just finished putting it all together

bottom end is built Je pistons eagle rods ect ect.
head jdm b16 with gsr cams


Now I go to start it up, it wont stay running unless Im holding down the gas a little. There is an idle surge, and just stalls out if i let off the pedal.
Ive been building these things for awhile but this I just cant figure out

Idle air control is fine
TPS is fine
aftermarket 3bar map sensor, so thats fine
no check engine codes.
timing is right on
all vacuum is connected


anybody have any ideas to solve the issue??


Modified by eVo05 at 10:57 AM 7/12/2007

 

what ecu and if it's surging most likely there is either some air gaps in the cooling system or a vacuum leak, typically at the throttle body gasket or intake manifold flange.

also, make sure that the idle screw is not tightened all the way. if there is some sort of coating on the screw, like an epoxy, then leave it- it's fine.

what happens when you unplug the IACV and start it up? or, unplug the IACV while it's idling?

 

chipped p28 with chrome ecu software

There are probably air gaps in the system, but It wont stay running so it makes it even harder to get them out. Ill check the gaskets again, but i tried that already and there was no leaks

 

idle screw I backed out a little, just to see if that was it, It def is running richer than what it should be. I had 660cc injectors in it before hand, but it was even more difficult to get started. Aleast with the stock 1's I can get it to run I tried playing with the iacv hasnt really changed anything other than a cel


Modified by eVo05 at 11:33 AM 7/12/2007

 

so it still surges with the IACV unplugged? if so, there is def a vacuum leak somewhere...

typically it should just dump down to a low but steady idle when the IACV is unplugged.

i wonder if the maps are just too rich for the setup? what bin/tune is on the ECU right now? you might need to start from the ground up with the maps, but i'd imagine with a p28 w/ stock, say, gsr bin and stock injectors you should be able to get it to idle so you can bleed coolant, etc, but of course at the dyno you'd want the big injectors in...

well, good luck man!

 

yea it still surged, I wonder where tho, all the lines are new!! I just had another map burned on it, to account for the 660's, its def not a tuning issue..I just cant get it to idle steady without touch the gas pedal a touch..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by eVo05 &raquo;</TD></TR><TR><TD CLASS="quote">yea it still surged, I wonder where tho, all the lines are new!! I just had another map burned on it, to account for the 660's, its def not a tuning issue..I just cant get it to idle steady without touch the gas pedal a touch..</TD></TR></TABLE>

first culprit is usually the TB gasket, second is intake mani gasket. what gaskets are you running in those spots and were they new?

you can take carb cleaner with a tube on the nozzle and spray around the flanges of the intake mani and TB. it's possible that you could find the leak that way because it will suck in the carb cleaner and the idle will change as soon as you hit the spot.

 

gaskets were new last build, 6 months ago, but i never took them off, nor apart. I tried finding vacuum leaks with no luck, also It wont rev past 2500-2700 rpm's starts to back fire and stuff, Timing is dead on I checked it again and re did it anyways. Could it be my distributor?? computer?? Nobody else has any suggestions?