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Fuel Cut/Bogging?

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Marceldsm

10+ Year Contributor
321
2
Jan 13, 2010
Montreal, QC_Canada
so i repair all the wiring and the ecu

and men the car started like a beast
no problems what so ever only problem the TPS IS MISS AJUSTED and im getting a random tps code from time to time

THE TING IS THE CAR WORKS GOOD THEN.......AT AROUD 4000 RPM IT JUST CUTS
FEELS LIKE FUEL CUT

IS IT A VACCUM LEAK
A MAF PROBLEM ( I HAVE A NOTHER TO TRAY )
A FUEL PROBLEM ( MY FUEL TANK ITS ALMOST ON EMPTY) CAN THAT BE THE PROBLEM

I CHANGED
FUEL FILTER
SPARK PLUGS
OIL
COLANT
TRANNY OIL

IL ADD SOME GAS ( THE CAR WHASENT RUNNNING FOR THE LAST 2 MONTHS THATS WHAY THE GAS IS LOW )
THE AIR FUEL IS RICH WHEN THE ENGINE IS COLD( NORMAL )
THEN AT NORMAL TEMP AROUND 12,5 OR 13 TO 1

CAR IS COMPLETY STOCK
ONLY A 2.5 " EXHAUST WHIT NO CAT
FRONT MOUNT INTERCOOLER



update

i found a missive boost leak at the blow off valve
its fix new

same ting again , and the idlle swhich came off new the car revs to 1800 and stais there
will fix that sonn


shod a ckeck for leaks again or get a new ecu and see what happens !!!!



the ting is the car new revs to 5000 before whit the boost leak it revd to 4000

any ideas !!!




update

fond 4 massive bost leaks 1 at intercooler pipeing a noter at the blow off valve 1 in the vaccum lines and 1 in isc fix all

the car runs better

after all that i install a new ECU


Same story again

no codes do

the stange ting is if the tps is at 5% at idllé im not getting any codes and the car cant past 4500 rpms
if i let the tps at 2% ( i cant find 0) it gives me a tps code .........and the car boost to 5500 then cuts power


at 4000 rpms my data logger tells me 45 nock
84% injector duty cycle at 86% throttle
normal o2 reading

the car just cuts power right there

whay i need help please

i know its not the ECU

I WILL TRAY A NOTHER MAS AIR FLOW SEE WHAT WILL HAPEND

I CANT BE THAT 3 ECUS HAVE THE SAME EXACT PROBLEM
 
So after trying to read all the information.

I still think you have a boost leak or air is leaking somewhere

How is your compression is shot. Do a compression check as well and see what you find.

Also is your car smoking at all? If it is, im guessing black, which would mean extra fuel.

Lastly a BAD o2 can make the car run a little ruff. So it could be a o2.

I highly doubt your ECU is messing up your fuel trims and it just so happens that 2 or 3 were bad.
 
So after trying to read all the information.

I still think you have a boost leak or air is leaking somewhere

How is your compression is shot. Do a compression check as well and see what you find.

Also is your car smoking at all? If it is, im guessing black, which would mean extra fuel.

Lastly a BAD o2 can make the car run a little ruff. So it could be a o2.

I highly doubt your ECU is messing up your fuel trims and it just so happens that 2 or 3 were bad.

compression whise

170 165 160 170 :thumb:
cand find other boost leaks i check and duble check

the car runs normal whance it reaches 4500 to 5000 its ok its just smokes black smoke only and if you FLOOR IT

after 3 ecu ...........they cant all have the same exact problem

i will test the o2

becose my data logger it says 0.38 v when the car is at 11.1 air fuel :confused: is that right ............sound whay off

at 11 im tinking at least .75 to .80 v no :confused:

It sounds like a boost leak still, take the intercooler off and test it to see if it's leaking.

i will soke it again with water and shope
the it is i fout up to new aroud 6 boost leaks


4 in the intercooler pipeing
1 at the isc looool :sneaky:

and o ya 1 in betwheen the turbo and the exhaust manifold l

1 in betwen the o2 housing and the exhaust manifold whic will explain whay the o2 gives me such stupid readings no :confused:
 
So your A/F ratio is way off, and you need to correct that, thats why. When the black smoke is hitting its ### your running really RICH so you are not getting enough air. You have a leak somewhere or something with your A/F is messed. Have you modded your A/F at all? All sensors are plugged in?

So im guessing you might have a bad O2, ### if it is bad, your car will bog and can run really rough and bad. And if you have a air leak there as well its gonna be worse.
 
So your A/F ratio is way off, and you need to correct that, thats why. When the black smoke is hitting its ### your running really RICH so you are not getting enough air. You have a leak somewhere or something with your A/F is messed. Have you modded your A/F at all? All sensors are plugged in?

So im guessing you might have a bad O2, ### if it is bad, your car will bog and can run really rough and bad. And if you have a air leak there as well its gonna be worse.

i just fix all the air leaks
i know there might m a very small leak at the 02 housing

at wot the car shoots black smoke the ting is the wideband gos LEAN

any explinations
 
is your greddy bov recirculated or open to atmosphere?

unless you have maf-t in blow-thru configuration(or another type of intake air sensor/controller), the bov WILL mess with your computer fuel trims big time.

factory computer does not understand blow off valves. that's why they factoy recirculates the blow off air charge.

you can MAKE a car run with a BOV, but don't expect it to run like a dream. if you get maf-t or something similar, you can blow off properly without affecting the computers readings.

try unplugging the BOV from the system, plug the vaccum line, and reset the computer. start it and see if it's any different.

just another suggestion.....
 
