Just installed a walbro 190 and Im still getting fuel cut! Im only running 9-10psi on a rebuilt t-25 made into a t-28 ported. I have a ported exhaust manifold, intake, N1 o2 back and a few other irrelevent mods but am still on stock fuel setup and side mount i.c. ,for now. (except for the fuel pump) I am gonna rewire it, just thought Id drive it before and after the rewire to see for my self the benefit, but anyway I dont think I should be fuel cutting at 9psi on a otherwise stock turbo the only differince is I got upgraded wheels and porting. I know everyone is gonna say "boost leak test", hell thats the first thing I said too, but after finding a couple leaks and fixing them I dont know what else to do. Im going to a local awd dyno in few weeks to tune an afc that Im gonna be installing, but if I have other problems I want to fix them first. Now I know tunnig might fix it, but should I need it @ 9-10psi????????

Fuel Cut has nothing to do with fuel, it has everything to do with the amount of airflow the ECU is seeing.

In order for the MAF to be reading enough airflow at 9psi to make you hit fuel cut, you must have a boost leak.

I cant find any though.......I had to replace the throttle body gasket, but that didnt change anything. It didnt start doing it till I installed my down pipe....of course

What type of boost gauge are you using? How are you checking for boost leaks?

well I checked a while ago, pumped air into the turbo with a rigged up coupler and pump, my friends tester, which he doesnt have any more for some reason. it has something to do with the open exhaust since it happend after the down pipe install. unless that just helped another problem surface, thats what Im thinking. The gauge is a Faze, came with the car. I even compared it to my friends auto meter and got the same reading. Also Ive been hearing a wierd noise lately, seems like its coming from the intake mani. I know thats rediculous. Its one of those noises you have to hear, cant duplicate in words. happens when the car gets hot (operating temp).

CanadianTSi said:

Fuel Cut has nothing to do with fuel, it has everything to do with the amount of airflow the ECU is seeing.

In order for the MAF to be reading enough airflow at 9psi to make you hit fuel cut, you must have a boost leak.

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but isnt it a combination of the 2, air and fuel? I thought if the ecu reads too much air and not enough fuel to compensate then it would cut. I guess its more a tuning issue

I guess Im so stumped because on my last dsm with about the same mods and a big 16g I was able to run about 14psi untill upgrading the fuel system and tunning

I guess it all comes down to more $! Im at that point were you have to buy so many things. I just want this paticular car to be a quick daily driver and didnt want to dump alot of money in it. Looks like to me you just cant run a open exhaust with some sort of fuel system upgrade and tuning. (if you want to run some high teens psi. I mean I guess Im stuck untill I can get either dsm link or safc, but see then I need a wide band, injectors, might as well get a front mount, the list goes on and on.........
If the tuner companies wouldnt rape us on parts I might could LIVE! Im just broke

skinnykenny84 said:

well I checked a while ago,

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How long ago? If its been a while it could be leaking now

skinnykenny84 said:

Also Ive been hearing a wierd noise lately, seems like its coming from the intake mani.

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Could be a leak at the intake mani.

skinnykenny84 said:

but isnt it a combination of the 2, air and fuel? I thought if the ecu reads too much air and not enough fuel to compensate then it would cut. I guess its more a tuning issue

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It is solely based on how much air the maf is reading, has absolutely nothing to do with fuel. Just like CanadianTSi said.

^ I meant (with out) some sort of fuel system............

I know you all are right, and I should of known better, matter of fact I do. I just didnt want to face the facts!!!! I hate doing boost leak tests, always turns out to be more $$$. .
I just dont see why I didnt have a problem till I did the down pipe? Like I said before that just probably helped an existing problem show up.

Rig your own boost leak tester up for $10-$15. go to a free tire pump at a local gas station and never pay another dime again!!! There's no excuse that a down pipe caused fuel cut w/ a t-25.

made the boost leak tester!
Ran out of time tonight, just need to put air to it. I took the vfaq and tweeked it a lil and used what I could find, looks great. Last time I did this it was the throttle body gasket, that was the only leak I found. That was about 3. weeks ago, I guess thats why I thought it was something else. Hoping something new shows its face

Rig your own boost leak tester up for $10-$15. go to a free tire pump at a local gas station and never pay another dime again!!! There's no excuse that a down pipe caused fuel cut w/ a t-25

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.

must of been that little hang over I was sportin this morning I should of done this hours ago!

whats up with that quote^ ???
weird

Found more leaks! Throttle body gasket on both sides, both of these are new. The idle screw is leaking, and my intercooler was leaking. At first just the smic was leaking, untill I replaced it! Then the others showed up. Once I replaced the side mount the entire car ran better. The boost automaticly rose to 15psi from 9 with no FUEL CUT!

