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Is the firing order and the ignition timing correct? Do you have spark to the #1 plug when the #1 piston is at approx. TDC on the compression stroke? Do you have a nice, smooth spray pattern? If the engine is flooding, are the injectors dribbling fuel when the engine is not rotating? What happens when you hold the throttle open while you're cranking the starter?
Everything is as u say. No dripping of fuel and good spray when cranking. Need more air to fuel. Tried throttle open and same. It wants to go but then fades out. Good burst at first then just turning
How did you determine it "Needs more air to fuel"? Do you have a scanner attached? What is your A/F ratio?
If it "fades out", you may actually have too little fuel. What happens when you spray Starting Fluid into the intake while you're cranking the engine?
Check your fuel pressure by removing your fuel filter, then putting a "T" in a fuel hose to replace the filter. Check pressure at the "T". Do you have a clean fuel filter?
Tried more gas don't like starter fluid in new engine and have 85 vette fuel pump. New filter . Lines are cleaned and tank also. Will check each plug wire . Reason for more air injectors are pumping and butterflies shut. Like choke on carb. I thought ecm which is new would take care of choke
2 things. Is the map sensor working and hooked up to the correct vacuum port? I had a similar problem on mine and that was the cause. Absolutely **** rich. Also, does it enter clear flood mode when you hold the pedal wide open and crank. Ie does injector pulsing stop? If that doesn't check out something else may be going on.
My bet is on too much fuel pressure or incorrect timing.
If a standard engine has more than 15psi they behave like that. This could be the case if you have installed a higher flow pump (which you have). Do you know how to adjust the fuel pressure regulator on the left hand throttle body?
With the timing you can simply set it by eye i.e. turnover the engine until it is just before TDC and rotate the distributor unit the rotor is coming up to number one spark plug lead, and you will be close enough to get it to run. Should probably disconnect the EST connector and set the timing with a light as soon as it starts.
But you said a couple of other things as well. You said that you replaced the ECM why? And with what? If it was replaced with a standard one then there is less scope for problems, best to get the engine going and then change the ECM when you have a known good baseline.
Also you said that you built the engine top to bottom so I guess you need to burn a cam in (unless it’s a roller). If that’s the case you shouldn’t let it idle. It should be cycled between 1500 and 3000 for 20 min.
Anyway hope that’s helpful
Thank you vacuum is shown on left side of back injector. 85 pump is only 15 lbs however I am putting in gage to check I believe I have tdc and is btdc now. Found 1 bad plug wire and mini starter not disengaging. Cam not roller just better I hope. Thank you again. 🙄
Thank you vacuum is shown on left side of back injector. 85 pump is only 15 lbs however I am putting in gage to check I believe I have tdc and is btdc now. Found 1 bad plug wire and mini starter not disengaging. Cam not roller just better I hope. Thank you again. 🙄
Not sure what you mean about vacuum and the 85 pump has a higher flow rate which in theory shouldn’t matter with regard to pressure but sometimes pressure does need to be adjusted when a higher flow pump is installed.
Anyway sounds like you are on the right track. Check fuel pressure it will come up as soon as you turn the key on and then drop off if you don’t start the car (this is normal).
When you are burning the cam in everything will get hot (real hot). I had two high volume fans blowing on my engine and the headers were glowing bright red. It’s better if your timing has a bit of advance but it’s important not to let the engine idle so that’s a bit hard. I did mine in three 10min runs and I melted a plug lead that wasn’t pushed in far enough. Anyway I’m sure you would have got some information with the cam. Also don’t forget to use the zinc additive that the cam manufacturer recommends for the burn in and first 100 miles or so.
Also maybe go back to your original ECM to rule that out.