MAN your posts/descriptions are really hard to read. Check your o2 as stated, and sounds like you still have a boost leak coming from somewhere. Was it holding air just fine after fixing said leaks?

sorry doode me english is not the best
i will recheck for booost leaks around the intercooler

i will test the o2


any ideas or infos are welcomed


how do you test the fuel pressure on a dsm

is your greddy bov recirculated or open to atmosphere?

unless you have maf-t in blow-thru configuration(or another type of intake air sensor/controller), the bov WILL mess with your computer fuel trims big time.

factory computer does not understand blow off valves. that's why they factoy recirculates the blow off air charge.

you can MAKE a car run with a BOV, but don't expect it to run like a dream. if you get maf-t or something similar, you can blow off properly without affecting the computers readings.

try unplugging the BOV from the system, plug the vaccum line, and reset the computer. start it and see if it's any different.

just another suggestion.....

blow of valve is recirculated

so yor tinking that the type-s might have someting to do whit these
 
Ok let me just start by saying you need to go to english class or something. Secondly I cant believe no one has caught this. 45 DEGREES OF KNOCK!!!!! Holy shit! That is maxed out. Its not fuel cut at all, your timming is being pulled way back in the upper rpm range. Check the knock sensor and make sure its still good. I had this problem on my 1g and it would do the same thing I think your describing. Again though please use proper english, it will make your future post twenty times easier to understand.

Not only is it 45 degrees of knock but it is right at your problem area. Look at your timing at that same spot and see what you get. I'm guessing you have a logger and thats how your getting this info?
 
Ok let me just start by saying you need to go to english class or something. Secondly I cant believe no one has caught this. 45 DEGREES OF KNOCK!!!!! Holy shit! That is maxed out. Its not fuel cut at all, your timming is being pulled way back in the upper rpm range. Check the knock sensor and make sure its still good. I had this problem on my 1g and it would do the same thing I think your describing. Again though please use proper english, it will make your future post twenty times easier to understand.

Not only is it 45 degrees of knock but it is right at your problem area. Look at your timing at that same spot and see what you get. I'm guessing you have a logger and thats how your getting this info?

first off realy sorry abouth my bad English
yes i have a logger
i will redo the timing these week

is there a test i can do to see if the knock sensor works

tanks again
 
The easiest way to see if the knock sensor itself is bad is to get under the car and locate it and make sure there isnt a line of black tar/goo running down the back of your block. If you are under your car the knock sensor will be on the back side of the block twards the fire wall, will be to the left of the intake manifold support bracket. With that much knock im going to say its either unplugged, back sensor, or you have some serious issues or tons of phantom knock.
 
:confused:
The easiest way to see if the knock sensor itself is bad is to get under the car and locate it and make sure there isnt a line of black tar/goo running down the back of your block. If you are under your car the knock sensor will be on the back side of the block twards the fire wall, will be to the left of the intake manifold support bracket. With that much knock im going to say its either unplugged, back sensor, or you have some serious issues or tons of phantom knock.

can i plug my datalogger

and use a hammer mallet on the engine block see if the sensor works


i know it sounds stupid buth can i

you sayd on the intake manifold braket ........ok the ting is the old owner swap the engine so im figuring out the forgot someting

i will let you guys know
so this is the famous phantom knock :confused:
 
No dont hit the block with a hammer. The sensor can still be working just working inproperly. If that stuff has melted out of it it will pick up knock a lot easier and thats where you get phantom knock. And I didnt say it was on the bracket its to the left of it. Even if that bracket isnt there just go from the ac pump and go up the back of the block. Its the only sensor in that area. If its a 1g its like a 24mm so its fairly big in size. The 2g ones are 27mm. So either way it should stand out pretty easily.
 
update ................

someting very stange happend

i whas testing whi the dataloger
i whas driving my friend whas monitoring

so well yes the car hits the boogging problem at abouth 4000 rpm s

the ting is ..................... i give it around 75% throtlle and the car hit 5000 rpm cut then half a second later had full boost and whas pulling crazy............i meen no problem until like 6300 ( fuel cut)

so whay the hell for a spleet second the car dosent know what to do

data logger readings

o2 very s slowly
o2 whide band( data logger) stays constand
short fuel trim 98
medieum fuel trim 100
long fuel trim 1000

same ting knock at 4500 then no know at 5 to 6000 rpms then fuel cut

what the hell is going on

anybody !!! has idea !
 
Last edited:
Hello again .............i need your help again dsm tuners

so ya fix some massive boost leaks and decided to take the car for a speen

everytime the car whas dying and i tink i know whay the boost controler whas stuck at 22 psi on stock fuel system ............the spring inside bro

so i took the stupid ebay chinese pease of crap and trow it in the garbage

new the car is at 9psi everiting works fine again until i heat 5000 rpm it cuts expecialy in first gear

i had a check engine for coolant temp sensor

replacet it
change de ecu 2 times ( same exact ting )

new knock sensor work fine its not disconected nor broken nor leaking

im realy tinking 02 by know

my car is completly stock right new and im recirculaiting

the fuel trims stay constanly at 100% no variation what so ever

no check engine

maf works
all sensor work

the only ting im seeing on my data logger that looks suspecios is the 02 or better yet o2 wideband signal constanly rich ....................whay

and whay is the car still booging at 5500

do i still have a boost leak or someting
 
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