Hi guys, I usually post over at IROCZONE, but a certain op decided to be an *** and bann me because he felt like it...

anyhoo

I fired up my car for the first time in a month after doing a huge engine mod and heres whats happening.

Idle seems to act normal sometimes, then sometimes it will start at around 2,500 and drop down to idle if I dont touch the gas. Even when its at 800rpm it still sounds like its racing more than it should be. When in park and you give it gas it will sputter, and nothing will happen.

I put the car in drive, and let off the ebrake and it actually squeeld out just letting off the brake, like the motor is racing WAY to high..althought the RPMs seem normal, I dont get it.

I took it for a spin, and it will cruise at 35mph with me not touching the gas, and when i give it gas it either revs up a little bit, or nothing happens and it shuts off/starts back up again real quick. Everytime you hold down the gas to reach speeds of 40+ it will just not run, it shuts off till i let off the gas and it will crank over again soon as i let off.

ONE THING I KNOW WAS WRONG AT THE TIME, I didnt have my EVAP line plugged in to the throttle body, but i realized that and plugged it in, and my b&m switch blew up on me right after i fixed that issue and never had the chance to start it up after pluggin in the evap line but im not sure if that is the problem. (damn b&m went haywire when i was gettin pissed off and bangin on it when it was running bad haha)

i also have a quicktime movie of the car running and what happens if u just give it a little gas if anyone knows where i can host it


instead of saying what I modded I just copied over my specs listed at my cardomain website. p.s. my fuel pressure is at 38psi


Specs:
1989 MAF 5.7

[!] Pro Top Line 200CC aluminum heads
[!] GM .028x4.166 composite head gaskets
[!] Holley Stealthram intake
[!] Holley Stealthram lower manifold
[!] GM Performance "LT4 Hotcam" camshaft
[!] Comp Cams "Pro Magnum" 1.6 rockers
[!] Comp Cams hardened pushrods
[!] Comp Cams valve locks
[!] Comp Cams dual valve springs
[!] Comp Cams titanium valve spring retainers
[!] Comp Cams valve spring shims
[!] Comp Cams flat guideplates
[!] Manley "Race Series" 1.600" exhaust valves
[!] Manley "Race Series" 2.020" intake valves
[!] Hypertech 180 powerstat
[!] Hypertech 180 fan switch
[!] Flow Kooler water pump

Fuel Management
[!] Holley fuel rails
[!] Holley adjustable fuel pressure regulator
[!] Ford SVO #24 fuel injectors
[!] Walboro 255pph in-line fuel pump

Ignition
[!] MSD "Digital 6" ignition
[!] MSD "GM Blaster" Coil
[!] MSD cap
[!] MSD rotor
[!] MSD "superconducter" 8.5mm wires

Transmission
[/] B&M Transmission Cooler 24,000GVW
[/] TransGo Performance shift kit
[/] Corvette transmission servo
[/] Corvette transmission .500 boost valves

Exhaust
[!] SLP 1 3/4" headers (non AIR)
[!] SLP Y pipe
[/] FlowTech exhaust cutout
[!] QTP electronically controlled cutout valve
[/] Flowmaster "American Thunder" exhaust w/80 series muffler

Rear End/Suspension
[/] Borg Warner 9 bolt w/ 3.45's
[!] Spohn Sub Frame Connectors

Nitrous Oxide
[/] N.O.S. 100/150 adjustable TPI kit
[/] N.O.S. purge valve kit

Other Modifications
[!] A/C removed, pulley put in place
[/] Steel hood switched to fiberglass
[/] K&N air filters
[/] A.I.R. stripped from car
[/] Catalytic converter removed
[/] T.B. coolant line bypassed
[/] Gutted air boxes



the ones with [!] are mods I just completed yesterday....took me a month for everything to swap over.


Yzingermotoman on AIM

 

lets have this quick time movie...

 

Sounds like a classic vacuum leak. A pretty big one.

 

Or maybe your IAC valve (on the bottom of the throttle body) is just shot or the plug to it has become disconnected/damaged. Other than a vacuum leak causing a high idle the IAC is the way the ECM controls idle speed. Sometimes they "freeze" in one position- sometimes open, sometimes closed, and you get an abnormally high or low idle speed.

 

I agree, Sounds vaccuum related, High idle, poor drivabilty.

 

Never owned a TPI car, but I though they were supposed to take like 45 psi fuel pressure. Especially with nitrous.