84 cross fire running rich at idle

[1project2many]

has any one successfully upgraded ECM on the 84 Crossfire injection?? I know no one likes them

I started with an 83 5.0 F car auto trans ecm and calibration, then switched to an 84 5.0 F car ecm, then switched to a 1227747, and currently run a 1227427.

fuel pressure is @13psi

Changing fuel pressure always made a large difference when I was using a stock ecm. Generally I kept pressure around 10 psi back then.

starts out with low idle the as it warms up the rpm increase to 1200 and that is where it stays

Have you balanced the throttle bodies yet?

[Gator]

Thanks 1project2many, I am curious about the difference between 1227747 & 1227427?
The fuel pressure @13 has not been changed at least since I have owned it
as far as balancing throttle bodies, do you mean the IAC's or mechanical? I have tried to balance the IAC's but yesterday I noticed a whiney Squeal coming from top of engine.
Im thinking I have a problem with one of the IAC's , I have the original ones to install and see if the noise goes away.

[Gator]

I did check into balancing throttle bodies and no I have not done that. I am curious if I can use the multiple vacuum gauges I have to do that

[Gator]

well i did the mechanical balancing of throttle bodies, I drove the car with BPW at 124 and it sneezed And coughed , set to 115 and no sneezing but backfiring out of exhaust(new).
I thought I had some data but i figured out I needed to push record button (duh) anyway, I went thru the throttle bodies again late this afternoon and noticed BLM was at 121, int was at 128, then went into closed loop and BLM fell to 108 and idle went to 850 , I should be able to post data a little later this week depending on weather.
Thanks Guy's for your help and patience .
I do have some data but from yesterday @ Idle only.

[dave w]

Closed Loop BLM's above 128 are lean.

Closed Loop BLM's below 128 are rich.

Most TBI computers will "lock" the BLM's @ 128 until closed loop.

The acceptable BLM "averages" range is between 123 ~ 133.

Course tuning typically involves adjusting the Base Pulse Width (BPW) so that most of the BLM's are between 113 ~ 138. Fine tuning typically involves adjusting only the VE table so the BLM averages are between 123 - 133.

dave w

[Gator]

Hey Dave W, thanks for everything,
But this conversion is driving me nuts, no mater where I set BPW the Idle is surging and high (1200), and in C/L the BLM is at 108 I have used the calculator for BPW and from what I have learned the flow rate should be 68/67 between front and rear injectors. which would give a BPW of 121/123. Currently set to 135 ( default). question would be is there any IAC adjustments due to using two IAC's instead of one(typical TBI)

[dave w]

I found the Ebay auction pictures very interesting! https://www.ebay.com/itm/37380293384...BoCJTYQAvD_BwE

Only One TPS and One IAC for both Throttle Bodies.

dave w