So my 2015 SHO feels like it has a small misfire at idle on cold starts. It only lasts for about 30 seconds or untill the high idle settles down. Feels like rough idle, you can see the tach jumping 100 or so rpm's.
Anyone else have this?
Plugs are new and gapped .030. Its done it since i got it at 27k miles and now has 30.5k.
Im almost thinking it is just idling rough untill the turbos get spooled and moving proper air to idle right but idk.
Check for any loose hose clamps from top to bottom.
Ford Mode 6 Data would be Ideal.....
Check your Vapor purge valve solenoid. Z
https://www.ecoboostperformanceforum.com/index.php/topic,7133.msg137949/topicseen.html#new (https://www.ecoboostperformanceforum.com/index.php/topic,7133.msg137949/topicseen.html#new)
My PI and now my new SHO do the same thing. Only reason I noticed mine though was because I have full cat-less exhaust on both cars and I could hear it. I changed some parts on the PI to try to fix that and other issues and never could get the high idle thing to go away. I'm not that worried about it anymore since my new car does the same thing.
I found out overtime that the GTDI engines are quite stubborn on the quality of Fuel that goes in.....
To the OP do you have access to 93 octane fuel! I would also make certain to put in Top Tier Gas such as Shell or Chevron 93 octane fuel @ preferably a high busy turnover fuel station. Z
Thx guys.
Ill check all the clamps i can find on my next day off.
I use 89 from the same station always, it is the busiest station in my area. I ran one tank of 93 just to check milage and i get better milage with 89, ill try 93 again and see what happens with the idle.
Funny side note. The dealer was only getting 17.5 mpg on regular (salseman had been driving it). First tank of 89 the milage went to 23.5, now after 3k miles on 89 its getting a hair over 24 mpg.
I don't think it has anything to do with your fuel.
All 3 of mine exhibit/ed that behavior but there was never an actual misfire.
I've ran every fuel/E85 mix one could think of and it never changed across three different vehicles.
No idea what causes it but I really don't think its anything to worry about.
I have it on my '13 SHO as well. I have not watched the tach when it is happening, but it is clearly audible on cold start for a min or so.
I wouldn't worry too much....I think it's fords idle strategy ...it kind of regulates the torque of idle and idle speed with spark. Also I think fueling and combustion can be finicky until warmed because of fuel sticking to the walls
Also your wild swings in fuel economy are due to the testing. There is no way it can swing that much from octane.
If anything the higher octane will get ever so slightly more economy due to the car making a bit more part throttle power because of higher spark allowed ...if you make more part throttle power you will use less pedal to get up to speed which will use less fuel
From day one I had the same issue on my 2015 SHO ..chkd clamps they were fine...did it the entire time I had it. I always use top tier 91 or 93 octane juice. My 2018 SHO does not have this issue. Odd.
Im glad to hear im not the only one with this odd miss. Now im not worried about it but i am going to attempt to chase it down, because im an idiot like that. Lol
Im pretty sure my mech's scan tool is updated to the hilt so if all else fails ill see of he can pull the mode 6 data ( as ZSHO suggested) and then go from there.
Last time it was in the stealer for a warranty issue (brake rotors where pooched bad when i bought it and coolant was low) i told the desk lady about the idle. For some reason she wrote it down as a cold acceleration miss tho so no idle testing was done.
Good luck on chasing it down. I changed the fuel injectors, coils, plugs, pcv oil separator and valve, O2 sensors and installed new hot pipes on my PI to fix other issues and the high idle thing persisted through all of it.
FWIW try to fix any ongoing issues before the Factory 3YR/36,000 warranty expires,since your @ 30.5K IIRC! Best of luck. Z
I am able to view mode 6, never showed any issue.
Through the 3 cars I've only seen one Misfire ever.
There is a ton of emissions stuff going on during cold start and I would suspect that is the culprit.
Closed loop after 30 seconds!
My car was doing the same thing until I put 1 stage cooler plugs gapped at 0.028 in it. Idles like a brand new car now xD no more super low rpm misfiring. Try these brisk plugs pregapped to 0.028 imo their the best plug for our application unless anyone else knows of better plugs always like suggestions!
https://www.briskracing.com/brisk-spark-plugs/brisk-silver-spark-plugs/brisk-silver-racing-rr14s-spark-plug-detail
Sent from my SM-N950U using Tapatalk
And my SHO saga continues.
