K8 turbo running but cutting out at 4500 rpm

K8Boosted · Post by **K8Boosted** » May 13th, 2007, 12:10 am

Hi i just joined the mx-3 forums this is my first post so sorry if there is anyproblems ive been working on my mx3 for 2.5 years now ANyways to the problem

I decided to attack the turbo idea i thought i better practice with the k8 so when that goes i can have a klze or de turbo
My setup
.57 trim turbo (EBAY)
the usual turbo pipes (puts turbo in stock airbox spot)
4 pound external wastegate witch has alot of chatter
Intercooler
Vortech FMU 12:1
Greddy BOV With the strong spring took out (Still doesnt open worried about that)
relocated cruise control
coolent check thing and resovoir relocated copper coolant lines thought would be smart to use by the turbo heat reasons)
Running vaf sensor then bov

Alright so the turbo setup is ready to go start revs in nuetral very smooth,wastegate chatters, great oil pressure, evering thing is perfect

Car sounds awesome drives good so after babying it for a couple miles i decide to rev it up first gear is good, shift to second get to 4500rpms and the engine stops push in clutch rpm goes down and drives normal

EVERY GEAR BUT FIRST CUTS OUT AT AROUND 4500 RPMS

correct me if i am wrong but due to the car not being under much load in first it prolly does not creat boost so thats why it works

So in second through fifth it creates boost and the car canot handle the 4 pounds of boost

So my idea is the car is either leaning out and could be fixed with a bigger fuel pump (But i think the 12: 1 fmu should handle that

Or the VRIS is affecting it
I KNOW NOTHING ABOUT VRIS I hear of tieing it open or somthing like that
PS I HAVE GUAGE SPONSERSHIP THROUGH CYBERDYNE BUT THE BOOST GAUGE I GOT THE SENDER IS BROKE SO I CANT READ BOOST PRESSURE I KNOW THAT WOULD BE USEFUL INFO BUT I HAVE TO WAIT FOR THE SENDING UNIT TO COME IN

THE TURBO BLOWS I TOOK I/C PIPING OFF AND FELT IT

If ANYONE HAS EXPERIENCED THIS PROBLEM OR KNOW SOMTHING ABOUT IT PLEASE HELP ASAP

Bochek · Post by **Bochek** » May 13th, 2007, 8:18 am

alright, what are you using to adjust for the extra air going into the engine? You could be leaning out so far that it just wont run.

Or you could be blowing out the spark, all tho i doubt that at low boost.

just some ideas, - Bochek

XxantwawnxX · Post by **XxantwawnxX** » May 13th, 2007, 10:56 pm

what are you using for fule/spark managment?

hgallegos915 · Post by **hgallegos915** » May 14th, 2007, 1:07 am

hmm that sounds like spark blow out..

K8Boosted · Post by **K8Boosted** » May 14th, 2007, 2:43 pm

Thanks for the quick reply i have stock gap and wires and running a 12:1 vortech fmu on a stock fuel pump

I will shorten up the spark plug gap to see how that afftects it
Do u guys have any recomendations on spark plugs and wires

I know i should have the walbro 255 lph fuel pump but i dont have the money or time to install it right now

andy · Post by **andy** » May 15th, 2007, 7:10 am

vris will have nothing to do with the cutting out.
The spark plug gap could very well be the culprit.
the more boost you have the smaller the gap.
gap them down to .030", should be plenty for 4psi.
I didn't see your complete setup anywhere.

Are you using the stock fuel injectors?
if not you could get a set of 220cc injectors from any 2.5l motor.
or the 280 cc injectors from the super charged version of the millenia.
You won't need a 255lph fuel pump until you up the boost.
and when you do, you will need a AFPR,(adjustable fuel pressure regulator). or the car will run very rich.

I'm not sure about running the vaf sensor then the BOV in that order.
I'm running the BOV then the vaf sensor and have never had a problem.
I would speculate that when the BOV opens it would mess with the VAF sensors air readings the way you have it and treat it like a vacumm leak.
Show us some pictures or EMail me some.

