beleive my rig has had 5 or 6 oil changes from all the fuel and I had a water leak. And the thing doesn't even have 20 miiles on it.

I appreciate the advice though it's good info but at this point in my battle I've been there and corrected it but I just don't knoow what to do about this wall I've hit.

So Is there anything else that would cause it to die consistently like that?

Also a prom error means it's "limping" correct? So why would it throw a prom error if its running off of the .bin?

Ronny

iTrader: (1)

my old ECU-7747 had a calpack(limp mode) for a V6. it would run car barely. It would die eventually i think. My new ECU 8746 I believe has no calpack so if the .bin does not "load" injs wont spray and car wont start. i think there were times when the CE was on and my malf codes showed a bad prom however. car ran poorly at idle and I think WB showed lean. I quicky realized in both instances the prom-.bin was bad.

Ronny

iTrader: (1)

If you can determine the engine is running on your bin and not limp mode is there any reason why Blazin cant command a 1000 rpm idle speed tempiorarily to keep engine running?

Or leave commanded speed as is and just use the throttle stop screw to up idle to 1000 to allow it to run to temp and hit CL so a BLM read can be made?

Blazin4x4

The idle speed is up bout as far as it'll go... and commanding rpm just hasn't done jack for me.

I think I might be on to something though. I went down to my storage unit mostly to get a little buzz and relax last night but during the cel test I realized that when I did the motor swap I hooked a grouond up wrong and it fried my ecm. I got a good one from the boneyard but IIRC the plug that goes into the ecm had a coulple burnt pin holes... at least it looked like it. Could that be the problem?
Also, I downloaded the .bin off the internet and got one from a member here... Does anyone have a source where I can get a good amur .bin?

Blazin4x4

ttt

anybody?

Binder

Burnt as in electrical short? By all means replace it. What ground did you hook up wrong? Did it do other damage too?

Fast355

iTrader: (2)

No amount of tuning will fix an electrical or mechanical problem.

Attached is a BIN that ran very well in a 76 Corvette L82, which has very similar specifications to your 350. The engine is stock down to the catalytic converter, stock intake manifold, stock air cleaner, etc. The only changes made were to swap on a 454 TBI unit on a 454 TBI-QJet adapter and the CCC HEI setup. Base timing is set at 0* BTDC at the distributer.

Blazin4x4

Wow nice ve table... yeah I just didn't realize/rember about this until a couple nights ago.


Binder: yup like a short. I don't remember what I did it was damn near 2 years ago... hence the frustration.

Once again fast thank you.

Blazin4x4

Think I found my culprit...



Those are the plugs that hook up to the ecm. both are burnt to where I need to repin a whole new plug.

The wire is green where the receptical was crimped to the wire.

I believe I did this when I hooked a frame ground to the starter power.

off to the junkyard

Blazin4x4

Man that was fun... 4 hours to repin those damn things but it's done and now my prom error and est malf flags are gone. Which bring s me to my next question... If I hit the throttle their is absolutley no response but when I let off it's just kickin in. Basically it is REALLY sluggish. Could that be rich, lean or either?

91chevz71

repin...not to threadjack- did you replace the individual terminals that each wire have on the end that plug into the clip? I am trying to figure out what parts I need for hooking up an IAT lead to my existing ECM clip
What are the BLM/INT's like when you were running?
Sounds like it's rich AE maybe. My experience with experimenting w/ AE this weekend did that (hitting a brick wall when I hit the gas) same thing. Too much AE was my prob

Mike

Blazin4x4

no actually I didn't technically repin... I just replaced the recepticals that were burnt in the female plugs (soldered new ones to old wires) and transfered all the good recepticals to a good plug.

my prom error was gone but it still will pop up sometimes after an upload... then it'll go away with a new burn. Is that normal?

My biggest problem though is that my fuel pump won't shut off. I don't know what could cause it to run... even with the key off it will keep going sometimes. Can a brother get some guru troubleshooting?

DENN_SHAH

iTrader: (1)

occasionally i don't get a good burn the first time & have to burn it a second time.

knowing about the problem with the wiring you had, the first place i would look is at the ECM.
it may well be damaged & is causing the fuel pump to stay on.
if the ECM is ok or you swap it out & the pump still stays on some times, next place would be the pump relay, it may stick on intermittently.
if you know the ECM & relay are both good, there maybe a problem with the oil pressure sending unit that powers up the fuel pump in case the relay goes out.
lastly would be a wiring problem somewhere.

Binder

Is your pump wired to the ECM or independent? I used to have mine independent and it would sometimes stay on for a few seconds after shut down. Turned out the relay was being held shut by the votage produced by the spinning of my electric fan. After shut down the fan would be off but spinning down. This produced just enough juice to power the relay that kept the fuel pump on.

Blazin4x4

well I have to pull a fuse to get it to stop... it just runs. I know the fuel pump is wired to the ecm because I pull the ecmb fuse to get it stop.

Okay first off I have a ground cable going from the battery, hooked up to the frame which causes very hard starts.. I just realized this is wrong a few nights ago. So I"ve been jumping it quite a bit. Could that cause a prom error?

Where is the relay and how do I check it?

Also what should I look for in the ecm?



ON a side note the thing runs stronger then it ever has and doesn't die in park, D, or R thanks to fast355's l82 bin... I changed a few things with the iac , spark, and leaned it out which got it decent to the point where I could putt around my storage unit but it's a long way from drivable.


I got some data last night....

I can't remember what is lean or rich though. As far as o2 voltage goes is .350 rich or lean? Also I had one blm value at 145 is that rich or lean?

Do I have to log everything in one run or can I just leave win aldl running and continue it at a later time?

I apologize for the newb questions but in all my troubleshooting I haven't really done any datalogging or tuning.

91chevz71

BLM 145 is pretty lean. O2 voltage of .350 is lean (narrow bandO2).
I've read that Narrow band O2's aren't very accurate AT ALL when not in the 14.7 area (.455 mv).

Blazin4x4

Yeah that what I was afraid of. I leaned it out 30 percent because the thing was PIG rich... well I'll see how it runs if I go back the other way.

vernw

iTrader: (2)

145 BLM is definitely lean, so is .350 O2 voltage. Best way to datalog is to hold various rpm/load combinations for several seconds to get a good reading on what to change and then blend adjacent cells so there is a smooth curve. And as I'm sure you've already heard, a WB is almost a "must have" for WOT tuning, and helps a lot more on the regular driving tune as well. Just my two cents worth.....

91chevz71

Yeah, I think the next purchase for me is a Zeitronix.

vernw

iTrader: (2)

I went with teh Innovate LC-1's for a lot less money and they seem to be working great.

Blazin4x4

Well, a wb was my next priority but I need to get all the bugs out, then I'll go for the wb... right now my fuel pump will stay on even with the key out and the other day it started running all on it's own. The key was off and so was the pump... then WITH THE KEY OFF my fuel pump just started running and wouldn't shut off. To get it too stop I have too pull the ecm fuse which causes another prom error.

I looked over the ecm and it looked good. I also got my ground problem fixed and the pump still won't stop. Only thing that I'm a little worried about is the plug that goes from the laptop to the prominator wouldn't come out of the prominator. Is there a little tab or clip that holds it in or should it just slide out?

Blazin4x4

Can someone tell me how to unplug my prominator? I want to look at the pins and plug to check for burns/ shorts.

If that looks good it's on to the fuel pump relay... but not today... nascar is on

va454ss

iTrader: (1)

By the looks of those ECM connectors, I'd stick an ECM in it.