the infamous cobra idle stall.

[Sonic blue]

Hey guys, new to the forum. I just purchased my first 03 cobra, and it has the common "stall" while rolling in neutral up to a stop in cold weather. I read that i could relocate my Mass air meter to possibly cure this. I changed the plugs, cleaned maf, iacv, and air temp sensor this morning, but no difference. Car has stock upper intake tube but has a bolt on (inside fender) filter adapter. Any thoughts would be appreciated. Stock throttle body as well. 2.76 upper pulley, 4lb lower, i think (billetflow 4 piece set), o/r prochamber h-pipe, unknown dyno tune. Runs perfect otherwise.

 

[Jimmysidecarr]

Hey guys, new to the forum. I just purchased my first 03 cobra, and it has the common "stall" while rolling in neutral up to a stop in cold weather. I read that i could relocate my Mass air meter to possibly cure this. I changed the plugs, cleaned maf, iacv, and air temp sensor this morning, but no difference. Car has stock upper intake tube but has a bolt on (inside fender) filter adapter. Any thoughts would be appreciated. Stock throttle body as well. Unknown dyno tune with 2.76 upper pulley, 4in lower, full exhaust. Runs perfect otherwise.

Assuming no vacuum leaks anywhere and no bad parts an unknown dyno tune is reason enough to get the tune checked or replaced.

 

[Sonic blue]

No vacuum leaks, 25k miles. I'm pretty sure the car hasn't had the updated reflash recall done, and it does run slightly rich throughout the powerband so i know it's not leaning out. Will it hurt for me to get it reflashed and still drive it with the smaller pulley, or at least until i can return my mach 1 to stock and get my SCT x3 reset for the Cobra? I know these cars are sensitive to improper Air/fuel ratios. I have had the battery unhooked for 2 hours to perform the relearn process in a few minutes, just in case something was altered since it was unhooked last. Thanks for the reply. >No luck on ecm reset. doesnt matter how hot or cold the motor is, if its cold outside and i let the rpm's fall from at least 3k during a roll, the car stumbles at 500 rpm's, then dies. Vacuum stays at 20 pounds btw.<

 

[Sonic blue]

Perhaps, not everyone has googled this problem as much as i have. I wonder if installing the air filter back in the engine bay will keep the ambient air warm enough to prevent this from happening. Surely someone has had this happen a one time or another..

 

[dwish]

I had this happen pretty often when I briefly installed a K&N FIPK intake. Basically, if the car was moving and I was in neutral, it could stall.

I went to Ford and asked them for the update. They looked at me like, "really?"...but they did it, and told me my car did in fact have the outdated version before that. Never stalled again.

 

[T0RCH3D]

I had this happen pretty often when I briefly installed a K&N FIPK intake. Basically, if the car was moving and I was in neutral, it could stall.

I went to Ford and asked them for the update. They looked at me like, "really?"...but they did it, and told me my car did in fact have the outdated version before that. Never stalled again.

I noticed the same problem after I cleaned my K&N FIPK filter and re-installed. What 'update' is done my Ford.

 

[timspony]

First off, congrats on the new Cobra!

Its funny to be reading this...only because the last time I had my DSG Cobra out, this happened to me while rolling in neutral to a stop light! Now I blamed it on my 93 tune (I had been running E-85 since Spring), now you have me thinking! ...and I've owned this Cobra since 2005! This is the first time I can recall this happening...never on the 2004 TR RagTop though

FYI: My filter is in the engine bay....

 

[blwn89gt]

My 03 does this too occasionally. It does become quite annoying.

 

[cobracide]

First try and reset the computer, clean the maf to see if it helps. if not, it's probably in the tune. Get a new tune and shift faster in the meantime.

 

[Sagittaria]

Iac

 

[cobracide]

Iac

Possibly.. When does the stall occur? If you gun it and let the clutch in or it just won't idle?

 

[SilverNotch]

I had it in my 01 n/a cobra and everybody told me it was a iac and I changed it and it was alittle better but, not fixed. It eventually ended up being a bad canned tune. New tune no problem.

 

[blwn89gt]

I plan on having my 03 re tuned this upcoming spring. il just deal with it till then.

 

[racebronco2]

Hey guys, new to the forum. I just purchased my first 03 cobra, and it has the common "stall" while rolling in neutral up to a stop in cold weather. I read that i could relocate my Mass air meter to possibly cure this. I changed the plugs, cleaned maf, iacv, and air temp sensor this morning, but no difference. Car has stock upper intake tube but has a bolt on (inside fender) filter adapter. Any thoughts would be appreciated. Stock throttle body as well. 2.76 upper pulley, 4lb lower, i think (billetflow 4 piece set), o/r prochamber h-pipe, unknown dyno tune. Runs perfect otherwise.

Where is your maf located, in the fenderwell or the engine compartment?

The maf needs about 12" of straight airflow before the maf to get a good reading. If you can datalog the maf counts you can probably see they are all over the spectrum. On that other forum people have installed a screen before the maf which was reduced the maf count differences, it seems like the air it to turbulent for the maf to read it consistantly. Maf count before the screen varied in the 20-30 range and after the screen was in place it didn't vary more than 10 maf counts.

 

[Sonic blue]

Wow at the replies. As previously stated, all sensors have been checked and cleaned, no cel or stored codes. Car runs and pulls flawlessly. Drove it alot today in 70+ degree weather with no hiccups aside from the occasional fall to 600 rpms then back to 1000, back to 800. MAF sensor is in the oem location as its still installed in the factory upper intake tube. But there is an adapter for the inner fender style intake bolted to where the factory filter housing would be. If the outside temp is below 50-ish degrees (night-time) and i drop it in neutral to roll to a stop. It wants to stumble around 800, then to 500 rpm's before it just goes dead, UNLESS i downshift or tap the throttle a few times to let it regain ''normal" idle at 800. The bend in the tube is 90 degrees up to the maf sensor, from the fender..

 

[Sonic blue]

Its a full 4 second delay where the car doesn't know what to do when the throttle is falling during a neutral roll. i have to blip the throttle during that 4 second window to keep it awake before it remembers the proper idle when its cold out. The temp of the engine makes no difference in this, whatsoever.

 

[Sonic blue]

Racebronco2, what type of intake will allow me to run a 12'' tube "before'' the maf sensor?

 

[Sonic blue]

blwn89gt, i may just need to go ahead and recal. my ecu and start over to cure this. Its just annoying that i can't drive it during these cold nights without it doing this over and over..

 

[2004Droptop]

My MAF and filter are outside the engine compartment and never had the stall issue that you speak of. Possibly tune...

Since I put cams in I have stalled more than once taking off but I am pretty sure that is pure driver error forgetting about the cams and loss of lowe end tq

 

[Sonic blue]

What "screen'' do i use to place before the maf. I read where that works as well. Is it something i can make with store bought materials?