Andy P. 93 GS 1.8T

K8Boosted · Post by **K8Boosted** » May 15th, 2007, 9:47 pm

well tonight i went and got new plugs took old ones out and they were in perfect condition however they were gap at .50 so i got the new ones and gapped them to .30 took the mx out for a test and no change

By the way i am running the bov then vaf i said it backwards up top sorry about that

However today i was thinking about in chemistry class (as usual thinking about cars) my greddy bov has two spring inside which i took the storng spring out becuase it wasnt opening in nuetral so could it be when i actually create the 4 pounds of post the bov opens and leaks cuasing the car to stop then when i let off and the bov closes making the car kick back in

Going to but the spring back in and adjust it

Does anyone have any other simple suggestions before i tear into things

I have a car show the weekend of june 1 Drop Fest great show ALL IMPORTS, SLIDE SHOW, DRAGS, and a hot as hell bikini contest
If any1 is going tell me cuz last year not one MX3, Probe, MX-6 IT's really sad how people get so cought up in hondas and forget about everything else

XxantwawnxX · Post by **XxantwawnxX** » May 16th, 2007, 10:10 am

What injectors are you running? i hope not stock?? You need at least the 280's from the millinia.

K8Boosted · Post by **K8Boosted** » May 16th, 2007, 10:02 pm

yes i am running stock injectors would 220cc be alright cuz i can get those for almost nothing

I dont want to spend too much on this cuz i want to rebuild a kl this winter or sooner if this engine goes.

mr1in6billion · Post by **mr1in6billion** » May 17th, 2007, 1:05 am

I'm surprised the first few answers weren't "where's the fuel?"

You hadn't mentioned injectors until later (which should be upgraded) or fuel pump (which needs to be upgraded). And as far as I can see you have no way to tune it or see how it is running. How do expect to keep the car running without some form of afm or wideband?

XxantwawnxX · Post by **XxantwawnxX** » May 17th, 2007, 2:00 am

K8Boosted wrote:yes i am running stock injectors would 220cc be alright cuz i can get those for almost nothing

I dont want to spend too much on this cuz i want to rebuild a kl this winter or sooner if this engine goes.

Ur injectors are getting maxxed i bet, with the FMU. NO fuel for joo. Id do it right get some 280's. But 220's would be good for around 6 psi(more with a stand alone) i would assume. But i dont trust those FMU's.

andy · Post by **andy** » May 17th, 2007, 7:31 am

Yes get some 220's like someone said they should be good for at least the 4 psi your running.
Do you have a boost gauge? or air/fuel gauge ?

Is the cutting out only when the motor sees boost?
Try disconnecting the pipping just before the VAF. run the car up to redline. is it normal. without boost the car should run. You could start to narrow down the problem. At this point it could still be a mechanical problem or an electrical problem. verify that all your hoses are staying sealed under boost, especially the hoses inbetween the vaf and the TB.
Are you using the stock FPR?
check to make sure you have the fmu hooked up right.
this could even be a distributor about ready to take a dump.

Andy P 93 GS 1.8T

K8Boosted · Post by **K8Boosted** » May 17th, 2007, 10:23 am

yes i have tons of guages i have a sponsership though cyberdyne guages the air to fuel has a very slow response oil preesure fine i do not have a fuel pressure guage i asked them for one last night and my boost guage sending unit is not working corretly its ready 17 psi lol

andy · Post by **andy** » May 17th, 2007, 12:29 pm

My external wastegate was suppose to have a 4 psi spring in it when I ordered it. The reality was that I wound up with a 7psi spring.
You could have a different spring in there.
If your boost gauge is not working properly, maybe your actual psi's are
much higher than you think.
I have a narrow band A/F gauge. Its not completly useless but maybe a close second.

If you search you'll find My setup.
I ran 12-13 psi for 3 months during our S. florida winter But I'm back down to 10 psi for the summer months. I have well over 30k miles on this setup and over 185k miles on the engine. once you sort out this
cutting out you will be a happy camper.

Andy P. 93 GS 1.8T

K8Boosted · Post by **K8Boosted** » May 17th, 2007, 2:06 pm

I was actually thinking of that myself hey andy did u ever drag your car if so what was ur best time