Sschmuve1

iTrader: (1)

So a weird thing happened yesterday. I start the car in my driveway, and it stumbles and idles roughly at a low 500 rpm. It's occasionally done this before, so I don't think much of it. After driving slowly through the neighborhood a while it seems okay. I get to the main road, gun it a bit through first and second, let off, shift to 5th, cruise for a few seconds, turned the lights on and bam....no power with a check engine light. It was like the light switch turned off the car. Strange. This lasted only a few seconds, and the engine restarted.

91 octane plus Arizona heat (104ish)?

All stock except the Cobb AP stage 1 tune.

Bobster22388

iTrader: (13)

Possibly a loose battery connection? I know it's probably very unlikely, but couldn't hurt to check. Does sound very odd though...

Xtremist

iTrader: (1)

I use to have a ford racing chip in my Mustang which caused it to act like this, could be the tune???

dek0026

it restarted on it's own?

dxbtune

^ from what I understood, what happened is like jump starting a car but at a much higher speed.
Or he pushed in the clutch and cranked to get her fired up again. I doubt it just started on its own i.e starter motor.

dek0026

well what he described could mean that the engine didn't totally stop but dipped real hard into low rpms and the back up again. that was what i was trying to figure out.

Sschmuve1

iTrader: (1)

It seemed like after it died ( in gear, clutch still engaged, ignition still on), it push started itself.

I'm thinking this may have been the cause:
-After shifting from @ 7000 rpm immediately to 5th, the rpm abruptly decelerated.
-I press the accelerator, (ecu expects 3rd gear based rpm)
-Momentary flood at the exact time of a voltage dip of the lights being turned on.

Any tuners out there think this is possible?

bryanv

iTrader: (6)

Wow never heard about an issue like that before. Sounds pretty dangerous man, hope you figure the problem out!

stikllr13

iTrader: (1)

This happend to me a lot actually, only once while moving but 50% of the time if I turn on my headlights it surges the engine really badly. I just started turning my lights on before I turn the car on. Problem fixed lol

Evolution10GSR

It could have been the Evo went into limp mode. Like you described, you were gunning the car at high RPM.

churbo

iTrader: (2)

Weird. How long after you shifted to 5th did you turn the headlights on, was it instantly or was it a few seconds.

Hiboost

iTrader: (9)

I've done the 1st to 3rd gear shift oocasionally but I would probably avoid a double gear jump like that especially when the car is still warming up and you are bogging the engine. Granted you don't want to be revving it past 4k until it warms up but running too low RPM's means less oil pressure and more stress, keep it between 2000-4000.

There is an Evap Map #1 that kicks in much leaner AFR's during warmup mode between 10% and 90% load from 1500 to 4500 rpm's. It's possible that the car almost stalled itself right as it was trying to target 19.8 AFR as you shifted to 5th and bogged. I would say just avoid that combination and you should be fine!

I'm pretty sure that map can cause some hesitation feeling during a cold start in the morning. What is the primary function of leaning out the mix that much during warmup and can I safely reduce the severity of the leaner AFR's it's trying to reach?

novaspyder87

thats nothing lol.....each time I push my car to over 230kph....if I go to neutral the car shut off.....I was so scared one time...Ive done a pull from first to fifth and went into a big left curve at more than 180kph...and while in the curve BANG..nothing.....so I had to take the curve with my arms(freaking tough).

yeah I know you say,why you havent drop the clutch to make it start again....well I was too surprise too make something....my fault.

I think its due to my AMS intake....without a heatshield....and a tune.lol. good luck with your problem.

by the way.....almost impossible that the problem would me the battery...if you think its your light...it would be the alternator...not the battery(which only starts the car).

chriswolf81

iTrader: (3)

same thing happened to me yesterday. It was just getting dark so I did not turn lights on until like 5 min of driving. I had just shifted into 5th, when I turned them on.

Warning tone, the car felt like a jolt went through it, RPM drop and then caught themselves. Info screen read "check something". After that all was fine.

Very strange thought maybe it had something to do with the prosport gauge being hooked to the headlight switch in fuse box?????

ak47m203

maybe the MAF sensor.