weird fuel cut problem? and weird noise?

[eclipertnr90]

I am new to the DSM world! and ive been having this problem for a while now! I have a 1997 Eclipse Gst and it has a 14b turbo racing dejon front mount, turbo back exhaust, stock injectors, stock fuel pump... I am running about 12-13 psi... and when its in the high RPMs it hits fuel cut?.. also when you step on it it makes this weird noise some said its "like a bov for the waste gate" i dont know if this is true but it sounds pretty bad it doesnt sound right? does anyone have any idea what this could be?

 

[nightracer91]

Could you make a quick video for better diagnosis of the noise? Fuel cut is all based on Injector Duty Cycle. So when your Duty Cycle hits 100%, the ECU shuts the fuel system down to save it from leaning out and blowing up. If you are running really rich, 13psi could be enough to max out those 450cc injectors. Have you checked your O2 sensor, if that is faulty or has a slow response, that can cause weird fuel issues.

 

[rush2252]

check fuel pressure. Try changing your filter first. This could also be due to low fuel pressure. The stock ECU should maintain fuel trim to 16psi on that car.

 

[nightracer91]

check fuel pressure. Try changing your filter first. This could also be due to low fuel pressure. The stock ECU should maintain fuel trim to 16psi on that car.

How would low fuel pressure cause fuel cut at a lower boost level than a "good running" car which cuts at 17psi.

 

[U2_slow]

I am new to the DSM world! and ive been having this problem for a while now! I have a 1997 Eclipse Gst and it has a 14b turbo racing dejon front mount, turbo back exhaust, stock injectors, stock fuel pump... I am running about 12-13 psi... and when its in the high RPMs it hits fuel cut?.. also when you step on it it makes this weird noise some said its "like a bov for the waste gate" i dont know if this is true but it sounds pretty bad it doesnt sound right? does anyone have any idea what this could be?

Does it sound like this:

<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/FLkR-y13IM0&hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/FLkR-y13IM0&hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>

or this

<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/pqxJ5FyxbDQ&hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/pqxJ5FyxbDQ&hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>

 

[habitatguy187]

FIRST THINGS FIRST PEOPLE!

Do a boost leak test, go to this page - IC Pipe Tester and build one, then post the results.

Anytime someone's having fuel cut 95% of the time it's from a boost leak.

 

[eclipertnr90]

i brought my car somewhere to get it fixed some place that works on performance cars.. and it had a boost leak.. they said.. and they said they fixed it but it never stopped doing the noise.. idk its when you get past like 3 grand..and your flooring it or higher gears its a noise likee.. i cant even explain it haha.. and it hit fuel cut a lot earlier when the guy fisxed it now it hits in the higher RPMS..

thanks for all the responses

 

[habitatguy187]

Is it fuel cut or a bad misfire? Fuel cut will feel like your tranny just fell out of the car, almost like you hit a brick wall. If he fixed all your boost leaks then you shouldn't hit fuel cut at all, with that turbo at that boost level you should be able to go all the way up to redline smoothly.

BTW, how much did they charge you to fix it? And remember that you own a dsm, if you plan on continuing to mod it, you should learn how to work on your car yourself unless you have a lot of money.

 

[eclipertnr90]

haha yeahhh i know what you mean bro and no i dont have too much money i dont really have too much time anymore so i had them fix it.. i go to school full time at night and work 60 hrs a week as a car salesman.. so i unforunetly have like no time..

do you think getting like an AFC would help does anyone have any cheap?

 

[habitatguy187]

do you think getting like an AFC would help does anyone have any cheap?

No, I think you still have a boost leak and that you should take it back to them. Or maybe someone with some dsm knowledge in your area can help you out.

 

[98gsxtuner]

^^^^ I agree i would definitely have them redo the boost leak test, i had a bad one coming from where the blow off valve connects to the IC piping and i went to pass a car and just like he said it felt like my tranny fell out. I was really freaking out until i did the test fixed the leak and everything was good to go.

 

[rush2252]

How would low fuel pressure cause fuel cut at a lower boost level than a "good running" car which cuts at 17psi.

ugh.. im not going to get into arguments on here but ill explain a situation that was caused by a bad fuel filter. and no it wasnt in a DSM but that doesnt matter. Ill leave the make and model blank and try to explain where I was going with this one.

Me and a friend did a motor swap boosted the car etc. It ran great a few months later in 3rd gear only the car would fall flat on its face.. like fuel cut. It ended up being that at 5k or so this was when the fuel curve was at its peak and it was falling on its face losing pressure. It ended up being a clogged fuel filter. We changed it rechecked pressure and problem solved.


I usually speak with knowledgable ideas when im trying to help someone out on here read some of my posts I try to be descriptive and have spent hours and even given detailed drawing and wiring diagrams just because i know what its like to be there frustrated and not knowing what else to try. I also have access to alldatapro so i dont just blow smoke. It kinda irritates me when people are quick to point out mistakes and not justify their reasoning for doing so. This site isnt about proving people right or wrong its about pointing people in the right direction and not just taking guesses and have them waste their time and get frustrated. We are all DIYers at heart and any free good advice is better than bowing your head in shame as you take your car to some 50year old guy with two teeth and hand him your paycheck to tell you whats wrong with your car. Thats my two cents

 

[eclipertnr90]

yeah thank you very much for taking the time i was going to change the fuel filter... because it also when you come from a stop it doesnt just go back to a little under a grand.. it goes to like being shut off then starts....
like if you were to rev it then it would stall whether you had teh clutch in or not..

 

[habitatguy187]

yeah thank you very much for taking the time i was going to change the fuel filter... because it also when you come from a stop it doesnt just go back to a little under a grand.. it goes to like being shut off then starts....
like if you were to rev it then it would stall whether you had teh clutch in or not..

Definite symptom of a boost leak. A boost/vacuum leak will throw your a/f ratio off causing you to either run rich or lean, sounds like you're running rich since it wants to die when you give it more gas.

 

[dsm_Prince]

Ok this is my old car and that noise you hear is the external o2 dump.

 

[habitatguy187]

Ok this is my old car and that noise you hear is the external o2 dump.

 

[dsm_Prince]

Yea that was funny no one taught of that.

 

[eclipertnr90]

what is that normal?? the external wastegate dump

 

[wibblersnatch]

Does the O2 housing look similar to this? If so it has an what is referred to as a external dump. They make a lot of noise once you hit your desired boost level. They help eliminate boost creep.

You must be logged in to view this image or video.

 

[eclipertnr90]

yeah actually it looks just like that... alright i wasnt sure if it was supposed to make this noise because other turbo cars arent as loud as mine or i dont even notice them