holden 6 , 400hp fitech , idle speed starts high then drops
have the 400hp fitech fitted to a (australian) holden 6.
got it running, but at every start , wether hot or cold it goes to 2000 rpm then drops down to idle, is there any way to stop this , tried the loop adjustment but didnt make any differance.,
anyone help?
attached is a datalog file at idle...
had to convert csv to pdf.
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I am no expert, I think you go to Go EFI Tuning - crank and warm up - crank IAC Mult - adjust the IAC [Idle Air Control] down, while since I did mine, I think I set it to 70. They set it up for a 350 cube or so to wet the manifold, too much for smaller cubes. Same section has all the crank fuel and after start settings.
Quote from turbo1600 on September 13, 2021, 7:04 pmhave the 400hp fitech fitted to a (australian) holden 6.
got it running, but at every start , wether hot or cold it goes to 2000 rpm then drops down to idle, is there any way to stop this , tried the loop adjustment but didnt make any differance.,
anyone help?
attached is a datalog file at idle...
had to convert csv to pdf.
Dont convert the file and leave it as is, as it is missing info in the data log such as error codes. Upload a unconverted file. Did you do the IAC adjustment which should read between 3-10 at idle @ 170 degrees F and the TPS should remain at 0 when adjusting the screws. Also look for vacuum leaks . What I do notice is low voltage from the alternator. You should be around 13.9 to 14.5v. Because of Fuel Injection you need a higher output alternator with a min of 100 amps and have a heavy gauge charge wire from the alternator to the battery. You will need a more powerful alternator if you are running electric fans.The gauge of wire will vary depending on length. On a 100 amp alternator, I recommend a min 8 gauge or a 6 Gauge wire. Also is the fuel pump intank or inline?
post wont allow me to load .csv says only : jpg,jpeg,gif,png,bmp,pdf files
fitech said that 12.8v wont cause any problems.. i did a IDLE CONTROL data log. cam is on selection 2. tps is zero
iac adjustment reads around 7 to 8.
idle control log : https://easyupload.io/v8ceic
As I suggested, lower your Crank IAC. Unbalanced butterflies can also cause a problem, seems to be okay from IAC and TPS. SodaPop knows his stuff, he can go in depth for the difficult stuff. I only know the basics that I learnt from battling on my own [Aussie], got mine running like a new car after a lot of reading and trial and error. Mostly the low voltage problem is on cranking, some say 11.5v minimum, others 12v, will never run correctly if too low, so need a decent battery. I found a 80 amp alternator more than adequate. Vacuum leak shows up as running super rich at idle, will wreck the O2 sensor. Leak in exhaust shows as a rich spike when you back off while cruising. He doesn't like in line pumps, I have a inline Bosch 044 rubber insulated to the mount that is rubber bobbin mounted to the chassis, barely any noise, must be below the tank and two filters. Chinese copy failed, genuine good. Get it running reasonable then send in a datalog so that SodaPop can analyse it. Save your settings as you go along, if you are too far out you may have reset. Different cam settings are to do with vacuum, it alters the amount of fuel supplied.
Check that your secondary butterflies are returning back to "close" when you let the gas go. Try to push them close manually and see if this lowers your RPMs. Another way to test if that's the case is to do a quick tap of the gas pedal and see if the RPMs reduce. If so, you need to adjust the secondaries. I have posted the procedure elsewhere. If this is the case I can repost in this thread.
Everyone has their own experiences, I found when my secondaries were not fully closing, the revs were not dropping off by itself after the high revs on start up as is the case here, because it is a mechanical thing., only lowered when I pushed the linkage.