Custom Tuning Step 1 of 4

by Michael Decipha Ponthieux
Last Updated: 2017-08-20

This page ONLY applies to those whom were directed here AFTER receiving a custom tune from me.

DO NOT, continue reading this page until AFTER you have read over and verified the Pre-Tune Information and Initial Tune Instructions

If you have a quarterhorse I highly recommend using TunerPro RT, if you don't have it setup yet the Getting Started Write Up will give you all the details.

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Load Tune & Verify Tune Loaded Correctly

First and foremost load in your startup tune before doing anything.
Make sure you ALWAYS VERIFY that your tune is for you, the first letter will be the initial of your first name.
For example: MPON_170220a.bin
MPON would be for Michael PONthieux, YYMMDD and the revision for that day a,b,c,d,e,f,etc...
When receiving your tune verify it is for you, if not, DO NOT LOAD IT.

Once you have your tune loaded and turn the key on you will hear the fuel pump prime and shut off.
Then set the base fuel pressure to either what we discussed (typically 55psi if you have less than 60lb injectors).
Next verify the ignition timing is at 10 degrees btdc with the spout plug removed. This is VERY IMPORTANT otherwise you can damage the engine.
For EEC-Vs that have been converted from returnless to return style, the fuel pump will run constantly with the key on unless I have written custom code and remapped an unused output pin to control the fuel pump correctly. In these cases, verify the ecu is communicating correctly by starting the log with the key on and pressing the throttle to the floor to make sure the datalog shows you have entered WOT.

When you load the tune in and fire up the engine on the startup tune it most likely WILL NOT BE HAPPY so you'll need to do EVERYTHING you can to keep the engine running until it gets up to warm operating temperature (warmer than 170* F on the ECT sensor). Don't worry about how she starts cold or cold idles or how any of that is since it means absolutely nothing, cold enrichment and startup can ONLY be dialed in AFTER the fuel and idle has been dialed in correctly.
If the engine doesn't fire up on the first crank, repeat a 2nd time, if it doesn't fire up on the second crank, then HOLD THE THROTTLE TO FLOOR == WOT to enable flood-clear mode, this will cause the ecu to shut off the injectors. The ecu is pre-programmed to disable the injectors when the pedal is held WOT during startup to prevent flooding. Flooding the engine with fuel will wash down the rings and can destroy a new engine rather quickly. DO NOT do excessive cranking.

Until we get the fuel dialed in there are a couple things you do not want to do

Verify its not overly rich

If you have a wideband watch the gauge and make sure it is LEANER than 0.82 lambda after the engine has been running for at least 2 minutes, if you don't have a gauge then pay attention to the hegos. IEGO1 voltage should be reading less than 0.800 volts after the engine has been running for at least 2 minutes. If the hego voltage is stuck at 0.700 volts or higher and is not switching (jumping above and below 0.400 volts) shut the engine off.

If the engine has been running for longer than 2 minutes and the wideband is RICHER than 0.82 lambda then you will need to shut the engine off immediately so i can send you a new tune with less fuel in it, again if you don't have a wideband make sure the hegos are not STUCK at a voltage greater than 0.400 volts.
Note: If you feel up to it, you can reduce the maf flow at 400 imaf counts on down by multiplying the flow by 0.85 this will expedite the process, be sure to post your modified tune with your datalog if you do so.

Don't be worried if the wideband reads lean at idle, its safer to be leaner than richer, ideally we want it at 1.000 lambda , but if it idles at 1.23 lambda thats perfectly fine too so don't be alarmed
a lean mix can only harm the engine when your at more than half throttle, otherwise at idle being lean is perfectly fine and won't hurt anything.

WARNING: The check engine light should not be on while tuning, if the check engine light is on while the engine is running then SHUT THE ENGINE OFF IMMEDIATELY. If the check engine light is on with a tuned vehicle that means the ecu has detected a MAJOR PROBLEM and you must pull codes immediately to find out why. Note: The CEL will come on at key-on and go off during cranking, that is normal operation.

Once she gets up to warm operating temperature you want to get the ecu into closed loop, it should go into closed loop on its own within' 2 minutes and start adjusting fuel for you, but
if it doesn't you may need to rev the throttle a few times in order to get the hego's to switch to enable closed loop.

You can tell if your in closed loop because LAMBSE1 will be jumping around increasing and decreasing its value,
if LAMBSE1 stays at 1.000 then you are in open loop.

Correctly set the throttle stop according to "IPSIBR"

Once the engine reaches a warm non-surging idle, look at the IPSIBR payload on the dashboard.
if IPSIBR is greater than > 0.050 you will need to unplug the tps sensor connector and OPEN the throttle stop on the throttle body to allow the engine to get more air to reach idle.

