Hi guy's I'm looking for advise on some minor tuning issues i'm having with my new project. The engine is a pontiac 455 in a 76 TA converted to port injection and running a 1227727 ecu and using SAUJP V4 as the basis for the tune. cam specs are .436 .436 lift and 224 224 dur 113 lsa So far im just working on the startup and idle tune, I am seeing in the log that it is regularly bumping in and out of MAP AE and sometimes TPS AE just sitting at idle. what parameter should i be adjusting to correct this? TPro log attatched

 

Shouldn't be getting TPS AE unless the throttle is moving. MAP AE can be caused by a rough idle, be sure that the idle RPM is sufficient.

There doesn't seem to be a dMAP threshold to change. To eliminate MAP AE at idle will need to work on a table or two. Lowering or zeroing the fist entry in this table will help:

; MAP ACCEL ENRICH FACTOR vs DIFF MAP
L8580

Can also try working with the first entry of this table:

; MAP Accel Ebr FACTOR MULT vs TPS LOAD
L859F

As the TPS% should be at zero when in idle.

RBob.

 

Rough idle defiantly can cause the MAP AE to come in/out.
The added "word" in the data stream shows if it is happening.
I think the entry at 52E "Min TPS for AE" may help by increasing slightly IIRC.
If your idle is running rich in CL you may want to reduce the o2 tables by 540-50 (three tables)
There's a thread describing the 02 tables for idle and part throttle.

Link to description of the sheet: https://www.thirdgen.org/forums/diy-...readsheet.html
Protection PW is on the bottom line of the post if you want to modify something else.

Link to the original thread:https://www.thirdgen.org/forums/diy-...ng-points.html
This is in the guide book thread too.
The link to the sheet should still work, if you can't get it post up and I'll get it reposted somewhere.

Also check that the Idle SA Error tables are reduced so idle spark does not fluctuate by more than a couple degrees.
There are two of those tables at 1F0 and 1EB.
One is for advance, the other for retard.
Lowering the correction at small error values can help a lot.
Jp

 

Thanks for the tips guy's i will give these things a try next chance i get to o some more tuning.