The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support Rix Racing
Please Support ExtremePSI

Need fuel system help

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

dsmaz

10+ Year Contributor
128
1
Apr 17, 2012
Bullhead City, Arizona
I was having some problems with my fuel system so i bought a bunch of goodies like a walbro fp, aeromotive afpr, fresh gas tank, and everything else i needed to redo my complete fuel system. Ok so i installled the newer fuel tank out of a 98 gs into my car with the wally fp hooked everything up although the 98 tank had some extra lines compaired to my 95 tank that i figured where the evap system and a couple extra vents. Installed my afpr how all the turbo 420a guys do and adjusted idle pressure to 50psi. When i drive my car in the low rpms its fine but when i start to make power it cuts out:ohdamn:. now i have looked over my entire system and have no leaks and my fuel pressure stays constant can anyone help point me in the right direction thanks. if you need more info just let me know

heres a video i just took of a cruise around the block. if you notice towrads the end when i rev my car in neutral the mph goes up too. idk if it could be a sensor, im gonna take my cam sensor off and clean it and see if that helps but any suggestions would help thanks.

https://www.youtube.com/watch?v=7-RbEEeiRMQ

so i cleaned my cam sensor and it did nothing. idk what it could be. i do have another set of injectors i could use to see if that helps because that is the only thing i did not change on my fuel system. If anyone has experienced something like this or has an idea of anything that i havent tried yet please feel free to comment.
 
This is my buddies car and as far as I know nothing has changed. When he revs the car in neutral the fuel pressure drops down around 30-35psi. I think he needs a different ecu but we never figured it out. Weirdest issue ever, he's close to 11.1:1 compression.
 
Did you remove the stock fuel pressure regulator when you installed the aeromotive one?? Also installed it like the 420a turbo setup, says your N/A still.. Lastly is there any check engine lights?
 
Stock regulator was removed. He has the afpr right off the firewall then going to the rail. Timing was dead on but still broke up past 4k pretty bad. We tried 21lb injectors then went back to stock with no difference. I thought it was ecu related but still haven't figured it out. Car idles great but breaks up in the power band.
 
When he revs the car in neutral the fuel pressure drops down around 30-35psi.

This leads me to believe there is a clog in the fuel system, since fuel pressure should rise as vacuum decreases. Changed the fuel filter lately?
 
Brand new filter and he put a second new fuel pump in it. But it wines really bad it never stops pumping since he has the return line hooked up. Which I always thought wasn't right but only 95 420a have that.
 
Brand new filter and he put a second new fuel pump in it. But it wines really bad it never stops pumping since he has the return line hooked up. Which I always thought wasn't right but only 95 420a have that.

i have fixed the whining pump problem i had a bunch of gunk in my tank that clogged up the pump and thats why it was whining. i put the tank from the 98 with a fresh wally.the 98 tank had the evap system in the tank when my 95 has the evap under the front end so i think the tank wasnt breathing properly. i have a 98 fuel rail with no regulator just the aeromotive after the rail hoked up to my own return line that i ran. i also installed a wideband and was running lean 11.5-12 at idle and would cut down to 10 when wot so i bought another fuel filter just incase that one got clogged up. i have 24lb mustang 5.0 injectors that im gonna use havent installed them yet though. but i have dropped the 98 tank and took pics of them side by side. ill post pics soon

also im going to blow out my fuel lines with my air compressor to get rid of any debris.
 
I'm hoping that will fix the problem I told you those stock injectors were to small LOL. They just opened up the drag strip in phoenix again so when you're ready we will line em up! You have to PM me your number I can never get a hold of you anymore on that other phone.
 
heres some pics of the tanks first pic is the 98 tank 2nd pic is 95 tank and the 3rd is the fuel float that is all rusted and thats what the inside of the 95 tank looks like. im gonna try to clean the 95 tank and put it back in but idk cause its kinda bad. the 98 tank i would use if i could figure out how to get it to vent properly cause it doesnt have a vent off of the fuel fill like my 95 tank does. in my hanes manual it says that all the tank venting in the 98 in controlled through the evap system and i did a evap delete

