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I see there are quite a few people on here with the same issue. Mine will idle fine start fine and until about 1/2 throttle is fine. As soon as you give anything past that it starts cutting out and what seems to me like choking or starving for fuel. I’ve shimmed the valves, new timing chain(timing marks are spot on), new water temp sensor, k&n air filter, does have HMF optimizer that I set back to specs on website when this started happening. I’ve read on other threads about the fuel pump so I ordered one of those. That’s my next step if that doesn’t work what should I do next?
 

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I see there are quite a few people on here with the same issue. Mine will idle fine start fine and until about 1/2 throttle is fine. As soon as you give anything past that it starts cutting out and what seems to me like choking or starving for fuel. I’ve shimmed the valves, new timing chain(timing marks are spot on), new water temp sensor, k&n air filter, does have HMF optimizer that I set back to specs on website when this started happening. I’ve read on other threads about the fuel pump so I ordered one of those. That’s my next step if that doesn’t work what should I do next?
Welcome to the Forum

Check your fuel pump strainer for being dirty/clogged...How to clean your fuel pump How to clean fuel pump
 

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Discussion Starter #3
I tested the fuel pump it’s working fine. I feel like I’ve tried everything. How can you set a HMF fuel optimizer to give more fuel at high rpms? Also noticed the fan not turning on relay was buzzing. I bought a new one of those it doesn’t buzz anymore. How can I check if the engine is getting coolant also?
 

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I tested the fuel pump it’s working fine. I feel like I’ve tried everything. How can you set a HMF fuel optimizer to give more fuel at high rpms? Also noticed the fan not turning on relay was buzzing. I bought a new one of those it doesn’t buzz anymore. How can I check if the engine is getting coolant also?
You tested the fuel pump...What's the pump fuel pressure...?...43psi standard

Need to know more about your air intake before setting your fuel controller...!
Is your intake tube stock or upgraded...?..Stock is circled in picture below...

To check if your coolant is circulating...remove the radiator cap & look in to see the coolant level & if it's moving with the motor running & squeeze the lower hose a few times to burp any air out...!!!
 

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Discussion Starter #6
The intake tube is stock. I just took the fuel pump out and tested it in gas with a 12v battery hooked to it and it shot gas out how do I test pressure?
 

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The one time I took it out it was very hot out and I shit it off and I heard the coolant boiling
 

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The one time I took it out it was very hot out and I shit it off and I heard the coolant boiling
Make sure your fan comes on...Check the 10amp fuse & relay... if the coolant is over 220 ℉ the water temp sensor will force the DFI into safe mode & can cause the symptoms your having...
So open the radiator & check the level with the motor running...


The intake tube is stock. I just took the fuel pump out and tested it in gas with a 12v battery hooked to it and it shot gas out how do I test pressure?
To test the fuel pressure you need an fuel injector tester like this... High Quality Fuel Injection Gauge Pressure Tester Test Car System Pump Tool Kit | eBay
 
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