If IPSIBR is at 0.0000 and the engine is idling too high or (greater than 800 rpm or the substitue idle rpm we discussed -NUBASE idle rpm value), then you will need to unplug the iac and DECREASE the idle stop screw to get the engine to idle down.

In either case, do not forget to plug the throttle position and iac sensors back in.
Note: You must always remember to unplug the throttle position sensor anytime you OPEN the throttle set screw, otherwise the ecu will set the part throttle flag and go into dashpot and part throttle spark control.

If you had to OPEN the throttle stop, be sure to unplug the tps before opening the stop and replug in the tps after adjusting.

For the first log the engine must reach a warm not-surging idle, so once the engine gets up to operating temperature (after 15 minutes of idling from cold start) , let it idle on its own (if it can) do not hit the throttle pedal and start logging.

Log at least 75 seconds with the engine at a stable warm idle with no throttle movement, make sure the ecu is in closed loop, this can be observed by LAMBSE1 jumping around with its value increasing and decreasing AND NOT STUCK at one set value.
During this time while your waiting, I highly recommend checking for any coolant, oil, powersteering, or any other leaks underneath the car, pop the hood and make sure nothing has come loose, just give it a good double over as you will need to drive it. Double check the brakes and lug nuts are intact and that the brake fluid reservoir isn't empty.

Step 1 LOG - Fuel Error - Hold every +50 ad counts (0.25 MAFV) increments for fuel error

Any time an engine is started it takes approx 3-4 minutes for friction and puddling affects to clear out and allow the engine to stabilize. Make sure the engine has been running at least 3-4 minutes from a warm startup before doing the imaf steps otherwise the fuel errror will be incorrect. So if for any reason you had to shut the engine off, be sure you let it 'clear out' before doing the imaf error log below; otherwise the fuel error will be incorrect. Verify the ecu is in closed loop before attempting to work the imaf steps.

If you have a project vehicle that cannot be driven currently, you may perform the following at idle with the vehicle stationary but ONLY if your setup is an N/A - Naturally Aspirated engine (no supercharger or turbo), this is as a last resort only and not recommended at all.

If you have a boosted engine (supercharged/turbocharged) the following MUST be performed while the engine is moving and loaded regardless.

Finally, Nows the Time - "The Step 1 Log"

For the step 1 log you must lightly drive the vehicle to hit each imaf point. This can be done on a non-busy street or in your own driveway if its lengthy, I recommend slightly riding the brake to help load the engine and prevent excessive speed, you may also set the handbrake (e-brake) slightly to help load the engine.

Once she's in closed loop at a warm idle watch the IMAF (maf voltage ad counts) on the dash and use the throttle pedal to hold the imaf at each 50 ad count increment, if you are idling at less than 200 imaf ad counts, lightly tap and hold the throttle until the imaf reaches the next 50 imaf increment, either 100 counts, 150 counts, or 200 counts, hold it steady there (ex: at 200 cts) for 10 seconds, then slightly apply a little more throttle and hold it at at the next +50 ad counts increment (ex: 250 cts), again for at least 10 seconds, then repeat again for 10 seconds at the next +50 cts increment (ex: 300 cts), hold it for 10 sec, repeat this in 50 ad count intervals going up as high up the IMAF as you safely can or feel comfortable doing. Ideally it would be best if you can reach the highest imaf that corresponds to the rpm you will spin the engine up to (for ex: do not exceed 6k rpm or so to reach any higher imaf points). After you have reached the highest imaf point you feel comfortable at let off the throttle and let her reach a stable idle for at least 30 seconds.

Then stop the log and post it in your Private Progress Thread
After I review the datalog, I'll post back with an updated tune so we can proceed to step 2

If you have any issues along the way don't hesitate to shoot me a text or buzz my tele at: five zero four six zero six zero five three two

Continue to Step 2

Understanding Step 1 Changes - FYI
I usually start all my custom tunes from my base tunes, I then typically apply the following changes for starters.
Base Fuel TableI null ==1.000 so interpolated lambses don't skew my corrections
WOT Multiplierassign all 1500+ rpm to wot lambda (just in case someone goes WOT its not lean)
FN320AI max it out so open loop is forced only by tprel while i dial it in since fn035 won't be dialed in yet
WOT BreakpointI kick it up along with the OL breakpoint scalar so i can see how the fuel trims up top
Hego Min SwitchesI set it to 1 switch so it goes into closed loop quickly
BYPLESI kick it up to 60 sec for initial tuning so the hegos have 60 sec to fail if the fuel is too far out and it can't switch in a shorter period of time

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