Conversions & Swaps LSX Engines in Non-LSX Vehicles
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need help please😩

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Old Dec 17, 2018 | 11:04 AM
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Hello everyone,Im new to ls efi game , I need some help . I just got done with my turbo build . This is what done to it . 2002 lq4 stock bottom end ljm sport stage 2 cam, upgraded the push rods , trunnions , has 317 aluminum-heads ,80 lb injectors, stock truck return style intake with 3 bar map , aeromotive buypass fuel regulator thats reading 60lb stock computer thats been tuned to run with 3 bar map . With Holley dominator 1200hp fuel pump ,I cant get it to idle with the fuel pump on , but when I let the fuel rails fill up and turn the pump off and hold the gas peddle to the floor it will run good until it runs out off gas . Any suggestions will help. Thanks
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Old Dec 17, 2018 | 02:13 PM
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sound like you need to take some fuel out at idle
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Old Dec 17, 2018 | 02:25 PM
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Its dumping fuel at idle like doug said.
Holding the pedal to the floor activated flood clear, which shuts the injectors off. If it starts with the pedal down, its because its starting on the excess fuel that has already been poured in.
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Old Dec 17, 2018 | 05:08 PM
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Is this something I would ner a computer and hp tuners to do that ? That is why I sent the computer out to have tune flashed on it.
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Old Dec 17, 2018 | 05:18 PM
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Mail order tune for a turbo setup is pretty much going to be an instant failure. You're more likely to try describing a paint color over the phone and having them send you an exact match.
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Old Dec 17, 2018 | 06:43 PM
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Whats your fuel pressure set at? What 3 bar mapr sensor do have? Was the map sensor part number given to the tuner? We do alot of mail order tunes for boost but only as startup tunes and even then its impossible to get all of them right in one try. We turn down alot of them due to parts combo nations that we know we couldnt get right in as single try.
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Old Dec 17, 2018 | 08:18 PM
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Fuel pressure is at 60psi , the 3 bar map is a standard brand , the tuner said he tuned it for 3 bar map and 80lb injectors. Wonder if I should turn the fuel pressure down ?
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Old Dec 18, 2018 | 08:19 AM
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There are different linear and offset scaling for different map sensors, not all of them are the same. You need to plug into the vehicle and check what the map reads with the key on and engine off. I also would recommend to ask the tuner what base pressure the tune was set for. If it was set for 45 psi and your at 60 thats a big difference. Lowering the fuel pressure would lean it. out.
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Old Dec 18, 2018 | 08:45 AM
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if it's just dumping fuel into the motor and is so fat it wont even run ....stop....just had a fella tear up his motor doing that when a bad cam sensor signal (due to a mechanical failure) just poured gas into his motor

it's fairly easy to get a decent base tune to fire a turbo car on and begin to drive it around for street tuning on as long as you have good injector data
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Old Dec 18, 2018 | 09:07 AM
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What was your fuel pressure at idle?
Since you're new to EFI, did you measure the base pressure with the vacuum line hooked to the regulator?
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Old Dec 18, 2018 | 01:54 PM
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hey guys thanks for the responses. I’m going to call the tuner to ask these questions and try to hook the vacuum up from the regulator to some vaccum and try this out .
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Old Dec 18, 2018 | 02:02 PM
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Originally Posted by Bossassnova
hey guys thanks for the responses. Im going to call the tuner to ask these questions and try to hook the vacuum up from the regulator to some vaccum and try this out .
If you haven't hooked the vacuum line to the regulator yet, do it first.
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Old Dec 18, 2018 | 04:46 PM
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Might be a dumb question but I have to ask ? If I hook the vacuum line to the aero motive fuel regulator will the fuel pressure drop or is it giving me a false psi reading with out the vacuum being Applied to it?
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Old Dec 18, 2018 | 06:04 PM
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It should stay the same, rising ONLY under manifold pressure
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Old Dec 18, 2018 | 06:22 PM
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Originally Posted by Bossassnova
Might be a dumb question but I have to ask ? If I hook the vacuum line to the aero motive fuel regulator will the fuel pressure drop or is it giving me a false psi reading with out the vacuum being Applied to it?
assuming you have a boost referenced regulator it should reduce fuel pressure when seeing a vacuum signal and increase fuel pressure when seeing a boost signal at a ratio of 1:1 manifold pressure:fuel psi. If your manifold signal line was not connected, it would be safe to say your fuel pressure was too high at idle, assuming the fueling and injector parameters are set correctly in the tune.
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Old Dec 18, 2018 | 06:57 PM
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Okay , yes I have a boost reference fuel regulator and I didn’t have the vacuum line hooked up to to it so I will give that a try ..��thanks
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Old Dec 18, 2018 | 06:57 PM
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I meant to add that it doesnt sound like the manifold signal line being disconnected alone is the issue. It should help when you connect it, but I suspect the tune is going to need some help.

Also, make sure to change the oil out right away. Running it this rich will dilute the oil with gas and can kill bearings quick
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Old Dec 18, 2018 | 10:37 PM
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Originally Posted by G Atsma
It should stay the same, rising ONLY under manifold pressure
I don't know that particular regulator, but every boost referenced regulator I've ever owned drops fuel pressure from the base at vacuum and raises it with boost. Is this one different?
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Old Jan 8, 2019 | 03:52 PM
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I contacted Bossassnova via PM and learned he lives 50 miles south of me but works in Portland.
He brought me the ecu which I read and it is indeed a 3bar tune.
MAP sensor scaling is correct for the brick style sensor he is using.
The tune is NOT set up for a return style FPR. Which isn't a huge deal.
The tune is also scaled 50%.
It is a base tune, nothing more.
I have a solid 6.0 3 bar tune using the SD80 that I can try if this tune isn't going to run.

Anyway, next step is for me to go have a look at the car, plug in with hpt and see what is really going on.

Ron
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Old Jan 8, 2019 | 09:18 PM
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Damn youre one helluva good guy for stepping in to help! I wish you lived closer to me.

Cheers!
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