need help from keeping my rebuilt motor from dying...
#1
need help from keeping my rebuilt motor from dying...
ok guys, i got my newly rebuilt streetported engine started twice but it's very hard hard to keep a steady idle. it dies out when i let my foot off the gas and the rpms fall really fast which could be attributed to my 9.5 lb flywheel. what screw(s) can i adjust to keep it from dying? I also have a pfc with base mod map which i will use to break in the motor. My mods are all the bolt ons with full non sequential twins. thanks in advance.
#2
Constant threat
I've got a healthy streetport on my engine too, but it started up and purred like a hungry ***** when I first fired it up. I am sure your light flywheel doesn't help, but it sounds like you have a LOT more going on there....
How are your injectors and all that? What ECU are you running?
How are your injectors and all that? What ECU are you running?
#4
HAHA V8
iTrader: (9)
Originally Posted by RX7 RAGE
hi, ive got an apex power fc with base mod map. my vta1 value is .80 and my vta2 value is 1.79. would these tps figures cause the dying? i've got 1300cc secondaries but i changed the figure on the commander to reflect that.
#5
Original Gangster/Rotary!
iTrader: (213)
As per page F-182 in the FSM:
narrow range---fully closed, 0.75 to 1.25V//closed to open, 1.0 to 5.0V//fully open, 4.8 to 5.0V
full range---fully closed, 0.1 to 0.7V//closed to open, 0.4 to 4.3V//fully open 4.2 to 4.6V
(I think VTA1 is narrow range and VTA2 is full range on the pfc commander, but without having it in front me I can't be sure.)
You want to check all of this with the motor warmed up, but shut off. Have the key in the 'accessory' position, and rotate the linkage by hand. Also, you'll want to reset the ecu by disconnecting the ground on the battery for at least 20 seconds and depressing the brake pedal.
narrow range---fully closed, 0.75 to 1.25V//closed to open, 1.0 to 5.0V//fully open, 4.8 to 5.0V
full range---fully closed, 0.1 to 0.7V//closed to open, 0.4 to 4.3V//fully open 4.2 to 4.6V
(I think VTA1 is narrow range and VTA2 is full range on the pfc commander, but without having it in front me I can't be sure.)
You want to check all of this with the motor warmed up, but shut off. Have the key in the 'accessory' position, and rotate the linkage by hand. Also, you'll want to reset the ecu by disconnecting the ground on the battery for at least 20 seconds and depressing the brake pedal.
#6
In the burnout box...
iTrader: (32)
should have nothing to do with the flywheel. my 8.5lb has never even caused me to stall out. it must be either a vac leak or some sort of fuel problem. if you havent adjusted your tps and your car ran properly before the motor swap do not touch your tps! i adjusted mine to the specs and it acually runs consideralbly worse. i would have someone look over the map and in the free time look for vac leaks. does the car at least stay running if you get it to 1500-2k?
#7
development
Rich is right, make sure your TPS is calibrated...with your engine being in and out.
but to answer your question, there is an idle screw on the front of the TB, that you can tighten to allow more air to seep past the primary butterfly (IIRC)...you will notice the screw pushes down on the linkage the throttle cable connects to.
Originally Posted by RX7 RAGE
what screw(s) can i adjust to keep it from dying?
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#10
Originally Posted by RTS3GEN
tps or idle adjust screw under the throttle body!
#11
Goodfalla Engine Complete
iTrader: (28)
I have seen this happen on a 2nd gen when my buddy installed his lightweight flywheel. stock ECU and he also installed the RB full exhaust (engine back, true dual) along with an intake of some sort from RB. It would die out if he didn't leave it in gear as he came to a stop. if he let it fall from high rpm, it would stall out.
#12
development
yep...especially when changing TB's, the TPS must be calibrated. Your ECU and MAP aren't on the same team yet
should be everything you need to know
Originally Posted by dubulup
should be everything you need to know
#13
In the burnout box...
iTrader: (32)
^ i know you are much smarter than i am... yet if he had the pfc and the tps sensor has not been messed with and the car ran properly before i would not move it. the air bleed screw can be adjusted to help with idle. and he might want to reset his idle via the cable. i had references that were slightly out of spec and the car ran quite well... not perfect but it ran well. i then adjusted the tps to be within specs and the car runs worse now. i guess if the specs are way out then change it but i would write down your specs you have before you change it so you can go back.
i honestly think theres a massive vaccume leak somewhere that is causing it to die right out. if he can get it to stay running at an rpm i would use some carb cleaner to check for vac leaks. or just check for some vac lines that are not connected. some motors dont have to good compression on startup so any leak is not going to help. my 3mm motor took a lil while to start up.
if he has or can get his hands on a commander unit its very easy to check the tps specs which is what i would recommend. and the tip for not stripping the tps screws is to just take the throttle body itself off and loosen them up.
i do not disagree that the tps is the problem i just dont want him to have the same scenario i had. i hope he has a quick fix with the tps calibration. but please before you adjust it just probe the connector and write down your specs so you can go back.
-Lance
i honestly think theres a massive vaccume leak somewhere that is causing it to die right out. if he can get it to stay running at an rpm i would use some carb cleaner to check for vac leaks. or just check for some vac lines that are not connected. some motors dont have to good compression on startup so any leak is not going to help. my 3mm motor took a lil while to start up.
if he has or can get his hands on a commander unit its very easy to check the tps specs which is what i would recommend. and the tip for not stripping the tps screws is to just take the throttle body itself off and loosen them up.
i do not disagree that the tps is the problem i just dont want him to have the same scenario i had. i hope he has a quick fix with the tps calibration. but please before you adjust it just probe the connector and write down your specs so you can go back.
-Lance
#14
development
Originally Posted by RX7 RAGE
I actually transfered my TPS to a polished TB.
Originally Posted by mono4lamar
yet if he had the pfc and the tps sensor has not been messed with and the car ran properly before i would not move it.
and a vacuum leak would mean more air passed the throttle plates...increasing idle rpm. not stalling the car.
#15
In the burnout box...
iTrader: (32)
^ good one didn't see that with the tb. your absolutely right! another thing i thought of. did you change map sensors? i did not switch my settings (i forget which option) for the map sensor and it would cause the car to die if i let off the throttle.
the simplest thing at this point would be to adjust your tps and have the air screw closed at first. its normal to turn it a little bit afterward to clear up problems.
from this point forward i will not contribute misleading information
the simplest thing at this point would be to adjust your tps and have the air screw closed at first. its normal to turn it a little bit afterward to clear up problems.
from this point forward i will not contribute misleading information