Bhead32

I have had my 87 octane tune from brenspeed with the C&L CAI intake for a few weeks now and have loved it. Two days ago I decided to fill up with 93 octane and loaded the 93 octane tune. Started the car and drove around for 10 min before going home. I didnt drive the car the next day but I tried to start the car today and It wont start! I turn the key and the dash/speedo lights flash on and off very fast. I tried to plug in the SCT tune to change the tune or read what was going on but cant because when i turn the key to the on position the car does light flashing.

Whats going on with my car!? I read that if you take it to the dealer and they reflash the computer it may not start. But I have an 05 which is not supposed to have this problem, and I didnt take it to the dealer.

Anyone know whats wrong?

NJ3

Check your battery voltage first .

Bhead32

how do you check the voltage if I cant get any info from the SCT?

mot250

Try the old fashioned way, at the battery terminals, with a volt meter.

Odd series of events, though. I've had no problems with my Brenspeed tunes. I've been mainly running the 93 octane tune but I have switched occasionally to the 91 and the 87 (ick, she seems slow!) and back to the 93 with no problems.

Have you tried calling Brent? He has been very helpfull whenever I called, though most of my calls were for upgrade advice and orders.

TacoBill

+1

If you still have the stock battery, it may have taken a dump.

Bhead32

No its a fairly new battery so it shouldnt be dead but I'll check the voltage when I get home. Yeah I'll call brent and see if he can help me out.

You're not supposed to go back to the stock tune before you switch tunes are you? Because I went straight from the 87 to the 93.

Bullitt995

Better way to check battery voltage is by touching the negative terminal with the tip of your tongue. If you wake up in the hospital, your battery is fine. If not, replace battery and repeat until desired results are met. Atleast that's how I do it.

mot250

No, you don't need to go back to stock between tunes. Sounds like you've only had the CAI on for a little while. Recheck your CAI installtion for loose parts including the MAF sensor wiring connection. But I don't think those would cause the extent of your issues.

mot250

That explains a lot!

Mustang85

Sounds like a battery to me too with the "flashing" problem. The past few cars with a near dead battery I've tried to start did exactly what you described accompanied with a clicking sound. I haven't had this problem with my mustang, but have come across several stories on the forum with people having similar problems. People with relatively new mustangs won't start the car for a couple days, and next thing they know their battery is dead. It's supposedly a pretty common problem. Try jumping your car off of a friend or neighbors car!

RKNMACH

Check the cables to see if you have good contact with the terminals.

Bhead32

which cables are you referring to?

wallace

did the car flash fast and completely die if so you may be dealing w/ a dead batt. or, does it continue to flash repeatedly while the key is in the on position, in this case you should call brent.

NJ3

He's referring to the Black and Red cables that attach to the top of the battery. If they're loose they can cause the same symptoms as a dead battery.

mustangdaren

Interested to see what the outcome is. I just installed a C&L with SCT from Brenspeed two weeks ago also but I went straight to the 93 tune. So far no problems.

wallace

orignal poster... remove your battery cable for 20min. and put them back on and rethighten. this should reset your car, if the batt. is'nt dead.

Bhead32

Thanks for all your help guys, it turns out it was the battery. I jumped it and it seems to be working again. But for some reason, the driver side window will not raise automatically when I try. It will go down automatically if I push the switch down all the way but will not come up the same way. Is there a switch that was switched off when this happened? Ive never heard of something like this.

mustangdaren

I don't recall mine ever going up automatically, only down. I might have to go out and check it again just to see.

ski

If your car is still under warranty, then have the dealer check the battery. They can determine if it's bad, and replace it at n/c if it is.
Otherwise, one day you may find yourself stranded in the middle of nowhere.

RKNMACH

The battery cables. A loose connection will cause problems.