Hi all. My car runs great, most of the time: SC'd and tuned with EMS, strong smooth pull under acceleration. However, I've been doing a lot more city-driving these past couple of months and the car would occasionally just die when I'm in neutral (e.g., cruising towards a stop light or down a hill).

If it dies and I am at a decent speed, I would just restart the car while in motion. But there have been a few times when I would have to turn on the hazards in the middle of the road to start the car because I would be at a near-dead stop. Obviously, this is not cool.

So any thoughts as to why this happens? I notice that this happens about once every 2-3 days while driving to work in the morning (weather would be in the 60's). Less often in the evening. I'd appreciate your input before I contact my mechanic.

TIA!

 

Possible faulty map sensor?

 

Do you have a laptop? Try hooking up to the AEM and monitoring what's going on...I had the same problem on my ITB's...my AFR's were too lean in the 20% to 40% load cells from 1500-3000 rpm, and the EMS couldn't recover from a sudden load drop (shifting to neutral, or waiting too long to downshift)...normal cruising your in completely different fuel and timing cells on the map...up in the 80-90% cells somewhere. When you pop it into neutral, it removes almost all the load off the engine for a few seconds while the rpm's drop....the EMS tracks down very low onto the fuel and timing maps...it's down there where your problem is.

 

Tune may not be appropriate for the weather.
Also, check your plugs.

 

I have had the same problem with my 01. Normal driving fine get into town and hit a light it dies. I have checked map sensor time and time again and it be fine. Like ckit said check your plugs. I have noticed in the past when mine starts doing that new set of plugs helps tremendously. Also try checking in your fuel trims in the EMS system. Last time I just called my tuner for a house call and cleared it up and no problems since.
Good luck,

Spiffey

 

Thanks everyone. That helps.

 

Moving to FI