Monsterbox

iTrader: (6)

Installed a new (previously owned) motor, large street port, with an AEM EMS V1 thats been tuned for this motor. T04S, 1680cc/850cc, walbro 400

Car runs flawless EXCEPT, when I first crank up the car it will not idle, car cranks up and then dies. I have to keep the pedal down right after cranking it and get the rpm up to 2k and hold it for about 120 seconds or more. Then the car will barely idle at 500rpm. If i hit the gas lightly it will bog down and stall out until warm.

The fast idle cam has been deleted and there is no adjustable screws on the t/b except for the direct valve adjustment behind the tb elbow. I'v tired to raise the idle via this screw and the idle just bounces.

Car also hesitates like a bitch until its at 160f.

Is there a way to raise the idle via this ECU? Is there some sort of specific cold start learning mode etc?

EB Turbo

iTrader: (1)

There are a lot of adjustments to fix this issue. You need to tune the idle% v target table. You also probably need to do a cold start and adjust the intake air temp offset table and more importantly the warm up enrichment table.

Turning the idle adjustment screw will make things worse if the idle is not adjusted properly in the first place. Start with the idle adjustment screw 2 1/2 turns out and the car needs to be fully warmed up before starting this procedure.

Adjusting the Idle % vs Target table:
The Idle % vs Target table is a simple lookup table: when the EMS is attempting to idle at a certain engine speed, it will begin by using the duty cycle found in this table. The idle feedback settings are used to fine-tune the actual engine speed. The Idle% vs Target table should be adjusted when the engine is warm.

1. Open the Idle>>Advanced Idle template and set Idle FB Minimum to -40, Idle FB Maximum to +40. Be sure to press Enter when changing values, or the EMS will not save your changes.
2. Open the Idle template and set the entire Idle Target Base table to 2000 RPM. The EMS's idle feedback will increase or decrease the Idle Position in an attempt to bring the engine speed to 2000 RPM. Go to the 2000 RPM breakpoint and adjust it so the Idle Learned Value is between -3 and -7%.
3. Set the entire Idle Target Base table to 1900 RPM and adjust the 1900 RPM breakpoint in the Idle % vs Target table, again shooting for an Idle Learned Value between -3 and -7%. Repeat this process until you have adjusted each breakpoint in the Idle % vs Target table.

If you find that you are having a hard time getting idle control to work in 1800+rpm and below 1000rpm you will need to adjust the idle adjustment screw. Here are some more notes on the idle control.

Options-Idle
Hi Idle Car Speed: above this speed, the EMS will attempt to idle at a higher RPM (see Hi Idle RPM Offset). Adjusting this setting may help avoid stalling when the clutch is suddenly depressed at high speeds.
Hi Idle RPM Offset: this is the extra RPM to add when the Vehicle Speed is above the Hi Idle Car Speed.
Hi Idle Wait Time: this is the amount of time to maintain the Hi Idle RPM offset after the Vehicle Speed has fallen below the Hi Idle Car Speed
Idle FB Below RPM: if the car gets "stuck" at a high idle, you might want to increase this.
Idle A/C Load Comp: Adjust this to compensate for the extra load when the A/C compressor clutch is activated by the EMS.

Advanced Idle Template:
Idle FB Minimum: set this to a very low value (-30 or -40) if you have not disabled the fast idle cam in the throttle body. In stock configuration, there is a thermowax plunger that will prevent the throttle from fully closing until the engine warms up. This can increase idle speeds by over 1000 RPM when cold, and the EMS needs to be able to compensate for this.
Idle FB Rate: if the idle feedback is fluctuating wildly when attempting to idle, try a larger number for this setting.
RPM offset vs TPS table: if the fast idle cam in the throttle body is still present, values in this table can cause the EMS to target a higher RPM when the engine is cold. You can compensate for this by decreasing the values in the Idle Target Base table for temperatures below 170F.

Once this is completed let the car completely cool down and you may even want to wait to do a full cold start in the morning. The car should idle very well now and the only thing that will make it not idle well is AFRs. As you see the temp come up in the engine you will adjust the warmup enrichment table to try and keep the AFRs as stable as possible. If the engine does not want to throttle accel very well, once you set the warmup enrich table you can go back on a cold start and adjust the Accel v coolant temp table. In that table you do not really to to be too specific large block sections usually work pretty well.

This should give you a good starting point to getting your issues resolved. Feel free to send me a copy of your map to review. pm me for my email.

EB Turbo

Monsterbox

iTrader: (6)

Holy moly, that was extremely informative. I really really appreciate it. Im having the car tuned by Ray Wilson from pfs in a week and will have him look it over. If things still dont turn out well I may send you the map! Thanks a ton!

EB Turbo

iTrader: (1)

There are definitely people who know how to tune the AEM and there are people who do not. I don't know Ray but If he runs into any issues you can have him contact me. If he tunes for PFS he should be fine.

EB Turbo

Monsterbox

iTrader: (6)

Do you mind pming me your contact info in case we need some assistance? Your time would certainly be compensated. The tune will be on the 18th and im hoping to max out the turbo in the 20s psi w water/meth.

EB Turbo

iTrader: (1)

Not a problem. I don't mind a call before hand just to clarify how to do the boost target comp stuff including the integration of the water meth. You can essentially have the aem trigger the water meth to come on at certain conditions and/or you can have the water meth tell the ecu if it is safe to turn the boost up. This will be a failsafe to prevent the car from running too much boost if the aux injectiin is not working.

EB Turbo