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Crate HEMI Engine Kit factory wiring problem

EvilBeast

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This install is for a 2014 392 in a '69 Charger. I have the 'Crate Hemi Engine Kit' - 77072454AB. The engine runs - once it starts. Multiple cranks, sometime several minutes.

I looked at the header - PDB1 (marked "PDBA on mine) going into the power distribution center. The 'FUEL PUMP FEED' (DB/Orange) is 18 Gauge, not 12G as in the Instruction Sheet (Rev 5.0). Also, that wire does not get 12V at Key-On, and the "FUEL PUMP RELAY CONTROL' wire next to it on same header does not get 12V at Key-On. I wired my fuel pump from another fused source to bypass this problem.

My problem is that it takes several minutes of cranking to fire the engine. Minutes - try, stop, retry, again. It should fire immediately. I have checked fuel line and there is plenty of fuel coming out of it if I disconnect it.

Are these problems related? Does the ECM have to see a load on the fuel pump circuit to send spark? Even if that were the case, why does the engine start after several minutes of cranking - it should never start.

Also, has anyone with this engine kit had a miswired or mislabeled PDB like mine? It's really concerning that the instructions are different from the actual wiring
 
Do you have a fuel pressure gauge? Sounds to me like its not building enough fuel pressure to work which is why it takes awhile for it to fire. I don't have any experience with the install kit you are using but I do with EFI systems in general and if the ecu isn't seeing enough fuel pressure it won't fire the ignition.
 
When I disconnected the fuel line from the in-tank pump, there was a steady stream with significant volume coming out with the pump on. But yes, I do have a FP gauge. Can you tell me where the fuel pressure gauge nipple is on the 392? Thanks!
 
I ran into a similar problem on my Viper, it wouldn't start right away, then would fire up but die right away. It would do this a few times and then finally run. I discovered that the ignition switch had an issue where it wasn't letting the FP run during starting. I discovered this by putting a FP gauge on it and watching it during cranking.

If you do have fuel pressure then its something in the ECU that is not allowing the engine to fire.
 
Cam sensor is another thing that will not let them start.
 
Are you far enough along to use a code reader in the OBD2 port?
 
Does the ECU have any type of diagnostic capability (ODBII port, laptop connection, etc)? You would think that a new crate engine should have good/working sensors but you never know. Newer EFI engines are pretty power sensitive meaning that if a sensor is not getting the proper voltage signal it will not work or talk to the ECU.
 
The ignition switch issue could be part of it. I mean, I wired the fuel pump to an accesory position in the fusebox aftermarket wiring harness (American Autowire B body kit) to get around the "FUEL PUMP RELAY CONTROL' line problem I mentioned earlier. If that accessory position loses voltage during cranking, that may be it. I can check that easily with a voltmeter. The fuel pressure check will be done too. Thanks, I'll be sure to report back in case someone looks up this thread in the future.
 
If using the factory ignition, IGN. 1 and IGN. 2 should be tied together.
 
I agree the factory Ignition switch does not provide power when cranking. What are you using for an Ignition switch.
 
There is no fuel pressure gauge bung, I ran the fuel lines from the tank to a connection on the driver side fuel rail - see photo. I checked the fuel flow and its excellent. The voltage for the pump in the tank goes to 12V then shuts off after about 3 secs. When cranking there is 0 volts. I checked this right at the Hemi Engine kit's FUEL PUMP FEED line. Is that wrong? You'd think there was enough fuel pressure in the rails to at least give a squirt or two so the engine could fire. And it does fire - only after many cranks and retries. Could the fuel injectors be clogged? Do you recommend a specific fuel injector cleaner or a procedure to clean them in the manifold?

IMG_1760.JPG
 
I agree you need to tie ignition 1 and 2 together, or use a relay so the pump is hot during crank. I did my holley setup with a relay because I am running stock ignition and a ballast. Use an automotive grade relay, like something stock from a newer vehicle. I had problems with the holley relay and aftermarket stuff, used junkyard relays are flawless.
 
There is no fuel pressure gauge bung, I ran the fuel lines from the tank to a connection on the driver side fuel rail - see photo. I checked the fuel flow and its excellent. The voltage for the pump in the tank goes to 12V then shuts off after about 3 secs. When cranking there is 0 volts. I checked this right at the Hemi Engine kit's FUEL PUMP FEED line. Is that wrong? You'd think there was enough fuel pressure in the rails to at least give a squirt or two so the engine could fire. And it does fire - only after many cranks and retries. Could the fuel injectors be clogged? Do you recommend a specific fuel injector cleaner or a procedure to clean them in the manifold?

View attachment 1111727
I doubt the injectors are clogged, I would bet you need to figure out how to get power to the pump during crank.
 
There is no fuel pressure gauge bung, I ran the fuel lines from the tank to a connection on the driver side fuel rail - see photo. I checked the fuel flow and its excellent. The voltage for the pump in the tank goes to 12V then shuts off after about 3 secs. When cranking there is 0 volts. I checked this right at the Hemi Engine kit's FUEL PUMP FEED line. Is that wrong? You'd think there was enough fuel pressure in the rails to at least give a squirt or two so the engine could fire. And it does fire - only after many cranks and retries. Could the fuel injectors be clogged? Do you recommend a specific fuel injector cleaner or a procedure to clean them in the manifold?

View attachment 1111727

On 3 seconds then off is how it should work, everytime you crank the pump will run 3 seconds, then off. Thinking a relay will fix this.
 
While I agree with your point that the pump SHOULD run while cranking, this is a factory manufactured harness and ECM kit. I'm concerned that doing an addon kind of thing to it will damage something. Has anyone here installed one of these kits and did you have to add on a relay? Please post a circuit diagram for your relay setup. Thanks!
 
So are you saying the wires marked fuel pump feed, and the fuel pump relay never have power with the ignition in run, or crank? Is it possible these 2 wires switch a ground? That could be used on the coil side of a relay, to power the pump.
 
Checked the plugs, dirty so cleaned them, reinstalled. Same problem. No start. I put some gas on the air filter, and it started - ran perfect.

Fuel pump feed has power on it for 3 secs after key-on, then dead, even while cranking, until engine is started. After engine start, full 12V. Stumped.
 
Does the wire marked fuel pump relay have 12 volts during cranking?
 
Question: does the ECM want to see some RPM before supplying voltage to the fuel pump during crank? I don't think there's a feed to the ECM from the tach circuit, maybe that's the problem?
 
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