Hey guys, I am having one hell of a hard time trying to get this 2003 cavy to run. I am trying to fake a 2 bar MAP in this thing and for the life of me it will not run and I have no clue as to why. The car is a customers car and it's a 2003 cavy with the eco. I installed the Saab turbo setup for him last week and now I am trying to get it to run! I have done 2 and 3 bar fake tunes before with absolutely no issues, but this car is making me want to shoot things. I need some help or some suggestions as to where to go from here, I have some idea's but I am starting to grasp at straws now and since this is a customers car I would like to get it back to him asap.

Here is what I have done so far. Went through his stock file and changed all the tables that have to be changed for a fake 2/3 bar map (Hi Octane Spark, Low Octane Spark, PE Hi Octane spark, PE Low Octane Spark, Base Idle Spark, IAT spark, ECT Spark, Launch Spark, and MAP min value). I am also using an old style 2 bar MAP sensor with the old pigtail that I wired in color for color (this might be my issue but I am not sure as I can't seem to find a wiring diagram for a 2003 and nothing is turning up when I search this site for it). When you try to start the car it will start and run fine for about 2 seconds and then it falls on it's face and dies. When it first starts the MAP reads fine at about 20KPA but when it starts to die the map comes up into the 40's before it dies. The MAP sensor just sitting at atmospheric pressure reads 54KPA which would be about right on a 2 bar sensor. At first I thought it might be a vacuum leak somewhere but with the old one bar sensor connected the car idles perfectly. As far as the PCM goes I have dug pretty deep into it. I changed the VIN in this car to match Andy's file (same year sunfire that I tuned a 2 and 3 bar setup on) and then uploaded Andy's file to his car. Went through the security learn process and when I fired the car it did the exact same thing. I used Andy's old 2 bar tune so in therory it should of fired up and ran with no issues since both cars are the exact same years. Now one thing I was able to track down is that Andy's PCM never had the PCM recall in 2004 to be reflashed, the car that I am working on right now had it done. I am now wondering if it was encrypted and some of my changes are not taking effect?

Now here is the strange part of things that is really throwing me for a loop. If you unplug the harness connector from the MAP the car will sit and idle all day long and run pretty good, same happens if you unplug the vacuum from the MAP sensor. When this is done everything on the scanner shows pretty good with the exception of the O2's being very rich (950mv's) which is understandable because with no connection at the MAP it is going to want to add fuel (54KPA on the MAP). Now if I plug either the electrical connector or the vacuum line back in the car dies right away, doesn't even try to stay running. I can keep it running if I play with the throtle but just barely and it runs like a bag of hammers. One thing I did notice though was that when the MAP is connected the 02's readings are not correct. The 02 sits around 451-452 and doesn't move from there yet the wide band is showing 11.6:1 (although it is an innovate wide band and I am not certian that it is accurate (for future reference don't buy this wideband, waste of time compared to the rest on the market)) and you can see that it is running very rich by the black smoke out the tail pipe. You unplug the MAP and O2's return to normal in the scanner. I am now wondering if there is a problem with the way I have the MAP wired into the car. I am wondering if somehow the MAP and new connector are stealing a ground from the O2 sensor which would explain why the O2 readings are not right when you try to connect the new MAP. I have searched everywhere for a wiring diagram for this car and can't find one anywhere, even my shop program doesn't have it. So there you have it, if anyone has any suggestions at all I am all ears.



Edited 1 time(s). Last edited Friday, July 18, 2008 5:25 AM


Quoth the Raven 'Nevermore
raven@accesswave.ca
Raven Autosports
55 McQuade Lake Cres,
Halifax, Nova Scotia, Canada
(902) 850-3330
10.82@132

Do you have a wideband connected to it currently? If so what are the AFR's on it? The J's use map reading for fuel at idle, so using the 2 bar map sensor is throwing things off. I had this happen on a 99 Z24 we installed the GM charger on. When we hooked up the 2 bar map it was ran like crap until I tuned the fuel. My guess is fuel at idle. It is really idling at one KPA but getting fuel for a different KPA because of the 2 bar map.



