30lb/hr injectors in.....too rich at idle, help!

84LX89GT · 04-20-2003, 10:44 PM

Ok, i installed some 30lb/hr injectors, Ford Racing 70mm MAF (for injectors) and a walbro 255lph pump the other day (in preperation for running nitrous). Anyway, now the thing runs too rich at idle (floods engine), at all other speeds it runs fine. I reset the fuel pressure to 35psi key on from 42 psi and it seems to run a bit better at times, but it still doesn't like to idle.
My question is, what should i tinker with to get this thing to idle? Should i reset the throttle blade more open and lower TP voltage (but make sure it shows WOT at full throttle)? Would an idle adjuster work? I know 30 lb injectors and 255lph fuel pump is way overkill for regular driving, but i just want to be able to drive from the track and back without it dying at stoplights.
All ideas are greatly appreciated.

84LX89GT · 04-20-2003, 10:47 PM

Oh, and just so it's in the clear, i double checked that all vacuum lines are connected and sprayed brake clean around all gaskets and vacuum lines and my vacuum gauge shows the same vacuum (19in) that it had before the install.

04-20-2003, 11:56 PM

Clear the computers memory by disconnecting the battery for about 20 minutes.

Disconnect the Idle air bypass solonoid
Reconnect battery

Start engine and set idle speed to desired RPM with stop screw on your throttle body

Turn off engine and reconnect the air bypass solenoid

set TPS to 0.90 - 0.95 volts (Don't go over 1.0 volts Use a digital volt meter when yoiu set this
Start engine and let it idle for 2 minutes with no accessories on.
Turn off engine for two minutes
Start engine again and run for 2 minutes with every accessory turned on.
Turn engine off again.

This process has always worked for me when re-setting the idle

BTW,why so big of injectors?

84LX89GT · 04-21-2003, 12:53 AM

I went with 30's because i'm going to run a 150 hp shot of nitrous, i really don't want to lean out, plus i'm going to be installing heads, cam and porting basically everything i can wield a grinder to. I also have a distant plan of a stroker or some other wild combination that won't be streetable anyway. I figured i could make the 30's work for now until i actually need them (with a 150 shot, i'm hoping they'll come in handy

)

84LX89GT · 04-21-2003, 10:10 PM

i tried setting the idle, with the iac disconnected, but it doesn't want to idle, it surges about 500-750 rpm up and down and dies after about 3 surges. It even does this with the IAC. I'm tempted to set the idle at 1500 for now just to get it to work, but that probably won't even work, the car just doesn't like what i've done to it

Coupe50h · 04-21-2003, 10:46 PM

im having a similair problem, i mean my car will not idle when cold? it started after my heads/cam install, the car idles like new when warm though, it will just surge like crazy on cold startup, and i tried cleaning iab, tuning up, plug's, cap, rotor, setting tps voltage, reseting ecu, nothing, it's getting frustrating.

84LX89GT · 04-23-2003, 04:04 PM

I found out my car's fuel pressure, running is up in the 100+ psi range so something is restricting it. The regulator is adjustable with the car off, so i think either the return lines are too small or something is plugged somewhere. I checked and nothing is pinched.....there's always more work that has to be done

04-20-2003, 10:44 PM	#1
84LX89GT Mustangs Join Date: Jul 2000 Posts: 1,938	30lb/hr injectors in.....too rich at idle, help! Ok, i installed some 30lb/hr injectors, Ford Racing 70mm MAF (for injectors) and a walbro 255lph pump the other day (in preperation for running nitrous). Anyway, now the thing runs too rich at idle (floods engine), at all other speeds it runs fine. I reset the fuel pressure to 35psi key on from 42 psi and it seems to run a bit better at times, but it still doesn't like to idle. My question is, what should i tinker with to get this thing to idle? Should i reset the throttle blade more open and lower TP voltage (but make sure it shows WOT at full throttle)? Would an idle adjuster work? I know 30 lb injectors and 255lph fuel pump is way overkill for regular driving, but i just want to be able to drive from the track and back without it dying at stoplights. All ideas are greatly appreciated. __________________ 2005 Suzuki Hayabusa GSX1300-R 1980 Ford Thunderbird - 255 V8 ported heads, 5.0L ported stock headers, O.R. H-pipe and Flowmaster 2-chambers, dual roller timing chain hi-po Mack Truck hood emblem 1985 Mustang GT 5.0L T5, F-303, GT40p, headers, off-road h, flowmasters, MSD stuff, etc. Sold 02/06/04 1989 Mustang GT ET: 13.304@102.29 mph (5-24-03) Sold - 1998 Mustang Cobra coupe, 1/4 mile - street tires: 13.843@103.41 (bone stock) Last edited by 84LX89GT; 04-20-2003 at 11:37 PM..

