Road Tuning: Step 6 - Idle control
Watch This Course
$229 USD
-OR-
Or
8 easy payments of only $28.63
Instant access. Easy checkout. No fees.
Learn more
Step 6 - Idle control
02.35
| 00:00 | - Before we go any further we want to get the engine to a point where it's going to be idling happily by itself and again, because this is a plug-and-play we've already got numbers in the ECU base map that actually do a pretty good job of this, so our work's mainly done. |
| 00:15 | I just want to talk through the adjustments that are necessary though. |
| 00:18 | If we go into the idle speed control menu this gives us all of the parameters we need to adjust. |
| 00:24 | The actual idle speed control system on this car, it uses the electronic throttle body for idle speed control. |
| 00:31 | Now, the first step with setting up idle speed control is to make sure that our idle target is correct. |
| 00:37 | So we've got our 2D table of idle target versus engine coolant temperature and you can see down at low engine coolant temperatures from a cold start I've targeted 1200 rpm. |
| 00:50 | In our normal operating temperature, we're targeting 950 rpm. |
| 00:55 | And I've just done a smooth interpolation between those numbers. |
| 00:59 | So that's the first step is to make sure we've got realistic numbers in that table. |
| 01:04 | The next step is to change or set our base idle position table. |
| 01:10 | So, this is the table, in this case of throttle position opening. |
| 01:14 | And you can see we've got down at cold temperatures, we've got more throttle opening and it gradually decreases until we get up to our normal operating temperature where we've got 1.1%. |
| 01:26 | Now this table needs to be adjusted basically to give good idle speed control right through the cold start enrichment modes. |
| 01:35 | Make sure that wherever we are in the engine temperature, we can start the engine and it will idle properly. |
| 01:41 | Now, we're using this idle control and idle set up to make sure that the engine can be made to idle smoothly by itself. |
| 01:50 | This is a completely stock engine, so there was no surprises that it does, but on modified engines we quite often find that won't be the case. |
| 01:58 | So things we want to be looking for here is that the engine can be made to idle at a smooth rpm. |
| 02:03 | So here we're holding at a nice consistent 950 rpm which is our target. |
| 02:07 | You can see we've got good engine vacuum here. |
| 02:10 | We're pulling around about 43 kpa-45 kpa of vacuum. |
| 02:15 | If I was seeing numbers around about 80 or 90 kpa that would indicate we may have a vacuum leak or maybe a cam timing issue. |
| 02:23 | So if we can get the idle speed stable like this we know that the engine is mechanically sound and we can then move on to actually tuning the engine. |