FU Tuning

Yeah I do have a wide band and it is showing 11.6 ish when running (with or without the MAP connected so I am really not sure if it is correct or not), but that should still be able to run though. I have seen plenty of cars that will idle at 10:1, granted lots of black smoke but still run. It also doesn't explain why my O2 readings go to hell once the MAP is connected (O2 should be moving constantly and with the black smoke it should be a high number (900+mvs) but it's not, it sits around 450 which to me says there is either something wrong with the sensor or the wiring. This car also won't run at all with the new MAP, not even for 3 seconds. Even with a very rich idle table it still should be able to run. I tried pulling a tone of fuel from the idle and low RPM tables and it did nothing, same result.



Quoth the Raven 'Nevermore
raven@accesswave.ca
Raven Autosports
55 McQuade Lake Cres,
Halifax, Nova Scotia, Canada
(902) 850-3330
10.82@132

1st check the obvious. I had the same situation, Car would start up run and would then go pig rich and idle any adjustments to the table would result in the same problem. Figured it to be the tune and was messin with it all day before I Tracked the problem down to the ground wire on the back of head to the left side of the head i believe that is where it goes. Check to make sure that and other grounds are good unless you didn't touch any on the turbo install.

I had basically all of the same symptoms you've listed above.

I am starting to think it is a wiring issue as well. The thing is that when I pulled it in (turbo was on the car but still had the one bar installed and the stock file) it ran fine, no issues at all. I wired in the new MAP sensor, changed the tune and all the problems started. There is only three wires out of the MAP and as far as I can tell it is wired right. Pin A on the connector is the org/blk wire, Pin B is Ltgr/blk and PIN C is gray. I am kind of thinking a ground issue but I haven't done anything other than wire in the new MAP and make some changes to the PCM. I am still at it now, just tried switching pin A with Pin B at the map connector to make sure but again it does the same thing. And the thing is this car will not Idle...at all!!! If the MAP is connected it starts and the dies right away. It is wired back to the way I had it now so I will keep looking.



Edited 1 time(s). Last edited Friday, July 18, 2008 7:14 AM


Quoth the Raven 'Nevermore
raven@accesswave.ca
Raven Autosports
55 McQuade Lake Cres,
Halifax, Nova Scotia, Canada
(902) 850-3330
10.82@132

if you need me to look anything up let me know i have the GM Service Information. What you had for the map it showed too on SI


JBO since July 30, 2001

I actually have the exact same problem trying to get my 3 bar working with HPtuners, (i know you've heard that before) But yeah, it idles for about 2 seconds then dies. Consistently, but the 1 bar will work fine on the same wires. I wish I could help, but i honestly haven't figured this one out yet. So hopefully the solution will relieve both our troubles, however my car is a 99, so the solution may not be the same. ( I dont know much about eco's) For mine I have to switch the harness to work with the new map sensor, so I use the green GM three prong one. Is it the same deal? What Map sensor do you use?

Quote:


Went through his stock file and changed all the tables that have to be changed for a fake 2/3 bar map (Hi Octane Spark, Low Octane Spark, PE Hi Octane spark, PE Low Octane Spark, Base Idle Spark, IAT spark, ECT Spark, Launch Spark, and MAP min value).

Take a look at the idle VE and low RPM VE tables, most of the ones i've seen are MAP based, and it looks like you skipped over them.





4cyltuner.com - Information Source For 4 Cylinder Tuners
Buy stuff from CarCustoms Ebay! Won't be disappointed!

Shifted wrote:

Quote:


Went through his stock file and changed all the tables that have to be changed for a fake 2/3 bar map (Hi Octane Spark, Low Octane Spark, PE Hi Octane spark, PE Low Octane Spark, Base Idle Spark, IAT spark, ECT Spark, Launch Spark, and MAP min value).

