I'm going to be taking mine back to stock for a few days to see what happens. It could be that the car decided to behave itself for the few minutes I tried running stock two nights ago. I really did not give it much of a chance as it's so horrible to drive that way!

Tim

 

I'm going to need to. But the WMS is such a PITA to take off and return to stock. Do you have any links to what you read regarding this? I'd like to read up on it too... thanks.

 

You're welcome.
One of the following links mentions the air turbulence, and the other mentions making sure the the MAF sensor's wiring splices are secure.
http://www.mustangforums.com/m_42241...tm.htm#4224137
http://www.mustangforums.com/m_4362803/tm.htm

 

05GT-O.C.D,

Over on another forum Sky was kind enough to reply to my post about my troubles, and he made a suggestion I had not thought of. Here’s the conversation, maybe there is something to glean from it.
Thanks for the thoughtful tip Sky. I checked the MAF and the small rubber gasket is in fact in place. I never even realized it was there, I imagine that little gasket could cause quite a stir if it got lost though! You did get me thinking about other possible air leaks, and there is an area where two pieces of my CAI come together which may have been leaking some air. I went ahead and placed a small amount of silicone around the joint to ensure the connection is in fact airtight.

I also cleaned my air filter, which I had neglected to do so far. The reason being the filter company recommends cleaning at 50K, and the factory recommends replacement at 30K. My car has 14K and I figured it was fine, but I do live in a dry dusty area with lots of construction so maybe it’s a contributing factor.

I’m waiting for my filter to dry now before I oil it. In the meantime the stock air box and tune have the car running perfectly. I think it’s been narrowed down to the CAI or Filter, unless the problem simply does not manifest itself on the factory tune because it’s not quite as sensitive. That would stink! I’ll give the factory setup at least another day of driving before switching back to my newly sealed CAI and filter to see if it’s still happening.

I sure hope this fixes it, or I’m really going to be at a loss. I did email Doug about my problem and he was kind enough to offer his assistance. Hopefully I won’t need to bother him though!

Tim

 

Stock runs fine hugh? Great. All indications at this point are pointing towards my CAI as well.

 

Let me relay something that happened to me and many others. I too had falling RPM issues when letting off the gas pedal ,even to the point of stalling. Usually worse when cold. I was fouling some plugs. I took the TB off to clean trying to fix the problem. I looked inside the plenum and saw alot of excess oil dripping down the sides. The PCV system just alows too much oil blow-by as it recycles crankcase gases. This is pretty common I'm finding out. Its worse with higher modified motors. What I did is replace a couple plugs and put a oil / air separator inline to catch the excess oil before it goes back through the plenum. Problem solved. Runs like a champ again. Just empty the catch can periodically as needed. You should be able to find some other articles about this mod. Correction made on hoses pictured. Hoses were switched after this pic to proper placement. Plenum hose goes to bottom fitting under the can. This is a Moroso oil separator.
Hope this helps. Good luck !

 

"Fine" as in there are no technical issues, but boy does it suck!

Tim

 

Thanks Larry, I might give that a shot. I know people have done that, but it's the first I've heard of it solving the stalling problem.

On another note - it's not the MAF gasket. I checked my stock box, it's not there, so its on the CAI. After looking I specifically remember double checking it when I did the install.

I wish it was warmer... it sounds like I've got some projects to do.

 

Yea it was frustrating. I cleaned the MAF sensor ,TB to no avail. I had a couple of fouled plugs because of the excess oil issue. Also make sure your COP boots are connected well and not arching in the plug shaft. I also had 2 discolored boots,which told me spark was jumping around thru the boot. It was easy to see because I have Granatelli COP's and the boots are red. I put die-electric grease on the connectors and snapped them all back on.

 

You shouldn't have to take the wms intake off for any reason. It's probably something with the maf sensor. I've had the wms with 80mm MAF intake and no tune, and 95mm MAF intake with two different tunes and haven't had the slightest problem. I also have a hood with a gigantic hood scoop so if there would be some kind of turbulance issues i should get it.

 

I need to take the WMS off to put back to stock - that way I can either eliminate the intake as the source of the problem, or verify that it is. I've really checked everything... too long of a list. The problem didn't start until after the CAI was on, and has persisted ever since. Sure, it could be coincidence, but I've troubleshot most everything else. I've been putting it off because I didn't want to go through the hassle w/ the rad hoses. Why did you have both WMS'? What did you do with your 80mm?

 

Did you check that your MAF sensor's wiring splices are secure, as suggested in one of the links in my previous post?

 

Yeah, I just tug checked them. I also checked w/ Brenspeed and WMS - if there was an additional problem it would throw a CEL, and it's not. I'm still going to check them again when I return to stock... once the temp gets above freezing.

 

D A M N John - I hope you get that straightened out, brutha!

 

Have you seen this: http://forums.bradbarnett.net/showthread.php?t=73467

"Since I'm running the WMS, the MAF Sensor is only 6" away from the throttle body plates. The GT develops a lot of vacuum on deceleration. When the TB plates close there is a air backwash that develops causing the intake air to flow back toward the MAF Sensor. (wrong direction and clearly visible on the datalog)

Doug has been tuning all of that out. Plus the STFT's ( idle and cruise speeds) were not at exactly 14.7:1 (1.0) so those were also corrected where needed.

I dont really have anywhere to datalog WOT around here, so I'll have to wait until the dragstrip opens this coming spring."

Tim

 

That actually makes a ton of sense. Thanks!

 

I have been trying to pay more attention to the things it is doing when driving around the past few weeks. Some days it’s better than others, but generally the car continues to have idle surging issues.

It’s most noticeable when the car is “coasting” down the road at over 40 mph, the idle drops as far down as 400-500 RPM, then it surges back up to as much as 1500 RPM and then bounces around in between a few times. I think it can also be felt somewhat when in gear and cruising at lower RPM's such as under 2000 RPM especially in OD. The car does not stall, and it has not thrown any codes either.

I have tried all I can think to try. I have cleaned both the throttle body and MAF, reloaded my tune, cleaned the air filter and reset my computer to allow the car to re-learn the idle strategy. I got so frustrated I even went down to Ford this afternoon and purchased a new TPS which did not help at all.

For the time being I am running the car stock and have not had any problems (I have to give it a few days to be sure). Any advice/tips/help you can offer would be very much appreciated!

Tim

 

Are you running Bamachips' tune for the WMS that's supposed to solve this problem?

 

I'm not running the WMS, I have a Demolet. I'm not trying to hijack your thread, but our problems see to be so similar I'm wondering if there is not a common cause?

At this stage, I'm thinking it might be my CAI as you do. It runs fine stock, and problems exibit themseves on two different tuner's tunes. I have emailed both shops (purchased from one, later had dyno-tune from the other) to see if they can't help.

I'm going to leave it stock until I get some momentum on a fix, I don't want to risk damaging anything while I wait.

Tim

 

Yeah, it sounds like the same problem. I'm going to get the Bama tune in the spring when I take the car out again. If it fixes the problem as it's supposed to do, then I'll let you know. You could ask Doug if you could run it w/ your setup or if he'd need to tweak it first. We'll see, Spring can't get here fast enough. Brrr.