ls3fox

hi i have a ls3 swapped foxbody with holley dominator plug and play setup on it and while cranking i sometimes lose rpm, fuel pressure and spark. we check over the wiring all the grounds are connected and all the plugs are in. we havent been able to get the car to start at all yet because we had a few other issues got them all sorted out except the rpm issue . it shows stall most of the time and then all of a sudden it has rpm and fuel pressure. any help would be greatly appreciated thanks

LSX Power Tuning

iTrader: (4)

Make sure you wired your power, ground and ignition wires exactly like holley recommends. I know that sounds very basic but thats the problem 99% of the time when someone brings us a holley car to tune. If all that is correct make sure you setup the ecu for your ignition, 58x, COP, or whatever your running.

gametech

iTrader: (1)

Also put a voltmeter on the main power to your ecu while cranking. Your battery or wiring may be allowing too much voltage drop while cranking.

Project GatTagO

iTrader: (7)

Where is the white/red wire connected? Sounds to me like it is connected somewhere that does not have power while the ignition switch is in START. So the ECU basically shuts off while you are cranking and turns on when you turn the key back to RUN.

Andrew

Eldogg

Are you using the Factory Cam position extension harness? If so remove it.

gametech

iTrader: (1)

Damn, I forgot about this, but I used to work at a place with a forklift wired that way. It would never start until you backed off of the switch, which then re-enabled the ignition.

ls3fox

ok so too update this we got the car up and running but im still having ptoblems with the holley if we try to ground it too anything in the car or to the main battery like holley suggests it will only start some of the time and other times it'll just kick the fans on and the car wont start so for the hell of it we stuck a second battery in the car and put the ground to that and the car starts every time but even with that every once in a while itll start but only run on 4 cylinders so im kinda lost with this thing at thus point

Project GatTagO

iTrader: (7)

User error.

ls3fox

its definitely possible but so far no body can tell me what im doing wrong im more then willing to try any suggestions

LSX Power Tuning

iTrader: (4)

It sounds like you have a wiring issue to me, then possibly a configuration issue.

ls3fox

the wiring issue i agree on but me and a buddy have been over every thibg at least 4 times now we talked to holley tech support we were on a first name basis lol cant figure it out

and i dont know about a vonfiguration issue cause when it runs right it really runs right, makes good power

Project GatTagO

iTrader: (7)

Did you check what I wrote in post #4?

Andrew

ls3fox

yes the red and white wire has 11.1 volts during cranking the car runs now just has quirky problems and i have to use a second battery to help make it more consistent took it to the track yesterday and it wouldnt data log one pass and the next pass it data logged the pass but it skipped half of first gear and during the run my holley dash didnt keep up either and i tagged the rev limiter i searched it and gound people were having problems with the data log if they had alot of rfi so im gonna look in too that next but if you have any other suggestions im open to them

Old Geezer

iTrader: (3)

"Dirty grounds/wiring getting rfi.....

ls3fox

i was doing alot of reading about rfi so i moved my o2 sensor wiring i had non resister spark plugs i changed them and i added a couple of grounds ill still have to try it out to see if it helped but im hoping lol

LilJayV10

iTrader: (39)

That will dump all sorts of RFI noise into the system, especially that particular harness because it's low voltage.

LSX Power Tuning

iTrader: (4)

We run non-resistor plugs on a lot of cars we race, it’s not the plugs. Grounds are VERY important with Holley, we ground the block in 2 places and run a 10gauhe wire to battery.

ls3fox

i added 2 more grounds to the block i still have to run one ti the battery in the back