Diablosport i3 worth it just to raise idle

[juicedgsr95]

2011 5.3. I got the i3 with the main purpose to disable AFM and raise the idle. Raised the idle 100 RPM and now at idle it is super smooth, no more hiccups while sitting at a light. I am just using the 87 tune for now, may install the 'firm' transmission tune as well. but so far it is working exactly as I hoped. I also may play with the idle and see if +50RPM gives me the same smooth idle.

 

[gooffeyguy]

How old are the spark plugs and wires?

A lot of my rough idle cleared up when I put on new wires

 

[juicedgsr95]

I wouldn't call it rough, but it stumbled sometimes. 140k miles. to try and cure this I replaced all the plugs/wires, cleaned MAF, cleaned throttle body, replaced engine mounts (one had failed), ran injector cleaner, Replaced fuel pump (original failed), new air filter, oil catch can (not sure that matters), changed oil. I chased it but this was a new to me vehicle so replacing this stuff at 140k needed to happen anyway since there was no record of it being done. From all I have read, the 'stumble' at idle is normal since these engines idle so low. watching the idle with a little bluetooth scanner it was around 500 rpm and stumble to 460 rpm.

 

[justchecking]

I also replaced wires and plugs to no avail but using the Diablo to raise idle just 50 rpm eliminated my stumble at idle. After that I replaced maf and o2 and I would be curious of the result but don’t want to change the tune again.

 

[juicedgsr95]

I also replaced wires and plugs to no avail but using the Diablo to raise idle just 50 rpm eliminated my stumble at idle. After that I replaced maf and o2 and I would be curious of the result but don’t want to change the tune again.

Good to know, I will probably drop mine to +50rpm

 

[Dustin Jackson]

@juicedgsr95 Higher idle RPM = higher oil pressure at idle too, something to think about

 

[juicedgsr95]

@juicedgsr95 Higher idle RPM = higher oil pressure at idle too, something to think about

yeah ive noticed that as another positive.

 

[Charlie207]

I'd also procure an in./lb. torque wrench and retighten the intake manifold bolts per the two-stage sequence. I noticed an air-leak that was causing some minor, but wonky, sensor readings.

 

[Doubeleive]

when I first got my 2012 it had a very random stumble, changed the throttle body to a ls7 model and it resolved the issue

 

[gooffeyguy]

Isn't there like a sensor on the throttle body, like TPS or something? Maybe just the sensor was bad