coastalS197

Hey all,
(* after searching forum didn't see anything that touched on this exact issue )

Firstly, any and all help is appreciated.

I got a 07 mustang GT, w 100k. Battery is approx. 6 months old.. maybe less.

Drove car last week 'check charging system' appeared in the display. This indicator went away, then i pulled in the parking lot and sat at idle and the radio turned off, when trying to turn it on it indicated there wasn't enough charge in the display on the radio. Then various blinking etc. of random indicator lights... the car cut off and eventually didn't even have enough charge to roll up the window. Had a buddy jump the car and attempted to drive and it died fairly soon after charging it.

Shop I had it towed to, said the alternator was shot. So I did a 'by the book' install of the alternator ( making sure to disconnect neg. battery terminal to avoid an electrical problem nightmare).

According to the electrical guage the car is getting a good charge. Where as before ( w out new alternator ) the charge would be smack dab in the middle of normal on the guage and then quickly die off...

Now ( after new alternator ) the needle is a little more toward the positive end.

But now, the car has a bit of a sputter. It at times is hard to distinguish and is exaggerated by putting giving the car extra gas in a higher gear then it needs to be in. But it also has a slight sputter ( maybe a miss? ) when sitting at idle that is very light. Then, this morning it appears that once i get it revved up past 4 1/2 rpm the check engine light flash's. When i turn the car off it goes away and will re-appear when i rev it past that mark again.

Anyone have any idea's or experienced this issue?

my Ideas:
- bad alternator right out of the gate?
- spark plugs ( factory still... i know .. i need to replace em )?
- a coil pack got messed up when the car had little to no charge?

karman

Plugs should be on your list no matter what.
Most cars built before 2008 have an unusual spark plug and head design.
Read this first:
2008_TSB-Mod_Motor_Spark_Plugs.pdf

cave diver

Is it throwing a CEL?

karman

Read the post.
He needs to go to a parts store that reads them for free and rev the engine, I guess.

coastalS197

Thanks Karman & Cave Diver,

Well i went and got the cel code checked. Its throwing P0305: 'cylinder 5 misfire'

As a response to that a bought a coil pack and replaced the pack on cylinder 5. This feels like it has made the misfire less recognizable and now the check engine light doesn't come on. But still when I'm sitting at idle i can fill a light misfire.

I'm going to replace the spark plugs and wires next.... If problem still exists anybody have any other experience in solving problems that throw that code? ( P0305 ).

& anybody experience any issues with replacing the spark plugs? ( thanks karman for the ford doc detailing spark plug replacement issues on these cars ) Any other advice to avoid problems.... I woulda had know idea had I not seen that doc.

Thanks, and all help is appreciated.

ford4v429

after a dead battery, mine went outright goofy...idling from 500~2500, stalling...

unhook the battery to clear anything its 'learned'(leave unhooked for a while or, I just ground out the red wire after unhooking battery and everything reset). hook it back up, take it on a short drive0- get on a road that you can hit 60+ on, and after getting above 60, lift off the accelerator and let engine braking only reduce speed to under 40- repeat 3 times. I found a thread that explained this is how the engine controls map out the crankshaft position sensor pulses, to eliminate any error due to production tolerances, and it fixed mine right up.

what screwed mine up was, I put a battery in, drove around(non highway) for a week, then took it to work one day on the highway- nonstop, exit ramp is right at works driveway- so when I coasted down the first time I had it above 60, was at works driveway- and as I slowed down I pressed the clutch...the car stalled in the parking lot for the first time ever, then had the crazy idle when I left work...apparently shortcutting the deceleration by pressing the clutch, the ecm mapped bad data and held it- the car would barely run...after reading up on it, cleared/drove it 'properly' above 60, coasted under 40 and immediately it was 100% back to normal. simply clearing it fixed the idle, but it didnt get normal full power back until after the 60/40 thing...dont cost anything to try.

Glenn

does your battery have a full charge now?

coastalS197

Hey all,

Problem solved. Ironically a spark plug went bad right before or at the time when my alternator decided to go.

But a little word of advice for anyone wanting to change spark plugs. My spark plugs came out easier then any car I've ever worked on and here is what I did.

Took the coil off. Engine was hot. Sprayed carburetor cleaner around the plug while the engine was hot. Came back 20 min. did it again ( its so hot at this point that it boils and dries off ). After first 60 min., I left a pool of carburetor cleaner ( small, but maybe covered a 1/3" of spark plug hole ) let the engine come down temperature wise ( still warm... these engines take For-ev-er to cool off ) For approx. 2 hours?. I then took a rag and wiped the cleaner out and to get it completely dry blew the rest of the cleaner out with compressed air. I then gave the spark plug a 1/4 to 1/2 turn, sprayed just a little bit ( i don't even think this step was necessary ). Let it sit for maybe 10 min and it came out easiest as pie.. almost to easy. It takes a while, but really worked. And my car had 100k with original plugs.

Thanks for all your help everyone.

05YellowGT

I've never had any problem with mine , but they've never had more than about 18k on them. If I'd had 100k on mine I would have been nervous as hell taking them out ...

karman

I never understood why they advised not to do it on a warm engine (hot I understood).
Seemed like it should be easier with it not totally cold.
Did you put the anti-seize on or not bother to?

Scrape

anti seize is a must for those engines. But be careful where you place it.

runfox

Thats what mine is doing after I took off the battery cable to clean it. Its idling 500 -700 rpm way too low. So I guess I need to diconnect and try your 60/40 deal..

Cavero

had the same warning for my 96 Monte. It was because of the aluminum engine block. Guess the metal gets really soft when warmed up

I guess there's also the potential that when you torque it down on a warm engine, the metal will contract when it cools and could cause damage