car falls flat on its face at full boost
 

I just upgraded to a 16g from a 14b with blown seals. Now, every time I hit full boost and keep it there, the car falls on its face as if I had slammed on the breaks. I was slightly concerned about my welding on the BOV flange. Could it be a leak that's causing this? The car is fine while building boost, it only fucks up under full boost. Could it be that I'm maxing out my stock fuel pump? Spool time is also a lot more with the new turbo as opposed to the old one. I thought the 16Gs and 14bs were so similar that fuel consumption/spool time wouldn't be effected this much. Any help or insight would be appreciated.

Re: car falls flat on its face at full boost
 

did you have a wideband on it, or are you just winging it? Did you even change anything with this tune?

And a leak at the bov would be pretty evident as your boost gage would fall flat on it's face with the car. aside from the fact that leaks are usually continuous not just at full boost, so spool time would blow.

Re: car falls flat on its face at full boost
 

16g's and 14b's want very different things from your engine. You didnt retune it did you?

Make sure the compressor housing has its o-ring. If yours is a ching chong meow version, it might have been forgotten. Find your boost leak and get it retuned.

Re: car falls flat on its face at full boost
 

So you think it is a boost leak?



Also, yeah, I didn't get the car retuned. I figured the turbos were similar enough to where I could drive it around until I got the chance to retune it. I just wanted to test it a few times to make sure everything was working the way it should be before I drove 3+ hours to get it retuned.

Re: car falls flat on its face at full boost
 

How about telling us what kind of car and setup, before asking for help...

Re: car falls flat on its face at full boost
 

Also check your plug gap.

Re: car falls flat on its face at full boost
 

Car's a 2000 Ford Focus non-SVT. 42 lb/hr injectors, stock fuel pump (might needed upgraded, not sure), 2.5" charge piping, 2.5" exhaust. Plug gap is .028 where it should be.

Re: car falls flat on its face at full boost
 

What is full boost?

I'd upgrade the wire to the pump, it's probably got 50-100 whp caught up in the stock wiring's failure.

Re: car falls flat on its face at full boost
 

Full boost is around 10 psi.

Re: car falls flat on its face at full boost
 

when it was tuned was boost cut set? if so then you could be hitting it

Re: car falls flat on its face at full boost
 

also what kind of wastegate setup are you running? if it is internal then it may have a different setting then the 14b

Re: car falls flat on its face at full boost
 

I don't think the tuner set a boost cut or whatever because the 14b wasn't spooling as fast as it should have (bad wg placement). I fixed the wg placement on this new turbo and I believe now that it's spooling when it should be given that I have a sort of bottle neck with my short section of 1.75" j-pipe. I'm hoping the problem is in the tune cause I'm getting it retuned hopefully next Saturday.

Re: car falls flat on its face at full boost
 

wastegate placement on spooling is a joke. wastegates dont open until you spool :1

Re: car falls flat on its face at full boost
 

boost cut is a saftey setting that is set a little higher then your desired high boost level so that if your wastegate doesnt open for some reason then it will shut your ecu down to protect your engine. when i had a shitty boost controller it would spike up and hit boost cut on my car some times because it was not allowing my wastegate to open at the correct time. btw when this happened it was so fast that my boost guage was chowing me 10 psi and my boost cut wasnt set to kick in till 14 psi so basically my map sensor was getting the reading much faster then my guage and cutting my ecu out. double check with your tuner for sure because when the ecu cuts out its like a sudden loss of all power then as soon as u let off of it everything is back to normal again untill you hit boost cut again.

Re: car falls flat on its face at full boost
 

isn't a 2000 focus returnless fuel system?

Re: car falls flat on its face at full boost
 

Good point. ----, I've had so many little problems with this car that have kept it running exactly how it should be/how I want it to that I can't keep track of what I did to correct what.

Re: car falls flat on its face at full boost
 

I think it is, yeah.

Re: car falls flat on its face at full boost
 

Bringing this back to try to get some answers. I got retuned today and it still died, but this time we figured out it wasn't a "once it hits full boost it dies" thing. It died every time at 5,000 rpms. The turbo spooled up from 3-3.5K rpms to full boost at 7psi around 4-4.5K rpms, and then it acted as if I hit the governor at 5K rpms. I just had a higher capacity fuel pump put in, AFRs and timing are exactly where they should be. What do you guys think the problem could be?

Re: car falls flat on its face at full boost
 

Sensor ground, or ignitor.

Re: car falls flat on its face at full boost
 

Could you be more specific? lol

Also, I just did another test run, and I could take it up past 6K rpms at full boost in 2nd gear, but 3rd and 4th died out around 5K rpms just like before.

Re: car falls flat on its face at full boost
 

There is only one sensor ground and ignitor.

