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· Registered
1,503 Posts
Discussion Starter · #1 ·
The problem started after a MAFT Pro and Q45 TB install. The car will start up fine but will not idle. The MAFT Pro was installed and set up according to the manual included and the TPS was wired according to the write up in the FAQ section.

The car seems like its "hunting" for the correct idle, like it does when the AFM is disconnected, and the AFR is all over the place. The MAFT Pro's set up:

Ver. 5.08

Config mode
Veh sel: 0
# of Cyl: 6
Displ: 3.0
Airfl mode: Speed den.
MAP source: GM 3bar
Load srce: use MAP
Baro mode: Read at key on
F out mode: Supra MK3
V out 1 mode: Set max
V out 2 mode: set max
AFR srce: Innovate LC1
F in mode: none
AUX 1 mode: aux trig off
FlowErr mode: SD/MAF

System Setup
SPK base: 0
Use VE table: 2
FE smooth: 30
AF TRdelay: 0
TM correct: 1.27
TM base: 0
F out max:0
Hi Ld pt: 143
Mi Ld pt: 100.1
Lo Ld pt: 36.4
Afterstart: 0
V out 2 max: 3.600
V out 1 max: 2.500
Main scale: +2.5

TPS Enrich: .50
TPS Decay: .80
TB size: 7
MAP enrich: .4
MAP Decay: .80
MAP TPS min: .500

MP is ~83 at key on, and bounces between 30 and 60 at the extreme rough idle.

My mods:
550cc injectors, FFIM w/ Q45 TB, Aeromotive AFPR @ 43PSI, Walbro 255

Here's a short video of the problem:

Thanks for any help guys.

· Registered
19 Posts
I have a similar problem, also using MAFT Pro. It is however a lot more random as some time the engine will start up just fine and settle at 800RPM, most times however it will bounce from bear stall and idle rough at about 500 RPM. Still working on it.

· Registered
1,503 Posts
Discussion Starter · #4 ·
Map sensor is placed on the firewall where the alarm horn was with a vacuum line off the bottom of the intake manifold.

FP is with the line off and I read somewhere thats what its supposed to be set at. Am I wrong?

I plugged the hose off the isc valve and that helped.

I am getting code 14 if that makes any real difference.

· Where to now?
919 Posts
everyones system runs a little different. since you installed the 550's you went -20 accross the board for the increase in fuel correct?

with the vac line off your fpr should read around 30. i was incorrect in telling you mine was 37. it is actually 27 when idleing with vac line on.

the code 14 i beleive is normal assuming you wired in the timing control. b/c it cuts the signal to the ecu and the maft is now controlling it. did you use this diagram?

***edit: check out or lots of setup info.

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