SC300_704

iTrader: (5)

my car is a 93 SC300 w/ 550cc injectors, turbonetics 60-1 and supporting mods. also running the map ecu IAT as well. anyways i'm currently running the 525cc map that i found on the map ecu forum, my question is some days it will start and run perfectly fine for normal driving but really rich at WOT. but if i were to turn off the car for about 15-20 minutes and try to start it up again it won't start unless i keep cranking it for about 5-10 times. and most of the time when i'm trying to start it up it will run for like 1 second then dies again. and when it does start it wouldn't go past 3k rpms and if i try to go past it, it will die on me. a lot of times it will let me go past 3k rpms but like i said some days it runs fine but some days it runs like crap. i know i need a professional tune but i'm still saving for it.

SC300_704

iTrader: (5)

i had the IAT in the center of the red circle b/c i was reading a thread here on CL that this was the right place to put it but now i'm having second thoughts about it. b/c when it's cool outside or my engine is cold it'll run perfect but once it starts to get hot the it'll start acting up. what should the temp. be showing on the dashboard on map cal, mines show up to 110+ degree F? and as for the jumpers i'm not sure on that yet, i'll have to find the correct tool first. also i'm not running the stock o2, only the lc1 wideband.

attzor

iTrader: (1)

I was having a similar issue, the car would run, die, and have trouble restarting, it was a combination of the EFI relay and a bad battery, after replacing the battery, it wouldn't die, but if the car was turned off after running, it wouldn't turn over for a few minutes, later I figured out that I needed to pull out the EFI relay and blow on it N64 style, which fixed it and now it doesn't do it anymore. My car isn't an NA-t but it is turbo and it is using MAP-ECU2.

In short, next time it won't start, pull out the big round EFI relay under the hood and make sure its clean, then push it down snug, get it in there good.

SC300_704

iTrader: (5)

i just did the 12v mod and it kinda fixed it but not all of it. if the car is running and i turn it off and and try to turn back on right away, it won't turn on until the 2nd try. btw is it normal for the fuel pump still running for about 2-3 seconds after i've taken the key out when doing the 12v mod, i'm running the walbro 255 btw? also it doesn't die when i go past 3k rpms anymore or at least for now..i'll have to drive it more to really know. where did you put your iat?

attzor

iTrader: (1)

I'm pretty sure I don't have that wired up, theres no sensors in my IC system, nor in the intake manifold. It's normal for the pump to stay on for a few seconds, mine does, and I have the 12v mod done. Check that EFI relay when it's doing it, also check the coil packs and igniter module.

SC300_704

iTrader: (5)

well took it for a drive today and like i said before it ran fine but once the temp. got hot (110+ degrees) in the engine bay it will fall on it's face. now my next step is to relocate the IAT to a cooler place and hope that fix my problem.

SC300_704

iTrader: (5)

tried disabling the IAT compensation but it's still doing the same thing and this time it was only showing about 93-98 degree F...maybe it's not the IAT?

hyjaxx

iTrader: (1)

Did you set the MAP2 to recognize the Wideband or Standard O2 as the primary signal? I had the LC1 wired as primary and had the same issue. Once I re-did it to read off the standard o2's it worked fine. Are you throwing any CL's?

shonuff53

iTrader: (3)

list of checks
did you configure the ignition inside the box
get rid of IAT
disconnect your factory o2(s) from the factory ecu its ok to keep it to the mapecu2
reset battery
look at o2 readings from wideband and make some good adjustments or just datalog the sucker

this is just for the mapecu2, I have no idea if you might have car issues so im just saying.

shonuff53

iTrader: (3)

whens the last time you checked your plugs, if its been a while maybe you should change them out check your gaps.

shonuff53

iTrader: (3)

ok nevermind about the plugs, whens the last time you changed your fuel filter, and do you have a fuel psi gauge hows it looking?

SC300_704

iTrader: (5)

i have it to read my LC1 and currently not running any stock o2's. but that makes me think..when i first got the car running, i was running stock o2 but the car ran like crap especially during take off at a red light etc. so the guy from map ecu forums told me to disconnect it and pull the EFI fuse for 30 seconds or so and i just never connected it ever since...
am i supposed to set the jumpers j3 to high and j4 to positive? i'm currently running the IAT that came w/ the map ecu2 but have installed a 10K resistor instead of the 2200 ohm resistor into the stock MAF/IAT plug (maybe that can be the problem?). pulled the EFI fuse about a million times lol. and me and buddy have been trying to street tune it but it keeps dying
actually the plugs that i'm running are denso ik27 which are pregapped at .030 iirc. i have a new fuel filter but have not installed it yet and i don't have a fuel psi gauge.

SC300_704

iTrader: (5)

i was told a bad coolant temp sensor can cause this kind of start up problem as well..any ideas?

shonuff53

iTrader: (3)

set your iat back to factory setup, take off the mapecu2 iat. I dont know what your configuration is supposed to be like on the ignition but just look it up. and disconnect the o2 from your car's ecu if you havent done so and try retunning and driving. Im not sure about the coolant temp sensor, quick easy check for your coolant if you have a wideband is just turn the car on from a cold start it will run richer on start up then look to see if your air/fuel starts to lean up a little after you reach warm up temp.

shonuff53

iTrader: (3)

*If you leave the o2 hooked up your cars ecu will adjust almost instantly while driving ruining your tune on the mapecu2, you can run it like this fine Ive been doing it for 2 1/2 years the tune will stay put...thats why i say disconnect it*