New engin doesnt run
Thread Starter
Intermediate
Joined: Oct 2017
Posts: 27
Likes: 0
New engin doesnt run
Hi
im having problems. With my 1969 c3.
the car has a new blueprint 454 engine whi ch has not been driven more than maybe 1600 or 1700 miles
it has a new efi installed,new alternator , new start motor , msd ignition fuelpump and so on
now the problem
it doesnt run!!!
but seriously it has never ran smoothly as long as i own it . The number of cylinders running never toped the magic eight. Hence i aquiered the new engin
the last incident the car rann very rich. Despite efi(it has never been fully educated!!) but yet semi smooth. Efter about 15 miles i turned off the engine for a minute. When i tryed to restart it it was. Very hard to get the engine running and when. It ran the rpm went down from 600 to 200 rpm and then stalled.i managed to drive it to a better spce to park it But i had to. Rush the motor . I turn it off and then it did not restart and i almost emptied the. Battri and during. Start attempts It spited out blck smoke from both ends,the exhaust and the efi
after about 3 hours i manage to restart it but i chose to tow it back to the shop and there it couldnt be started up
now im looking forwrd your inputs if the problem is mechanically or electrically
thanks. For your inputs
im having problems. With my 1969 c3.
the car has a new blueprint 454 engine whi ch has not been driven more than maybe 1600 or 1700 miles
it has a new efi installed,new alternator , new start motor , msd ignition fuelpump and so on
now the problem
it doesnt run!!!
but seriously it has never ran smoothly as long as i own it . The number of cylinders running never toped the magic eight. Hence i aquiered the new engin
the last incident the car rann very rich. Despite efi(it has never been fully educated!!) but yet semi smooth. Efter about 15 miles i turned off the engine for a minute. When i tryed to restart it it was. Very hard to get the engine running and when. It ran the rpm went down from 600 to 200 rpm and then stalled.i managed to drive it to a better spce to park it But i had to. Rush the motor . I turn it off and then it did not restart and i almost emptied the. Battri and during. Start attempts It spited out blck smoke from both ends,the exhaust and the efi
after about 3 hours i manage to restart it but i chose to tow it back to the shop and there it couldnt be started up
now im looking forwrd your inputs if the problem is mechanically or electrically
thanks. For your inputs
Team Owner
Joined: Oct 2004
Posts: 81,241
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From: altered state
St. Jude Donor '05
Could be so many things not sure we can diagnose it. First thing Id be checking is the fuel pressure
Location? Bet theres a member nearby or a shop that could be recommended
One thing about EFI (aftermarket), simply dont trust them to have OEM reliability
Is this a self tuning system or does it need to be truly tuned? Somethings way outta wack
12 volts to all critical components? (no ballast resistor)
Location? Bet theres a member nearby or a shop that could be recommended
One thing about EFI (aftermarket), simply dont trust them to have OEM reliability
Is this a self tuning system or does it need to be truly tuned? Somethings way outta wack
12 volts to all critical components? (no ballast resistor)
Race Director
Joined: Jul 2015
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From: SW Florida.
make sure the efi has power all the time on the terminal it needs power alla time on.. otherwise it has to re-learn from scratch every time you take the key out. THEN find a base program which is closer to what the car needs to run. what fuel pressure do you have and what fuel pressure are you supposed to have. does efi run the timing curve? and if so, you need to have the correct base timing as there is no TDC sensor in the timing cover like a gen 6. CEL codes? and WHAT efi?
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,209
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
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which EFI is it and what intake does it have on it?
It souds like you are running very rich and it is probably the intakes fault. It could be the initial parameters of the EFI are incorrect and it not set up to run on a v8 or something as simple as that for that matter or the timing itself wasnt set up to match the sytem options that are selected. THere is a lot that goes into setting up the EFI systems to work with what you are using.
My best guess from your description is that you are flooding it with by having an incompatible intake or setting. It could also be the timing as well. I ran a old torquer 2 on my 327 and it ran great. I put that same EFi on my big block with a factory aluminum dual plane and it left puddles in the the intake and in the valve passages. I dumped the EFI and put on a tripower and it ran great.
It souds like you are running very rich and it is probably the intakes fault. It could be the initial parameters of the EFI are incorrect and it not set up to run on a v8 or something as simple as that for that matter or the timing itself wasnt set up to match the sytem options that are selected. THere is a lot that goes into setting up the EFI systems to work with what you are using.
My best guess from your description is that you are flooding it with by having an incompatible intake or setting. It could also be the timing as well. I ran a old torquer 2 on my 327 and it ran great. I put that same EFi on my big block with a factory aluminum dual plane and it left puddles in the the intake and in the valve passages. I dumped the EFI and put on a tripower and it ran great.
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,209
Likes: 9,347
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
And does it have a new coil?
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Race Director
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Cruise-In VIII Veteran
Running so rich it's fouling plugs is my quess. Bad O2 sensor? ran poorly before new engine as well? issues with the way everything is wired?
Le Mans Master
Joined: May 2007
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From: North tonawanda NY
Le Mans Master
Joined: Apr 2001
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From: Was New Orleans but swam to Baton Rouge LA
Cruise-In IX Veteran
So many questions. What distributor are you running? What is the timing set at? There could be a slew of issues as to why it won't run. I would start with looking into the distributor, coil, and power feed to them. If that is all good and you can get it running, then look at the timing. After that is when I would try to look at the EFI setup.
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,209
Likes: 9,347
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
YOur other thread says that you went back to the carburetor. Who makes the carburetor, Holley, Edelbrock, or Quadrajet. As for the probelm Tak the cap off the distributor and look for rust or water. The cap could have a small crack in it that you can not see until it gets hot. If so that will cause all of the ignition problems. A bad coil will as well. How is the distributor wired. If it is using the stock wires they may not be giving your HEI enough power and you need to get a different power source, THe yellow wire from the wiper motor is a good source. IF your wiring from the starter is in correct your starter may not be shutting off and that is why it is hot and you burned up the other one. When people wire in a new HEI they sometimes dont wire it correctly and this becomes an issue
1967 Pedal Car Champion
Joined: Mar 2020
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From: US-PNW
Sounds like multiple issues could be going on. You need to straighten out your spark first. What distributor do you have? points/condenser? HEI? stock GM? aftermarket?
If by stifts you are referring to spark plugs, black indicates much too rich or oil-fouled. Is the black coating dry or wet looking?
Post a pic of your carb and distributor without shielding or the air cleaner.
If by stifts you are referring to spark plugs, black indicates much too rich or oil-fouled. Is the black coating dry or wet looking?
Post a pic of your carb and distributor without shielding or the air cleaner.