Napoleon85

I generally hate posts like this but I'm not entirely sure what else to do since I can't find anyone in the area with a lot of experience with the 4.0 Mustangs to help me diagnose a couple weird problems that I have been having. I apologize if any of these are posted elsewhere but I did try to search and didn't find any helpful information.

1. Sometimes when I start the car it immediately tries to stall. This issue has been very hard to nail down since I have tried switching between my 87 and 93 tunes, tried different brands of gasoline (Shell, BP, Marathon, and even Speedway) and just about everything else. It also does not seem to be related to the ambient temperature or whether I am parked on a flat surface, incline or decline.

2. Sometimes when I start the car and get moving the gas gauge drops to E and I get a low fuel warning. This generally rectifies itself as I drive and only seems to happen when I drive up an incline (not extreme enough that this should happen) immediately after starting the car.

3. When the car is idling I hear a metallic rattling from under the hood. I have visually inspected the engine while this is happening and have not been able to identify any specific cause. If anyone is interested I could upload a video of this.

4. When cruising around 40-50 mph I head a crazy sound that I can best describe as the CAI gurgling air. Is this normal? I have heard that it's typical of the drivetrain but it sounds terrifying and scares the **** out of my passengers if they haven't heard it before. Also, it is worth noting that if I turn off O/D I do not notice this but I suspect this is due to the engine running higher RPMs in that speed range since it's that gray area where O/D is just starting to do it's thing (from what I understand anyways).

My mod list is in my sig but here is some other usefull information:
-The odometer is sitting at 21600 right now
-I use Shell 93 octane gas almost exclusively
-Every oil change since 15k (when I bought it) has been Mobil 1 full synthetic

Any help on these problems will be greatly appreciated and if you happen to be in the Dayton/Cincinnati/Columbus area and would be willing to help me take a look at this I would be willing to compensate you with food and beer

Thanks in advance!

28HopUp

I'll take a stab at Item #3 -

The tensioners for the cam chains on the 4.0L can get noisy. Check to see if it sounds like it's coming from the valve covers (driver's side most likely). Pretty typical of a truck motor - you should be OK.

I would also recommend changing your fuel filter if you haven't done so already. I change mine once a year.

Napoleon85

I'll change the fuel filter this weekend (pretty easy to do and I just read the write-up on it yesterday). I'll try to find out exactly where the rattling is coming from. It doesn't sound too bad I just don't always recall it doing it (seemed to start right after I got out of my 3/36 of course).

Must8ng

Could it be the fuel pump? There was just a thread....ok here it is. https://mustangforums.com/forum/4-0l...left-turn.html The fact that it tries to stall, and the gas gauge goes to E makes me suspect. Good luck!

yellowneck86

It could be your tune. I had the same issue with the vmp tune where as my car will sound like it will try to stall out during warm startups. the gurgling noise you're hearing was explained to me by justin that it was the torque converter kicking in at 40 mph. I switched out to a dyno tune and never had an issue since.

07redMustang

I too am having the random stalls. I'm currently running a vmp 93 performance tune. I just purchased 2 tunes from Doug over at BamaChips.com and will let you know if it cures my problem.

I'm not having any of the other issues you've stated though.

07redMustang

I just installed my tunes from Doug 93 race and 93 torq and took my car out for a 30 min trip. I shut the car off for 5 min and started it back up and the car didn't even think about stalling. These two tunes are so much better then VMP and my car runs so much better.

illin

I have never owned a VMP tune, so I cannot compare...but when I loaded the 93 Race tune of his, my tune serach was OVER. It just flat rocks.

If the whole cast of the Victoria's Secret Runway Show decided to be your "gals"...would you really need to go bar hoppin' in search of love? Ummm...no.

OP, 100% sure you have a fuel pump issue. If the two fuel issues are happening at once, you could have some kind of weird power issue to the fuel pump. If the dealer wont touch it without "duplicating it" drive around with your digicam int he car...and when it pops up, video it happening. I have tried that twice now with oddball service/warranty issues and both were addressed right away with video proof.

locorider21

yea sounds like a fuel pump issue

Napoleon85

Yikes ... I was hoping this wasn't the fuel pump since I just dropped out of my 3/36 and it looks like the fuel pumps are around $200-275 just for the part. I have had this happen once or twice after driving but it sounds like it's the same issue described in the TSB (I found a copy in PDF format). Maybe I'll try printing the TSB and taking it down to the dealership to see if I can sweet-talk them into doing it.

Regarding the CAI/Tune issue ... should I flash it back to stock and leave the CAI on before I take it to the dealership? This will make it throw a CEL since the MAF is in a larger housing and I would hate them to just blame the issue on this but I would hate even more for them to flash my car. Would this lock me out of my xcal-3?