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Discussion Starter #1
So I got a new problem fellas . Backround 90 mustang with vortech v2 . 60lbs injectors 1.7 skorpion rockers. B303 cam . Aero 340 fuel pump. Sct 90mm maf . And sct chip . Advanced timing 10 degrees . Problem im having is car fires right up runs really rough. Smells really rich . I tap the throttle bogs down and then rpm fly up . I have fuel pressure at 32 psi per my tuner . And timing per tuner . And idea what is going on ?
 

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misfire causing NO FUEL to burn.......02s see the lean condition and the ECM adds fuel just like its designed to do
 

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find the holes that are misfiring, find the cause, spark fuel compression and repair

why does it smell like fuel?

fuel goes in the engine, then leaves the tailpipe........why should it change in smell when it is not being combusted?
 

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Discussion Starter #5
find the holes that are misfiring, find the cause, spark fuel compression and repair

why does it smell like fuel?

fuel goes in the engine, then leaves the tailpipe........why should it change in smell when it is not being combusted?
Sorry I read your message wrong .
 

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Did this ever run correct for you? Mail order time? Tuner feels lowering your fuel pressure will forward x you issue? Dongle to switch to other programs? I had a switch go bad and wouldn't read tune, removed and read 1st time fine.
 

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Don't you have a wideband O2 sensor??? Any boosted car should have one. I can't imagine running without one.

When you first start the car, it should be running in open loop until the O2 sensors heat up and begin to trim the fuel.

Turning the fuel pressure down isn't the way to fix a rich issue at idle, especially on a boosted car.

Is it a blow through or draw thru setup? Is this problem new or only happened after tuned? Once the car has been running for a few minutes, does it lean out.

Assuming it really is running super rich and not from misfires (without having a wideband O2 sensor) there could be many things wrong (assuming it is in open loop).

1 - Transfer function is incorrect on the tune.
2 - Injectors setting are wrong in the tune.
3 - MAF is damaged or the ECU is not getting voltage, I would log the output voltage with a multi-meter (it should be around 0.5-1 volt at idle, not 0 or 5.
4. What kind of 4 pin to 6 pin adapter are you using on the MAF? The old adapters have known to make poor contact (checking output voltage would help).
5. Depending on how the MAF is plumbed in, it could be vacuum leak.
6. Are these good injectors (and not some Chinabay injector for $12 a piece)?
 

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Discussion Starter #12
Don't you have a wideband O2 sensor??? Any boosted car should have one. I can't imagine running without one.

When you first start the car, it should be running in open loop until the O2 sensors heat up and begin to trim the fuel.

Turning the fuel pressure down isn't the way to fix a rich issue at idle, especially on a boosted car.

Is it a blow through or draw thru setup? Is this problem new or only happened after tuned? Once the car has been running for a few minutes, does it lean out.

Assuming it really is running super rich and not from misfires (without having a wideband O2 sensor) there could be many things wrong (assuming it is in open loop).

1 - Transfer function is incorrect on the tune.
2 - Injectors setting are wrong in the tune.
3 - MAF is damaged or the ECU is not getting voltage, I would log the output voltage with a multi-meter (it should be around 0.5-1 volt at idle, not 0 or 5.
4. What kind of 4 pin to 6 pin adapter are you using on the MAF? The old adapters have known to make poor contact (checking output voltage would help).
5. Depending on how the MAF is plumbed in, it could be vacuum leak.
6. Are these good injectors (and not some Chinabay injector for $12 a piece)?
Thanks for the info its a motor rebuild . Never ran before this . I have not got the wideband in yet waiting to have a bond welded in . I guess that'll be my next step once I check misfire .
 

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Could check for codes while you're investigating, pull plugs and see which ones are fouled, then determine why.
 
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