New 383, start & idle issues, adj. idle stops & tps?
#1
TECH Regular
Thread Starter
New 383, start & idle issues, adj. idle stops & tps?
Just fired up my new Ellwein 383 yesterday and it is a bit hard to start unless you crack the throttle open a bit. I've read elsewhere that due to the increased displacement, the idle stops and TPS need to be adjusted to allow more air in.
Is this accurate? If so, any tips?
TIA
Is this accurate? If so, any tips?
TIA
#2
TECH Enthusiast
iTrader: (4)
You will need to adjust the throttle blade open to get the correct IAC counts at idle (I think they need to be around 60 or so but it has been over 15 years since I did this). You will also need to slot the holes of your TPS sensor and move it to continually show 0 % throttle at idle while adjusting your throttle blades (when you adjust the throttle blades you move the tps sensor position like you are pushing the gas pedal down).
#3
Village Troll
iTrader: (2)
Going through the same thing. I can't remember, but I believe there is a period of start cycles the PCM has to go through before it learns how to idle. Go ahead and open the blade stop screw a 1/4 or half a turn and then check voltage on TPS. Stupid question, but has it been tuned?
#4
Atlanta
As SSr says....you do have a tune for the new motor, right?
If so...
Your IAC counts are likely pegged, common on builds especially with larger TB's.
The open blade, slot TPS holes is one way of fixing.
You need a scan tool to read IAC counts and TPS VDC (or DVM meter).
IAC counts want to be 30-35 (32) with engine at operating temp. Adjust TB stop screw until they drop to 30-35 (they are likely pegged at 160 now). Then take the TPS off and slot the 3 screw holes (Golen has this procedure on their tech tip section of site) so you can "clock" (rotate) the TPS back so TPS VDC is around .67 VDC blades closed and 4.5 VDC blades full open
or
(do not do this without first scanning to see wtf IAC counts are.)
drill the hole between blades like where the stock one is on the 48. drill 1/8" hole, scan IAC. if still to high (likely) drill 1/64" larger, scan IAC again. Take baby steps as 1/64" larger makes a big difference
IMHO boring a stock TB to 52 is the way to go but you still need to enlarge the stock IAC hole
As SSr says....you do have a tune for the new motor, right?
If so...
Your IAC counts are likely pegged, common on builds especially with larger TB's.
The open blade, slot TPS holes is one way of fixing.
You need a scan tool to read IAC counts and TPS VDC (or DVM meter).
IAC counts want to be 30-35 (32) with engine at operating temp. Adjust TB stop screw until they drop to 30-35 (they are likely pegged at 160 now). Then take the TPS off and slot the 3 screw holes (Golen has this procedure on their tech tip section of site) so you can "clock" (rotate) the TPS back so TPS VDC is around .67 VDC blades closed and 4.5 VDC blades full open
or
(do not do this without first scanning to see wtf IAC counts are.)
drill the hole between blades like where the stock one is on the 48. drill 1/8" hole, scan IAC. if still to high (likely) drill 1/64" larger, scan IAC again. Take baby steps as 1/64" larger makes a big difference
IMHO boring a stock TB to 52 is the way to go but you still need to enlarge the stock IAC hole
#5
Launching!
iTrader: (1)
I discovered that my aftermarket 58mm TB had smaller idle passages than the stocker, which caused pegged IAC counts and it ran like crap. I ended up drilling the hole bigger as mentioned earlier, and also milling out the internal passages a bit bigger also. Idles good now with IACs in the mid 30's. That is with the blades fully closed, and all air routed through the idle air passages.
#7
Atlanta
If you have a low idle thing going on than your IAC counts would peg at 160. Use a scan tool to see what they are. If high than drill out the stock hole 1/64" and scan again. If still to high than drill another 1/64" larger. Take baby steps, 1/64" makes a big difference in IAC counts
remove TB to drill....you don't wan't shavings going in intake.
you can also do the "open blades and then clock TPS" method but IMHO the drill mod, especially using a stock TB, is the way to go.
If you have a low idle thing going on than your IAC counts would peg at 160. Use a scan tool to see what they are. If high than drill out the stock hole 1/64" and scan again. If still to high than drill another 1/64" larger. Take baby steps, 1/64" makes a big difference in IAC counts
remove TB to drill....you don't wan't shavings going in intake.
you can also do the "open blades and then clock TPS" method but IMHO the drill mod, especially using a stock TB, is the way to go.
Trending Topics
#9
the IAC at 49 should still idle decent although when you turn on AC, turn wheel (using PS) it could get to pegging them at 160
If you do the drill mod, just one pass with a drill bit 1/64" bigger than the stock hole (1/8" IIRC) should bring them down mid to low 30's
If you do the drill mod, just one pass with a drill bit 1/64" bigger than the stock hole (1/8" IIRC) should bring them down mid to low 30's