HELP!!!!

[ranger11x]

So starting last night my ecoboost AT (see sig for mods) started stuttering/fluctuating idle when comming to a stop, and today while driving i came to a stop at a stop light and it completely stalled out TWICE!! it's acting like there is a vacuum leak i checked all connections and they seem solid. Has anyone else had this issue before and what was done to fix it. please help guys this is my daily and i cannot be with out it long.

Sponsored

 

[TheLion]

So starting last night my ecoboost AT (see sig for mods) started stuttering/fluctuating idle when comming to a stop, and today while driving i came to a stop at a stop light and it completely stalled out TWICE!! it's acting like there is a vacuum leak i checked all connections and they seem solid. Has anyone else had this issue before and what was done to fix it. please help guys this is my daily and i cannot be with out it long.

Start with the obvious, check for codes, when I had a cracked plug insulator, there was no CEL (although I'm sure it would have eventually come on).

I had very rough idle, whole car was shaking and also very "knocky" sounding due to misfire on cylinder #4 that was occurring. Once I got home I read 0304 and 0316 despite no CEL...calm down and work the problem, it's easy to get "panicked" when your not expecting something to go wrong and it suddenly does without warning.

 

[ranger11x]

adam just suggested the same thanks alot man!!!

 

[ElAviator72]

Maybe get a borescope and check the carbon deposits on your intake valves? Severely coked intake valves will cause stumbly behavior, usually when cold, but if it's bad enough, can cause similar problems on a warm engine, too... :shrug:

P.S. If this is found to be the problem, do NOT put Seafoam or any other engine cleaner down the intake. You will destroy the turbo, and if Ford finds evidence that you used such a cleaner, you're SOL on your warranty. The solutions are 1) if still under warranty, Ford will replace your cylinder head (no joke!) or 2) walnut shell media blasting.

 

[TheLion]

Maybe get a borescope and check the carbon deposits on your intake valves? Severely coked intake valves will cause stumbly behavior, usually when cold, but if it's bad enough, can cause similar problems on a warm engine, too... :shrug:

P.S. If this is found to be the problem, do NOT put Seafoam or any other engine cleaner down the intake. You will destroy the turbo, and if Ford finds evidence that you used such a cleaner, you're SOL on your warranty. The solutions are 1) if still under warranty, Ford will replace your cylinder head (no joke!) or 2) walnut shell media blasting.

The walnut shell method is reported to be very effective. Subaru recomends that for WRX owners ever 40k (have a co-worker with a WRX and he told me about that).

A catch can, good oil and paper air filter will go a LONG way to keeping those intake valves clean however, but still might be worth it every 50k~60k even with those measures.

 

[ranger11x]

14k miles had a catch can since week one of ownership and clean the mmr cai air filter monthly and use amsoil for every oil change every 5k miles.
Just put fresh plugs in and still have the same problem although I did get a code p2195 o2 sensor bank 1 sensor 1 biased/stuck lean.

 

[ElAviator72]

The walnut shell method is reported to be very effective. Subaru recomends that for WRX owners ever 40k (have a co-worker with a WRX and he told me about that).

A catch can, good oil and paper air filter will go a LONG way to keeping those intake valves clean however, but still might be worth it every 50k~60k even with those measures.

Wow, is the WRX now a Direct Injection engine? Wasn't aware of that...;)

 

[TheLion]

Wow, is the WRX now a Direct Injection engine? Wasn't aware of that...;)

WRX is, not the STI. WRX is direct injection and twin scroll turbo as of 2015, same time Ford's first twin scroll was released (aka the 2.3L). STI is still pretty much the same as it was for 2014 which is why it's not any faster than the Focus RS but gets horrible fuel mileage (I think the V8 stang just about matches the WRX in fuel economy with 2x the cylinders...).

 

[ranger11x]

New info! It starts bouncing idle after warming up from a cold start.

 

[Witj85]

Vacuum leak? Had a Honda that did that

 

[paullyd210]

suggestion if after completing the above and problem persists.. check your entire exhaust system starting from where the downpipe meets the turbo, have someone turn on car keep in park and rev it while you check it out if there is a gap somewhere you will either hear it or see smoke come out of the exhaust leak area

 

[ranger11x]

So after checking everything the problem was still there so I revved it hard and now it ideling decent with a very occasional sputter

 

[ranger11x]

And spits a little bit coming down on the rpms

 

[TheLion]

And spits a little bit coming down on the rpms

If you have a stock DP, you should be able to go back to stock tune (realize your running the Mishimoto DP, but if you have the OE still you could swap it out). See if that resolves any of the issues. That's one reason I never upgraded the DP (well also Adam found it's almost a meaningless change on a stock turbo), for trouble shooting purposes the stock tune is pretty safe and a good fall back if need be.

No matter who writes the PCM software, some times the massive amount of testing and reliability built into the Ford OE software still trumps all else as it's a known good quantity to compare it in order to weed out hardware issues.

BTW, the idle on mine has always been a bit coarse when compared to my previous car, stock or LMS tunes makes no difference to the idle (BP fuel seems to be a bit smoother though).

 

[ranger11x]

Ok good news I think we solved the problem. The boomba check valve was leaking air! so I took it apart cleaned it and used some teflon tape on the threads of the check valve then retightened all of the clamps on each connection of the hose. It's now idling at about 700 rpm steady with 19.6-20 Hg or -9.65/-9.70 psi vac, afr is 13.9-14.1. Took it on a drive and sputtering is gone and no longer surges at a stop or idiling!

Sponsored