Add boost cut to the top of your list.

Re: car falls flat on its face at full boost
 

kinda sounds like boost cut to me too since its higher rpm in lower gears. also try gapping your plugs down more. my car had a problem kinda like that on the dyno. the plugs were at .025". i put them at .018" and the problem went away

Re: car falls flat on its face at full boost
 

I changed plugs to a spare set of the same type that I had and the gap between plug sets changed from .028 to .025, and now it dies at 5.5K rpms in 2nd and 5K rpms in 3rd and 4th still.

Re: car falls flat on its face at full boost
 

Re: car falls flat on its face at full boost
 

Finish the rest of the tuneup. Cheap cap/rotor gets you by, but you HAVE to use OEM aka NGK plug wires. Don't worry, they are only $35-50 depending on where you go and don't suck ---- like the MSD/etc wires for twice the price.

Re: car falls flat on its face at full boost
 

Good ---- complex. That's hilarious

Re: car falls flat on its face at full boost
 

i just can't ------- comprehend how he is told what to do, and he does everything but


THEN he complainds what he did, didnt work. and the answer is right in front of him.

i see your solution, and raise you..

Attachment 9291
one amish buggy that i passed today

Re: car falls flat on its face at full boost
 

Herpes JB WELD boost gauge pod ftw

Re: car falls flat on its face at full boost
 

it's oil temp not boost. boost is on the column

http://img.photobucket.com/albums/v3...IMG_0128-1.jpg
you can see it hiding behind the steering wheel

Re: car falls flat on its face at full boost
 

someone explain to this complex faggot that I don't have a Honda, and most boosted foci run a .025-.035 gap. going from a .028 to .025 made things worse, so why would i drop even lower to .018?

Re: car falls flat on its face at full boost
 

Indeed. And eShaw, just leave HMT now. It'd be best.

Re: car falls flat on its face at full boost
 

suck my dick, this place is too good to leave.

Re: car falls flat on its face at full boost
 

Then take people's advice and at some point you can contribute info to others. :6

Re: car falls flat on its face at full boost
 

uhh... did you not read my post about not wanting to lower my spark plug gap to .018 because it's probably too low?

Re: car falls flat on its face at full boost
 

If you know more than the combined uncontrollable knowledgabilities contained within HMT, then why the ---- are you here asking questions. ------- hell. I will cut your head off and ---- down your throat

Re: car falls flat on its face at full boost
 

i dont know if you already said this or not cuz i try to just skim the post.. but does it sound like a miss when it falls on its face or is it just flat out going into a limp mode and shutting fuel off?? before my honda i had a v dub and every 4 months i would pretty much bake my upstream 02 sensor because i was running to high of boost and didnt have a good fuel system 24 lbs with stock fuel system and my 02 sensor would fry every 4 months and when it did everytime i would hit full boost under a heavy load-- like you said 3rd and 4th gear at full boost-- it would sound like a bad miss and kinda backfire like fuel cut.. sounded cool as ---- but it would only let me drive normal til i got a new one.
just maybe one more thing to check.
but then again my v dub was smarter than the average tuner so you couldnt ------- bypass ---- like you can on most cars or it would go into limp dick mode and only run 6 psi til you fixed it

just my .02 maybe another place for you to look i dont know much about a focus wit boost

Re: car falls flat on its face at full boost
 

What did you use to tune the car? On factory ford management useing like sct of diablosport there is no boost cut in the pcm. You can kinda build in a boost cut by takeing the cell in the maf transfer funstion that is the highest you get to and then make the next higher one a lowwer value, the pcm goes stupid and shuts off the fuel. But that not the way to do it right. In reality, there really isn't a good boost cut system in the factory ecu as it never was built in. There is a rev limiter obviuosly. If your useing sct or diablo, make a log of the run and post it and we can help you. Who tuned it last? Ask them if you can get the actual cal file from them. That would help too.

Re: car falls flat on its face at full boost
 

Why don't you try running a .018 gap first and then see what the results are. If it goes worse then put the gap back to where it works better.
Like JD said, It looks like you have an exposed spark plug wires or the wires are worn out. Had it happen on a honda once before with my 15 year old spark plug wires, put some other stock wires on and everything was fine.

Re: car falls flat on its face at full boost
 

most boosted hondas run .025" gap too. mine doesnt though. it likes .018"

plug gap doesnt care what brand of car you have, but more on the conditions inside the cylinder.

try a step colder on your plugs too.

Re: car falls flat on its face at full boost
 

simmer down there chief. pay attention to what i post. i basically stated that fords and hondas are two completely different machines and that what works for a honda might not be safe/work for a ford. my tuner, who basically wrote the book on tuning foci, said not to go below .025. so i will not go to .018 no matter how many honda owners think they know whats best for my ford.