Help with FAST ECM and idle problem
Thread Starter
Instructor
Joined: Mar 2002
Posts: 176
Likes: 0
From: Brentwood Essex
Help with FAST ECM and idle problem
Hi Guys,
After fitting the FAST several months ago, I've spent many happy hours tuning, and have now got a nice, economical and emission legal cruise, and the fuelling more or less dialled in across the rev range. The FAST with wideband option is well worth the money, as I did all this witout going near a dyno! However, I have one problem that I just can't solve:
When I put the car in drive, she stalls...everytime! I have to goose the gas and bring the revs up to about 2000 in order for her to keep running. Once she is in gear, I can almost immediately let off the gas, and the idle drops to about 600, then recovers to the commanded 820.
I've been through all the documentation I can find, and all the parameters in the FAST software, and I cannot see what I have to adjust to cure this. The only thing I haven't tried (because it only just now occurred to me!) is to richen the fuel map for the 600-800 rpm range - ie where it doesn't usually go. Perhaps that bit of extra fuel when I engage drive will keep her running long enough for the IAC to motor out and bring the revs up again?
Any help or advice anyone can offer would be appreciated.
TIA
Steve
After fitting the FAST several months ago, I've spent many happy hours tuning, and have now got a nice, economical and emission legal cruise, and the fuelling more or less dialled in across the rev range. The FAST with wideband option is well worth the money, as I did all this witout going near a dyno! However, I have one problem that I just can't solve:
When I put the car in drive, she stalls...everytime! I have to goose the gas and bring the revs up to about 2000 in order for her to keep running. Once she is in gear, I can almost immediately let off the gas, and the idle drops to about 600, then recovers to the commanded 820.
I've been through all the documentation I can find, and all the parameters in the FAST software, and I cannot see what I have to adjust to cure this. The only thing I haven't tried (because it only just now occurred to me!) is to richen the fuel map for the 600-800 rpm range - ie where it doesn't usually go. Perhaps that bit of extra fuel when I engage drive will keep her running long enough for the IAC to motor out and bring the revs up again?
Any help or advice anyone can offer would be appreciated.
TIA
Steve
Racer
Joined: Oct 1999
Posts: 467
Likes: 1
From: Lufkin tx
Re: Help with FAST ECM and idle problem (steveelsbury)
Go to the idle settings menu. I think there is a configuration tab. Click on this. You want to increase the P-gain and D-gain. Play with this and it will idle. Let me know if you need any more help.
Burning Brakes
Joined: Apr 1999
Posts: 758
Likes: 1
From: Cumming GA
Re: Help with FAST ECM and idle problem (steveelsbury)
Click on View
Click on Idle Functions
Start IAC position versus Coolent Temp.
This graph should be 204 @ 16 and 52 @ 254
Then Check Idle Speed, should be around 900RPM at around your operating Temp.
Now if this all looks good, you check if the criteria is met and if not, adjust the TB plates and let more air in that way, so the IAC does less work. The the Iac Opens slow compared to the throttle plates. The IAC may be already open too much to maintain your set parameters.
If your interested Email me your CCom File and I'll take a look at it.
John
Bowtie8@comcast.net
Click on Idle Functions
Start IAC position versus Coolent Temp.
This graph should be 204 @ 16 and 52 @ 254
Then Check Idle Speed, should be around 900RPM at around your operating Temp.
Now if this all looks good, you check if the criteria is met and if not, adjust the TB plates and let more air in that way, so the IAC does less work. The the Iac Opens slow compared to the throttle plates. The IAC may be already open too much to maintain your set parameters.
If your interested Email me your CCom File and I'll take a look at it.
John
Bowtie8@comcast.net
