Idle problem.... please help!
#1
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Car: 1986 Trans Am, 1991 Firebird
Engine: 355 TPI, 3.1L V6
Transmission: 700R4 in both
Idle problem.... please help!
New engine.... just started about 3 nights ago. Cams broken in, oils changed. Timing is set to 6* (in drive). Problem I'm having is... the car idles in park at about 950rpms but will not idle in any gear. Now the proper way to set the idle air control is to unhook the IAC and set the idle to 450rpms according to the tech article. I doubt very seriously if I could get my car to even try and idle at 450rpms. Fuel pressure is set at about 40psi and you can see my mods in my signature. Do you think my car needs more than 6* timing(in park) and that's why it won't idle in gear? Please help.
------------------
1986 Trans AM
355 TPI
4 Wheel Disc Brakes
9 bolt Borg Warner Rear (2.77's....oh joy) :P
6" rods, approx. 9.7:1 Compression, Stock TPI (soon to be ported), 24#/hr LTI injectors (cleaned and flowmatched by Cruizin Performance), Hedman Shorty Headers, 3" exhaust with 80 series flowmaster, SBC 993 heads completely redone and modified for 1.6 RR, 1.52 RR (for now), Comp Cams XE262-14 TPI Cam, Holley AFPR, TPIS airfoil, MSD wires, MSD 6-AL Ignition, Hypertech 53,000 volt coil.
Track times to come.
------------------
1986 Trans AM
355 TPI
4 Wheel Disc Brakes
9 bolt Borg Warner Rear (2.77's....oh joy) :P
6" rods, approx. 9.7:1 Compression, Stock TPI (soon to be ported), 24#/hr LTI injectors (cleaned and flowmatched by Cruizin Performance), Hedman Shorty Headers, 3" exhaust with 80 series flowmaster, SBC 993 heads completely redone and modified for 1.6 RR, 1.52 RR (for now), Comp Cams XE262-14 TPI Cam, Holley AFPR, TPIS airfoil, MSD wires, MSD 6-AL Ignition, Hypertech 53,000 volt coil.
Track times to come.
#2
who did your chip?
they usually perscribe timing setting.
access a scanner for your system.
IAC position should be between 40-60 idle..
because of the cam. the IAC will be higher.
TPS voltage is?? .5-.7v idle any higher system
tends to run faster idles.
vacuum leak?? TPI gaskets are a pain for vacuum
leaks. disable the MSD and retime. some have
reported dying and low idles while trying
to time the engine and seem to short themselves
proper timing.
somethings to look for.
airdeano
they usually perscribe timing setting.
access a scanner for your system.
IAC position should be between 40-60 idle..
because of the cam. the IAC will be higher.
TPS voltage is?? .5-.7v idle any higher system
tends to run faster idles.
vacuum leak?? TPI gaskets are a pain for vacuum
leaks. disable the MSD and retime. some have
reported dying and low idles while trying
to time the engine and seem to short themselves
proper timing.
somethings to look for.
airdeano
#3
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Car: 1986 Trans Am, 1991 Firebird
Engine: 355 TPI, 3.1L V6
Transmission: 700R4 in both
<font face="Verdana, Arial" size="2">Originally posted by airdeano:
who did your chip?
they usually perscribe timing setting.
access a scanner for your system.
IAC position should be between 40-60 idle..
because of the cam. the IAC will be higher.
TPS voltage is?? .5-.7v idle any higher system
tends to run faster idles.
vacuum leak?? TPI gaskets are a pain for vacuum
leaks. disable the MSD and retime. some have
reported dying and low idles while trying
to time the engine and seem to short themselves
proper timing.
somethings to look for.
airdeano</font>
who did your chip?
they usually perscribe timing setting.
access a scanner for your system.
IAC position should be between 40-60 idle..
because of the cam. the IAC will be higher.
TPS voltage is?? .5-.7v idle any higher system
tends to run faster idles.
vacuum leak?? TPI gaskets are a pain for vacuum
leaks. disable the MSD and retime. some have
reported dying and low idles while trying
to time the engine and seem to short themselves
proper timing.
somethings to look for.
airdeano</font>
I haven't checked the IAC yet
TPS voltage was fine last I checked, may need to check again.
I don't know about vacuum leaks. I have all new gaskets on the TPI system.
MSD and Hot coil are currently not hooked up... I'm adding these after the car is running properly.
I think I'm going to try bumping the idle and then checking the IAC. I might also try bumping the timing to 8* but I'm trying not to go too high on the timing until I get my exhaust done because there's no way I could hear audible knock over the exhaust right now.
------------------
1986 Trans AM
355 TPI
4 Wheel Disc Brakes
9 bolt Borg Warner Rear (2.77's....oh joy) :P
6" rods, approx. 9.7:1 Compression, Stock TPI (soon to be ported), 24#/hr LTI injectors (cleaned and flowmatched by Cruizin Performance), Hedman Shorty Headers, 3" exhaust with 80 series flowmaster, SBC 993 heads completely redone and modified for 1.6 RR, 1.52 RR (for now), Comp Cams XE262-14 TPI Cam, Holley AFPR, TPIS airfoil, MSD wires, MSD 6-AL Ignition, Hypertech 53,000 volt coil.
Track times to come.
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