Take a look at the idle VE and low RPM VE tables, most of the ones i've seen are MAP based, and it looks like you skipped over them.

If this works I will fly out there and kiss you, lol.

With Andy's car I didn't touch those tables at first, his car was already running very rich so it didn't really matter. I just backed everything down from there but I didn't scale them originally. I did just add 40% to the VE offset and it now idles for about 20 sec with good scan results till it does the samething and then stalls out. I am going to go back through and rescale those VE tables and see what happens. Thanks.



Quoth the Raven 'Nevermore
raven@accesswave.ca
Raven Autosports
55 McQuade Lake Cres,
Halifax, Nova Scotia, Canada
(902) 850-3330
10.82@132

ok I looked back through and there was two tables that do reference the MAP (Idle and coastdown). I rescaled both tables and now it looks like I have a theift issue, lol. I am still using Andy's file and last night when I did the relearn I only had to do it two cycles and it fired up when normally you have to do three. I am doing the relearn procedure now and then I will see what happens.



Quoth the Raven 'Nevermore
raven@accesswave.ca
Raven Autosports
55 McQuade Lake Cres,
Halifax, Nova Scotia, Canada
(902) 850-3330
10.82@132

Well that didn't work out very well, I rescaled those tables and I'm still getting the same results. The only positive thing that I did was two changes ago when I bumped the VE offset uptoo 40% it ran for about 20 sec before dieing out. One thing I didn't mention was that I am still using the stock injectors (going to swap out for larger but they are not here yet). The inj setting are untouched due to this and I can't really see them being an issue as to why the car won't run. Going to keep plugging away at it to see if I can figure this thing out.



Quoth the Raven 'Nevermore
raven@accesswave.ca
Raven Autosports
55 McQuade Lake Cres,
Halifax, Nova Scotia, Canada
(902) 850-3330
10.82@132

I had this issue on an Eco too, it just wouldn't run after reflashing until it was driven around for about 30 minutes, then all was fine.





4cyltuner.com - Information Source For 4 Cylinder Tuners
Buy stuff from CarCustoms Ebay! Won't be disappointed!

I gave Raven a call... couldn't explain this stuff over the interweeb the way I want but he's going to try some things and get back to us.

He DID get the car running with the idle ve table raped at 40% offset so the computer wants fuel.... which leads us in the right direction.

Pretty sure all the info I gave ya will point you in the right direction James! Let us know how it goes!

Just so you all know...

I advised him to:

- Put the idle VE table to stock.. for some reason it does NOT read in 2 bar when faked.
- Undo the 40% offset on the VE tables and put it back to stock.
- Raise the injector constant size around 40-44% and go from there... for some reason the constant needs to go up. Anybody that wonders why you need to do this: view the Stock LD9 table and the GMSC table. Injector constant N/A is 2.0250 and the new 2 bar tune with BIGGER injectors (Constant should go DOWN) is 2.6xxxx.... This didn't make sense to me for a long time until I tried a fake 2 bar.
- The car is hesitating and the car is going heavily lean on the wideband when he blips the throttle right now... I told him to view his faked 2 bar low RPM timing tables... I'm dead sure that in the faking of the 2 bar it's overlooked that the timing down low at idle is affected by squishing the chart. Commanding 5 degrees of timing at 1000rpm @ 30 kpa isn't going to give anybody good throttle response! lol
- Be sure to copy all modified tables to the alcohol tables. For some reason those stupid tables are referenced! So don't forget to change them to match everything else.


I hope that helps anybody that tries this one day.

I'm no expert / professional tuner I just went through all of these same issues when I faked my 2 bar a month ago. Getting the car running is actually the hardest part, surprisingly.

I haven't been able to work on mine due to the car being down... but I hope to get back at it after the bash. (For those of you who are waiting on my LD9 fake)

-Chris-


-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...