04-20-2003, 10:47 PM	#2
84LX89GT Mustangs Join Date: Jul 2000 Posts: 1,938	Oh, and just so it's in the clear, i double checked that all vacuum lines are connected and sprayed brake clean around all gaskets and vacuum lines and my vacuum gauge shows the same vacuum (19in) that it had before the install. __________________ 2005 Suzuki Hayabusa GSX1300-R 1980 Ford Thunderbird - 255 V8 ported heads, 5.0L ported stock headers, O.R. H-pipe and Flowmaster 2-chambers, dual roller timing chain hi-po Mack Truck hood emblem 1985 Mustang GT 5.0L T5, F-303, GT40p, headers, off-road h, flowmasters, MSD stuff, etc. Sold 02/06/04 1989 Mustang GT ET: 13.304@102.29 mph (5-24-03) Sold - 1998 Mustang Cobra coupe, 1/4 mile - street tires: 13.843@103.41 (bone stock)

04-21-2003, 12:53 AM	#4
84LX89GT Mustangs Join Date: Jul 2000 Posts: 1,938	I went with 30's because i'm going to run a 150 hp shot of nitrous, i really don't want to lean out, plus i'm going to be installing heads, cam and porting basically everything i can wield a grinder to. I also have a distant plan of a stroker or some other wild combination that won't be streetable anyway. I figured i could make the 30's work for now until i actually need them (with a 150 shot, i'm hoping they'll come in handy ) __________________ 2005 Suzuki Hayabusa GSX1300-R 1980 Ford Thunderbird - 255 V8 ported heads, 5.0L ported stock headers, O.R. H-pipe and Flowmaster 2-chambers, dual roller timing chain hi-po Mack Truck hood emblem 1985 Mustang GT 5.0L T5, F-303, GT40p, headers, off-road h, flowmasters, MSD stuff, etc. Sold 02/06/04 1989 Mustang GT ET: 13.304@102.29 mph (5-24-03) Sold - 1998 Mustang Cobra coupe, 1/4 mile - street tires: 13.843@103.41 (bone stock)

04-21-2003, 10:10 PM	#5
84LX89GT Mustangs Join Date: Jul 2000 Posts: 1,938	i tried setting the idle, with the iac disconnected, but it doesn't want to idle, it surges about 500-750 rpm up and down and dies after about 3 surges. It even does this with the IAC. I'm tempted to set the idle at 1500 for now just to get it to work, but that probably won't even work, the car just doesn't like what i've done to it __________________ 2005 Suzuki Hayabusa GSX1300-R 1980 Ford Thunderbird - 255 V8 ported heads, 5.0L ported stock headers, O.R. H-pipe and Flowmaster 2-chambers, dual roller timing chain hi-po Mack Truck hood emblem 1985 Mustang GT 5.0L T5, F-303, GT40p, headers, off-road h, flowmasters, MSD stuff, etc. Sold 02/06/04 1989 Mustang GT ET: 13.304@102.29 mph (5-24-03) Sold - 1998 Mustang Cobra coupe, 1/4 mile - street tires: 13.843@103.41 (bone stock)

04-21-2003, 10:46 PM	#6
Coupe50h Registered Member Join Date: Aug 2002 Location: SanAntonio, Tx Posts: 957	im having a similair problem, i mean my car will not idle when cold? it started after my heads/cam install, the car idles like new when warm though, it will just surge like crazy on cold startup, and i tried cleaning iab, tuning up, plug's, cap, rotor, setting tps voltage, reseting ecu, nothing, it's getting frustrating. __________________ X-Texas highway patrol ssp 1990 coupe - exploder Gt-40 iron heads, Explorer intake, 19 lber's. E-cam. crane 1.7 rollers. 190fp. 75mm maf. 65mm tb, tubular subframe connectors, mac cai, Asp crank pulley, T-5, king cobra clutch, flowtech 1-5/8 unequals, mac X-pipe Frpp driveshaft, lakewood Lca's. race weight 3,160 12.69 @ 107.35, 1.71 60' 26x8.5 drag's 3.90 gear 13.20 @ 106.91 - 235/60/15 firestones 2.3 60' 3.27 gear

04-20-2003, 11:56 PM	#3
Mustanguy Guest Posts: n/a	Clear the computers memory by disconnecting the battery for about 20 minutes. Disconnect the Idle air bypass solonoid Reconnect battery Start engine and set idle speed to desired RPM with stop screw on your throttle body Turn off engine and reconnect the air bypass solenoid set TPS to 0.90 - 0.95 volts (Don't go over 1.0 volts Use a digital volt meter when yoiu set this Start engine and let it idle for 2 minutes with no accessories on. Turn off engine for two minutes Start engine again and run for 2 minutes with every accessory turned on. Turn engine off again. This process has always worked for me when re-setting the idle BTW,why so big of injectors?

04-23-2003, 04:04 PM	#7
84LX89GT Mustangs Join Date: Jul 2000 Posts: 1,938	I found out my car's fuel pressure, running is up in the 100+ psi range so something is restricting it. The regulator is adjustable with the car off, so i think either the return lines are too small or something is plugged somewhere. I checked and nothing is pinched.....there's always more work that has to be done __________________ 2005 Suzuki Hayabusa GSX1300-R 1980 Ford Thunderbird - 255 V8 ported heads, 5.0L ported stock headers, O.R. H-pipe and Flowmaster 2-chambers, dual roller timing chain hi-po Mack Truck hood emblem 1985 Mustang GT 5.0L T5, F-303, GT40p, headers, off-road h, flowmasters, MSD stuff, etc. Sold 02/06/04 1989 Mustang GT ET: 13.304@102.29 mph (5-24-03) Sold - 1998 Mustang Cobra coupe, 1/4 mile - street tires: 13.843@103.41 (bone stock)

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