Brakes acting ike worse than not having power brakes and the abs seems to be dragging. Almost no stopping power at all and with the brakes dragging. Really odd.
Almost rear ended a tractor, had to get a tow. Flat bed luckily.
It could be the brake booster line check valve! Who changed the spark plugs!
There is a vacuum line near the rear spark plugs on bank 2!
I hope they get it fixed Pronto! Please keep us updated. Z
Highlighted in Red below!
(https://i.imgur.com/Se5tibXh.jpg)
I had my normal mech change the plugs who has done a lot of work on other vehicles for me with zero issues. I trust him 100%.
Is that booster line close to that driver side rear plug?
Id be very suprised if he f'd it up. Ive put 500+ miles on since he changed the plugs with no problems untill this morning.
Edit = your pic just now showed up for me. I guess that line could have gotten knocked around.
Its at the stealer now so ill update when i find out wtf is going on.
Edit 2= if the brake booster had a leak the brakes wouldnt drag though right? Just loose power?
Quote from: DstryEvrytng on June 01, 2018, 11:12:16 AM
I had my normal mech change the plugs who has done a lot of work on other vehicles for me with zero issues. I trust him 100%.
Is that booster line close to that driver side rear plug?
Id be very suprised if he f'd it up. Ive put 500+ miles on since he changed the plugs with no problems untill this morning.
Edit = your pic just now showed up for me. I guess that line could have gotten knocked around.
Its at the stealer now so ill update when i find out wtf is going on.
Edit 2= if the brake booster had a leak the brakes wouldnt drag though right? Just loose power?
It would feel like metal to metal contact depending how severe ! Z
It did kinda feel and act like there was no pad left on all corners. Shyt, time to go talk to my mech i guess.
It also felt like they where dragging. And after maybe 5-10 minutes of me calling the wife and stuff i felt the rotors and the fronts i could only touch for a cpl seconds. In my hot o meter thats way too hot (for the circumstance and braking i did to get the car off the road). the rears where also really hot/ way hotter than i think they should be unless dragging.
The first dash lamp that lit was the ABS. I didnt look again untill it was safe to do so and by then the big red "fix the brakes now" message was lit.
Quote from: DstryEvrytng on June 01, 2018, 11:42:00 AM
It did kinda feel and act like there was no pad left on all corners. Shyt, time to go talk to my mech i guess.
It also felt like they where dragging. And after maybe 5-10 minutes of me calling the wife and stuff i felt the rotors and the fronts i could only touch for a cpl seconds. In my hot o meter thats way too hot (for the circumstance and braking i did to get the car off the road). the rears where also really hot/ way hotter than i think they should be unless dragging.
The first dash lamp that lit was the ABS. I didnt look again untill it was safe to do so and by then the big red "fix the brakes now" message was lit.
The main issue is thankfully no one was injured during this ordeal!!!
I wonder if the Hose connectors were properly secured into the manifold!! Z
Thankfully i was behind a very slow moving tractor so if worse came to worse (it almost did) the only one hurt would have been the front of the SHO. Probly the intercooler and rad since the tractor was towing a menacing looking 1.5 lane wide land ripper. Lol. Another 5 mph or another car length closer and the car would need a nose job.
I am also wondering that. If the mech removed that line (idk why he would have) when changing the plugs then it makes sense. I do drive a five mile stretch of really rough pavement twice a day so if something was loose there is a bery good chance the road finished it off.
I appreciate the concern of no one being hurt btw. Man id be not happy if i was driving like an a$$ and rear ended someone with a kid in the car.
Also. Your engine top is about as pretty as i imagine a sho's could be. A polished intake manifold is the only thing i think that could make it any better.
Quote from: ZSHO on June 01, 2018, 10:47:58 AM
It could be the brake booster line check valve! Who changed the spark plugs!
There is a vacuum line near the rear spark plugs on bank 2!
I hope they get it fixed Pronto! Please keep us updated. Z
Highlighted in Red below!
(https://i.imgur.com/Se5tibXh.jpg)
Dealer just called and you nailed it. Brake booster vaccuum leak. The desk lady couldnt specify where the leak was but thats not really a question anymore at this point.
Now i will talk to my mech soon and explain the problem i had and ask if he removed that line when changing the plugs. Then etc... ugh
Thanks Z
If i had to fix it myself it would have been done roadside after a cpl posts here!
