Car wants to die

[Spisak_svt]

so I recently started my car for the first time since I’ve been back from deployment and I supercharged it. Every time I start it when it’s at idle it jumps rpms and wants to die. I don’t know if it’s a time issue or a vacuum leak or bad fuel. I’m just looking to be pointed in a direction because I don’t really know what to do from here.

 

[Brutal Metal]

Have the tuner look at the mass air meter transfer curve, stalling is a common problem if not dialed in correctly.

 

[LuuisHernandez]

Does it rev up and drops to like 200 RPM before idling?


Sent from my iPhone using svtperformance.com

 

[old01cobra]

so I recently started my car for the first time since I’ve been back from deployment and I supercharged it. Every time I start it when it’s at idle it jumps rpms and wants to die. I don’t know if it’s a time issue or a vacuum leak or bad fuel. I’m just looking to be pointed in a direction because I don’t really know what to do from here.

First off what year mustang? Second gen s197?

 

[Mojo88]

As you imply, look around for obvious vacuum leaks. Then get some fresh gas in there, depending on how long it's been sitting. I had similar issue with my supercharged 4.6L and it totally cleared up once I THOROUGHLY cleaned the MAF sensor (using the appropriate cleaner, of course). My MAF looked fine to the naked eye, so I was surprised (pleasantly) when the car started running good again after cleaning.

Good luck, and thanks for your service!

 

[Spisak_svt]

Does it rev up and drops to like 200 RPM before idling?


Sent from my iPhone using svtperformance.com

Yes

 

[Spisak_svt]

First off what year mustang? Second gen s197?

It’s a 2012 5.0

 

[Spisak_svt]

As you imply, look around for obvious vacuum leaks. Then get some fresh gas in there, depending on how long it's been sitting. I had similar issue with my supercharged 4.6L and it totally cleared up once I THOROUGHLY cleaned the MAF sensor (using the appropriate cleaner, of course). My MAF looked fine to the naked eye, so I was surprised (pleasantly) when the car started running good again after cleaning.

Good luck, and thanks for your service!

I looked around for vacuum leaks last night and could find anything im gonna get some new gas in it today what did you use to clean maf?

 

[Spisak_svt]

Have the tuner look at the mass air meter transfer curve, stalling is a common problem if not dialed in correctly.

I’m going to datalog it at idle today and send him the file see if he can find anything

 

[Mojo88]

..... what did you use to clean maf?

Mine is "CRC Mass Air Flow Sensor Cleaner", but you can go to virtually any store that sells auto supplies and look for can that specifically says MAF cleaner on it. Make sure you use ONLY "MAF Cleaner".

It took me two cleanings before I noticed the difference. First cleaning, I only sprayed two or three shots. But second cleaning I hosed it nine or ten times, then let it dry, and reinstalled.

Don't touch any of the little wires!

 

[Spisak_svt]

Thanks man I’ll give that a try today and let y’all know how that went

 

[LuuisHernandez]

Did you unplug the battery at all? I️ had the same issue after unplugging the battery and just had to drive it and kind of push it.


Sent from my iPhone using svtperformance.com

 

[LuuisHernandez]

I️ also thought it was the MAF but it wasn’t. Try driving it around.


Sent from my iPhone using the svtperformance.com mobile app

 

[Spisak_svt]

I️ also thought it was the MAF but it wasn’t. Try driving it around.


Sent from my iPhone using the svtperformance.com mobile app

It’s throwing a code P0103 which is something to die with the maf

 

[Spisak_svt]

Did you unplug the battery at all? I️ had the same issue after unplugging the battery and just had to drive it and kind of push it.


Sent from my iPhone using svtperformance.com

Yeah unplugged the battery during the whole process

 

[LuuisHernandez]

Have you tried to drive it? Clean your maf sensor regardless. Or even try revving to about 2000, hold it, then to 2500, hold, and so up until about 5000. May need to readjust the MAF by doing that after unplugging the battery. But definitely try driving it. I️ had basically the same symptoms.


Sent from my iPhone using svtperformance.com

 

[Need 04 Wine]

https://www.obd-codes.com/p0103

you said FIRST time?
If so 99%(*1) sure its just dirty MAF.
Could be oil from the new filter, fingers touching it when transferring to inlet tube, dust etc.....

simple and easy and cheap to clean

good luck

(*1)
percentage indicated is subject to change without warning dependent on the outcome/resolution of stated problem

 

[Spisak_svt]

Have you tried to drive it? Clean your maf sensor regardless. Or even try revving to about 2000, hold it, then to 2500, hold, and so up until about 5000. May need to readjust the MAF by doing that after unplugging the battery. But definitely try driving it. I️ had basically the same symptoms.


Sent from my iPhone using svtperformance.com

I data logged it and sent to my tuner haven’t driven it yet maybe tomorrow. I live in Washington so it rains a ridiculous amount and I have drag slicks on right now so I’m not trying to drive it in the rain.

 

[LuuisHernandez]

I️ have a video on my old phone of what was happening so I’ll try to get that and post it for what it’s worth. Also doesn’t hurt to clean maf, like others are suggesting.


Sent from my iPhone using svtperformance.com

 

[Bill@HPTuners]

What supercharger? Who's doing the tuning?