I'm hoping that will fix the problem I told you those stock injectors were to small LOL. They just opened up the drag strip in phoenix again so when you're ready we will line em up! You have to PM me your number I can never get a hold of you anymore on that other phone.

i got a new number so ill pm you. but they are building a 1/4 track in havasu. and also i know someone who is putting on a dyno day in havasu real soon so im trying to have my car running nice by then i hope. i want to see what kinda numbers i put down before a tune

here are some more pics of my afpr, my old pump that was whining, and then my new walbro 255 lph

So i totally cleaned out my 95 tank with a pressure washer and got it looking pretty dang good:D put my new pump with the new strainer, put in the new fuel filter, and also those 24lb injectors. And guess what i wish i could tell you it runs great but it doesnt:ohdamn:at this point im pretty aggravated and dont know WTF:notgood:can

here is a video of my wideband readings on a quick cruise
https://www.youtube.com/watch?v=GpNXFH6FJ14

and also here are some more pics of me installing the injectors and what not
 

Attachments

  • 98 tank.jpg
    98 tank.jpg
    54 KB · Views: 110
  • 95 tank.jpg
    95 tank.jpg
    43 KB · Views: 109
  • inside of tank.jpg
    inside of tank.jpg
    61.3 KB · Views: 103
  • afpr.jpg
    afpr.jpg
    31.3 KB · Views: 103
  • old pump (1).jpg
    old pump (1).jpg
    57.4 KB · Views: 131
  • new pump.jpg
    new pump.jpg
    36.7 KB · Views: 96
  • tanks.jpg
    tanks.jpg
    39.5 KB · Views: 103
  • injects.jpg
    injects.jpg
    42.6 KB · Views: 108
  • install.jpg
    install.jpg
    52.3 KB · Views: 102
Last edited:
well first off if your seeing 10:1afr on your wideband then your getting way too much fuel. the lower the AFR the richer(more fuel) you are getting. And this sounds like an ecu related fuel cut. I know the 95 ecu isnt supposed to have fuel cut but maybe some time along the road someone replaced it with a different ecu that has fuel cut. if you cant datalog then id put in a missing link or a cheap FCD to see if that fixes it
 
i accidently left the fuel pressure the same when i changed the injectors so i lowered it down to 30 even 20 psi and my wideband readings didnt change. why would my car be doin fuel cut? I have smaller injectors that are 200cc or 19lbs do you think that would work. Maybe its like a MAP sensor or something???? any ideas anyone

so i went to autozone and they scanned my car and got 5 codes.P1391,P0403,P0202,P0412,P1390. I think my injector wiring could be messed up im gonna replace the wring with another one i have lying around. Ill tell you guys how it goes later

ok so i installed the 19lb injectors with a new injector harness got everything hooked up and it ran the same. my wideband readings were the same.I took it back to autozone and it was only 4 codes this time and one of the codes was for the coilpack so im starting to believe that my coil pack or plugs n wires are messed up and thats why its reading so rich because the spark isnt strong enough to ignite all the fuel.
 
Last edited:
the codes for the second time i went to autozone were P0351,P0403,P0412,P1391. The first time i went the codes were for EGR,Air injection system,crank/cam sensor,timing jump,injector circuit cylinder #2. The second time i went to the zone after i changed the injects and inject harness my codes were for EGR,Air injection system,cam\crank sensor,Ignition coil primary circuit fault cylinder #1. Luckily when i went to the zone the second time i had warranty on my coil pack and plug wires so i traded them in and also got NGK platinum plugs to put in. When i got home i put everything on and checked my cam sensor and it had oil all over it. I guess the seal wasnt installed properly so i cleaned it off with a rag i had lyin around. Ill check it in a couple days and see if there is oil in there again. I think i might have a spare crank sensor somewhere in my garage. im going to look for that and then install it in my car and see if that fixes it or ill just go buy a new one. well after i find this sensor or whatever ill update and let you know if its a fail or not. IF this doesnt fix it than it must be an ecu related problem. If it does end up like that than im goin to have to go to the junkyard and buy this 98 gs 5spd harness,ecu and sensors that i saw while i was there. I do plan to go megasquirt really soon and im pretty sure that would fix my problem LOL
 