Its my pleasure DstryEvrytng! :) I was curious if the Ford dealer was able to check out the misfire,rough idle issue! Z
Now that its in the sixty degree temps ar night it has been cold idleing fine. Of course it idles fine while its at the dealer. Lol.
They are just keeping the car because it was going in on monday to replace those seals anyways. Im stuck with an n/a escape. Man ii thought the ecoboost escapes are slow, this thing barely moves. Haha
As far as the miss goes i think this guy may be onto something.
https://m.youtube.com/watch?v=baWZjtb3QlY&start_radio=1&list=RDbaWZjtb3QlY
In the diesel world (my old realm) fords ccv system caused all sorts of problems. Basically the vented air/oil mix was clogging up cold air charge pipes. So guys vented to atmosphere which in turn wouldnt vent enough because of no pressure from boost/ too long to elaborate much on that.
I never had idle problems (beside injector stiction, damn heui system) with the 6leaker. These dirty maps in the 3.5 tho could most deff cause air fuel problems imo.
Now i just need to find the maps on the transverse mounted beast to see if they are all oily.
One is on top of the intake manifold smack dab in the middle, the other is mounted vertically on the side of the throttle body/cac outlet pipe. Might as well clean the iat sensor too, mounted at the airbox.
You likely have a sensor on the cleanside pcv line, idk if it can be cleaned, but worth a look.
Quote from: DstryEvrytng on June 03, 2018, 11:12:54 AM
These dirty maps in the 3.5 tho could most deff cause air fuel problems imo.
Mine has done it and cleaning the MAPs seems to help the most. The one on top of the intake will end up looking dirty while the one by the throttle body not so much. Doesn't hurt to clean both and the IAT as SHOdded mentioned as well. They are easy enough o get too.
Got the car back today. After 7 days in the shop.
They said the ptu leak was from an "rf axle seal" and suposedly replaced. To me that means right front axle seal but the ptu was leaking from the rear output. Idk, i havent been under this thing ywt but im going to need too asap.
The brake booster leak was due to the vent tube at the intake coming off. As that is an stc fitting ill hafta blame that on my mech that changed the plugs.
New thing now though. I started cleaning the sensors to chase down the missfire, which it still has just not as noticable due to warmer weather. And found this T20 screw missing and obviously the shaft was broken off and the hole filled, milled and just left like that.
Wtf?? Im about to sperg out on the dealer.
Edit= Cleaning the pictured sensor on top of the intake and the big one on the cac tube did fix the missfire. So thats a win.
Ford has been using a single screw to hold the MAP sensor onto the intake for many a MY now. I think as far back as 2011? Perfectly normal.
Cheap fix for the misfire is a big WIN :D as is the BB leak fix.
Hope the rear output seal is not leaking! Clean up with brake cleaner and see if it reappears.
Glad to hear the single screw is normal. Weird that the mounting surface on the intake looks like the other hole was filled and sanded recently.
Yes by the end of the evening everything compiled to a win. Especially when my son ran out and realised his "fast car" was back. Lol
I forgot to mention the dealer topped off the ptu. I had asked them to change the oil but they said "we just topped it off with a quart because its a lifetime fluid". Lol. Wtf.
I asked "if its a lifetime fluid then where did the quart it was missing go". No logical answer to that one lol
Quote from: DstryEvrytng on June 08, 2018, 09:46:56 PM
Got the car back today. After 7 days in the shop.
They said the ptu leak was from an "rf axle seal" and suposedly replaced. To me that means right front axle seal but the ptu was leaking from the rear output. Idk, i havent been under this thing ywt but im going to need too asap.
The brake booster leak was due to the vent tube at the intake coming off. As that is an stc fitting ill hafta blame that on my mech that changed the plugs.
New thing now though. I started cleaning the sensors to chase down the missfire, which it still has just not as noticable due to warmer weather. And found this T20 screw missing and obviously the shaft was broken off and the hole filled, milled and just left like that.
Wtf?? Im about to sperg out on the dealer.
Edit= Cleaning the pictured sensor on top of the intake and the big one on the cac tube did fix the missfire. So thats a win.
Its kind of stange that the intake manifold does appear to be shaved down IMO!!!! GLAD to see the excitement with your son and all which brings back fond memories! Enjoy. Z :)
topped it off ... LOL LOL LOL
yes kids do seem to get permagrins too!