Nice job. Glad its working right now.

so you had to replace the entire SMIC, there was just a hole or something? ### I had this problem, and then my engien blew, replaced it, problem was still there. fuel cut LIKE ISSUE, at like 3500-4000 rpm. Is that what your problem was??

exiletalon said:

so you had to replace the entire SMIC, there was just a hole or something? ### I had this problem, and then my engien blew, replaced it, problem was still there. fuel cut LIKE ISSUE, at like 3500-4000 rpm. Is that what your problem was??

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ARE YOU HAVING A FUEL CUT ISSUE ALSO? Excuse the caps. Or a fuel cut like issue, describe it please. Mark

When I got my car the smic was bent over a little bit. The previous owner didnt do the lower ball joint recall so it broke and the tire hit the intercooler, but it wasnt that bad. Well I do a boost leak test and all I can find is the throttle body gasket on both sides (I.C pipe and Intake mani) so I got new gaskets even thought they looked good (metal) replaced them and still was hitting fuel cut @ 9-10pi, so thats how we go to this point. Do another boost leak test^ and hear air rushing out my intercooler so fast it wouldnt even hold a pound. Now after I replace that the t.b. gaskets and the idle screw is leaking :-( why do the t.b. gakets leak so easy and their metal? Im gonnna try some cork material and make my own and possibly use that and the metal ones????? I guess the idle screw just needs an O ring. Car runs pretty good though just to have exhaust, filter, uicp, clutch/flywheel. 13.3 in the 1/4 90degrees and spinning!

ya, my issue was there before and after I changed my engine out, it goes to 3500-4000 rpm, and cuts, ( feels like it hits a wall) - in every gear, 1-5, its still there. I boost leak tested it with a bike pump, the pump guage goes to like 20psi and then drops immediatly to zero, I hear a sound, but it sounds like its leaking from the boost leak tester itself. This is on my new 91 VR-4, I have a TSI but it never gave me crap, turbo is S16G, Greddy hard pipes, Stock SMIC.- 12PSI- autometer gauge

Ok, I have no boost leaks and fuel cut is back! The only mod thats diff from before is the addition of a supra smic. I think I have maxed out my stock injectors. I guess Im gonna go ahead put in some 560cc's and an eprom chip, since I have a eprom ecu just sitting here.

Got alot of maintince to do untill then. I feel like I need a timing belt since Im not 110% shure the previous owner did one on time. Might as well do the balance shaft eliminator and fix a few oil leaks. How do you guys feel about aftermarket timing belts? ie: Greddy etc.. or should I just go with the oem Mits belt?

Need brakes all the way around too. Has anybody bought the e-bay cross drilled and or slotted rotors? like these.......
http://cgi.ebay.com/Eclipse-Galant-...5QQihZ020QQcategoryZ33564QQrdZ1QQcmdZViewItem


http://cgi.ebay.com/Mitsubishi-Ecli...8QQihZ005QQcategoryZ33564QQrdZ1QQcmdZViewItem

http://cgi.ebay.com/Eclipse-GSX-GT-...1QQihZ002QQcategoryZ33564QQrdZ1QQcmdZViewItem

oh yea, forgot to add. Its not fuel cuttin at 9psi no more, more like 15psi.

Are you expecting a different answer?
Short of a getting a EPROM ECU and a chip or DSMLink the only thing you can do is make 100% sure you don't have any boost leaks at the highest boost pressure you want to run and get bigger injectors so you can lie to the ECU with a SAFC or MAFT about how much air is being metered.

Your not done with leak testing until you can hold the pressure for at least 30 seconds without any additional air.

Steve

I didnt time it as I was busy looking and listining for leaks but it seemed it was at least 20 sec or more.

and are you saying not go with the eprom and use an afc or maft? you confused me on that one.

I already have an eprom waiting to be socketed so Im sure I want to go that route.

the only leak I found was the idle screw (o ring) when I spray soapy water around it it will bubble slightly......very slowly.

If I turn the boost down a couple pounds or if its hot as hell It wont fuel cut. So its deff senstive.

Ok, I have no boost leaks and fuel cut is back! The only mod thats diff from before is the addition of a supra smic. I think I have maxed out my stock injectors. I guess Im gonna go ahead put in some 560cc's and an eprom chip, since I have a eprom ecu just sitting here.

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Humm, you still don't understand what everyone is trying to tell you. Hitting fuel cut has little to with your ability to deliver fuel, it's there to guard against run away boost, not fuel starvation. Try and think of it as the gas pedal which controls air flow, not fuel.

How many psi did the boost gauge register during your boost leak test?

skinnykenny84 said:

Are you saying not go with the eprom and use an afc or maft? you confused me on that one.

I already have an eprom waiting to be socketed so Im sure I want to go that route.

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No I'm just telling you what the various options are:
EPROM ECU with DSMLink or custom EPROM or SAFC or MAFT and larger injectors to either eliminate fuel cut or pospone it a bit.

Steve