Hive

I have finnally managed to setup my fuel map. Car was working perfectlly for a day or two and then it started to lean out badly in low RPM range (1000-2800 RPM) which would stop as soon as I would press the gas pedal more than 45%. We have figured it out that since we have put in larger injectors (650 cc instead of 210 cc) fuel pressure should be raised more than 3.0 bar to compensate for larger injectors. After we have done that car started to work as a baby again.

Well, problems started again after I have turned the AC on. As soon as I turn the AC on I start leaning out in the low RPM range (and it is leaning badly - 28-30 AFR). Should I raise the fuel pressure again to compensate that or would it be better to increase fuel delivery through the fuel map?

Also sometimes when I press the clutch my RPM's drop down very low (to the point where car almost dies) and then back to 1200 RPM and continue to shift between 350 RPM to 1000 RPM for a minute or two before it gets steady at around 800 RPM. Would adjusting the fuel map in low RPM range (currently I am subtracting -64% of fuel through fuel map to compensate large injectors) and adding more fuel there solve this problem?(e.g. instead of subtracting 64% should I subtract lets say 60%)

Last problem that annoys me a bit is AFR values which I get if I leave the car working in neutral for a several minutes. In first two-three minutes AFR is almost ideal 14.7 but then it just starts to richen up and it gets to around 10.7 AFR. Any way to solve this?

Does anybody have any ideas? One I got from the AEM forums is that I might have a boost/vacuum leak but to be honest I do not know where to start checking since I do no thave any problems getting full boost (1.2 bar - cca. 17.5 psi)

Here is my Fuel map:

CJtheFatty

Get a vacuum tester. Can get a cheap one at Harbor Freight or an expensive one at a car parts place. Sounds exactly like a vacuum problem.

SOCKS_old

when its showing lean at low rpm? is it bogging at all? how about when you add a little throttle?

did you do the injector scaling, or just adjust the fuel map based on the ratio of bigger/smaller injectors?

what in/hg of vacuum are you pulling at idle? should be 20+ or so.

try doing the injector scaling, where it does it automatically: before inj. 210cc = after inj. 650cc and itll automatically scale it.

at least try it once and see how it compares to the fuel map you created.

what is your fuel pressure set at right now? and why are you messing with it from what it should be stock?

Hive

^^Immediatelly after I put it into the second gear and the RPM's are below 1800-2000 it is showing lean and it starts bogging. Same condition emerges in third and fourth gear if the trottle is pressed for less than 35% and the RPM's are below 2000 RPM. Bogging (and leaning also) stops as soon as I add throttle (throttle pedal around 35% pressed) and if I keep it pressed aorund 35% or more there is no problem with bogging or leaning. I can also get full boost without any problem and without leaning. I wouldlike to point put that leaning out and bogging without AC on have stopped after we have raised the fuel pressure to 3.5 bar. But as soon as I turn the AC on i lose fuel pressure again and car is leaning and bogging. Car even shuts down sometimes if the bogging is "to violent" and leaning out extreme (it leaned to 30AFR several times). Also I have no problems with the car (except unsteady RPM's if I press the clutch fast, but it gets to normal after a minute or two) if the AC is not turned on. No bogging or leanign then.

I did use injector scaling that was the first step before adjusting the fuel map to meet demands.

Not sure about vacum at idle but will check it tomorrow.

Fuel pressure is currently set at 3.5 bar. It was set to 3.5 bar also when I had stock injectors inside but the fuel pressure dropped to 2.8 after 650 cc injectors were put in and the car was almost unusable in low RPM range (but it was working fine with more than 35% throttle).

2 CJtheFatty: unfortunatelly I cant get my hands on vacuum tester here in Croatia and it would take at least 10 days to get it from the US. Any other way to test the vacuum leaks?

SOCKS_old

is there a TPS setting on the FIC that you have to calibrate?

if so, i had almost the same issue it sounds like your having with it showing LEAN on the wideband and terrible bogging, it was because my emanage wasn't recognizing the TPS. i calibrated it with the emanage, and voila, fixed. not sure if its the same issue, but its possible.

a vacuum leak could also cause most of your problems.. with fuel pressure, leaning, and bogging.

Hive

If I remeber correctly only RPM needs to be calibrated.

Stocker

I dunno about the maps, but it sounds like you have a problem with your car ONLY when you turn on the A/C.

When the A/C kicks on, what happens to the voltage at the fuel pump? Measure directly at the pump . . .

Hive

Yes I thought about that but I had same problems without AC before I have raised the pressure at FPR.

ScoupeLS

there is a tps calibration.

Bullfrog

You did notice he's from Zagreb, Croatia right? That's in Europe, eastern Europe. Some people take offense when they are though of as just another American, but Hive has been around for a while. I don't think they have harbor freight over there...

I do agree to get a vacuum tester though.