I went to autozone and got a new crank sensor and a new cam sensor cause it was cracked. Got home wired them in with there new connectors. I cleaned the cam magnet and area with carb cleaner and gave it a good wiping. After i installed the intake,battery and what not i put the key in the ignition and said a little prayer LOL. After i started my car my afr was at 14 so i went and up'd the pressure to 50 psi and my readings went to 13.2 at idle so i left it there. I got into my car and drove around the block and I pulled 1st gear all the way to 7k rpms and spun second. It was a good feeling to have my car running right and then all of a sudden it started cutting out again so i was like WTF!!!!!!!!! I went home and pulled the cam magnet off and it was covered in oil again so im guessing my cam seal is bad and my cam sensor cant get a good reading because of the oil so it doesnt know when to fire or inject fuel.
 
That's alot of progress man keep it up. You might have to torque down the cam sensor incase you are smashing or pinching it down to much. Or try tightening it just snug enough no quarter turn past snug. What kind of Wideband did you pick up?
 
That's alot of progress man keep it up. You might have to torque down the cam sensor incase you are smashing or pinching it down to much. Or try tightening it just snug enough no quarter turn past snug. What kind of Wideband did you pick up?
I ended up getting an innovative lc-1 like yours LOL. I took my cam sensor and magnet off. I noticed after i took them off that the oil was comin from behind the camshaft its self almost like the caps havent been tightened all the way down so im going to take my valve cover off and see if i can tighten it up a lil bit or something:hmm:
 
When is the last time you replaced your VC gasket? Only reason I ask is some people that replace it forget to put sealant on some portions of the valve cover gasket area. If you did replace it recently, may be a possibility.
 
You know what's funny is I recently found out that they came out with a lc-2 which is the same thing but it doesn't have to free air calibrate. Which is bad ass it does it on the fly pretty much with electronics.
 
When is the last time you replaced your VC gasket? Only reason I ask is some people that replace it forget to put sealant on some portions of the valve cover gasket area. If you did replace it recently, may be a possibility.

All of my gaskets are new but i have noticed that my valve cover gasket has been leaking all over the place. When i took my vc off to look at the the top of the head i noticed a bunch of oil down on my alternator bracket and lower intake manifold. Im going to go buy a new one and seal the entire surface this time LOL. hopefully that will fix the problem im having cause When i went to autozone earlier today the only codes that came up were egr and air bypass injection system so i think im pretty good with no more broken sensors.

You know what's funny is I recently found out that they came out with a lc-2 which is the same thing but it doesn't have to free air calibrate. Which is bad ass it does it on the fly pretty much with electronics.

thats pretty cool. so whats the status on your car jayson? did you put that spare motor in????
 
Dont do the whole surface good lord.. there is a write up on 2gnt that has a pic of where exactly to put just a few spots and that's all that is needed. Picture where to put silicone is at the bottom - 2GNT.com - Replacing_valve_cover_and_spark_plug_gaskets

Also I take it your EGR code is being thrown because you have it blocked off correct?

ya i have block off plates and pulled the sensor out. Im looking into getting a resistor to plug into it. the reason im thinking about doin the whole surface is because its literally getting oil all over the place its even all over the pressure guage on my regulator but i will check out the link fosho thanks for that
 
Guess the choice is yours. I literally just rebuilt my engine and followed that when I was putting my valve cover on and I have no leaks anywhere. So I would assume your gasket possibly didn't get lined up in the groove properly and as I said because you didn't put the silicone on the specified areas.
 
Guess the choice is yours. I literally just rebuilt my engine and followed that when I was putting my valve cover on and I have no leaks anywhere. So I would assume your gasket possibly didn't get lined up in the groove properly and as I said because you didn't put the silicone on the specified areas.

i agree with you totally im gonna check that out and do it that way n see what happens LOL
 
Hopefully it fixes your leak, did you also check the torque on your cam caps while you had the valve cover off just to make sure everything was to spec?
 
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top