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HELP! Bad gas? (logs and now VIDEO)

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Have you verified there isn't a voltage drop to the pump when this occurs?

Watched voltage across the pump. Hits 12.08V fast then rises to 12.12 ish within a sec or so then stays steady. I tested across the pumps power feed and a chassis ground. I also switched it on and off a bunch with while varrying duration from a second to a min or so. No real voltage drop across the pump. Maybe I'm doing that test wrong tho?

Switch the map sensor with a working one. I had this issue of going lean at idle ended up being a bad Omni 4 bar.

Did you watch the video? I'm pretty sure its the pump now. Could the OMNI 4 bar somehow be messing the pump up?
 
I concur that it is really cold out there for you to work on your car this last week.
I was out there today parking the talon outside for the winter to get the garage stall back and the cold sucks.
Good luck with the fuel issue. I can't wait to find out what the issue is.
You planning to drive the car this winter?
 
I concur that it is really cold out there for you to work on your car this last week.
I was out there today parking the talon outside for the winter to get the garage stall back and the cold sucks.
Good luck with the fuel issue. I can't wait to find out what the issue is.
You planning to drive the car this winter?

I'm still polishing off my HE351VE controller and I ran out of summer so I'm gonna have to run her a lil bit. The controller is so damn close....i was hoping to do the final PCB over the winter. :(

I put winter shoes on it and this issue popped up. Roll with the punches.

Okay I'm dumb.....the pump was running out of fuel b/c the tank was low from being jacked up. Fuel gauge wasn't picking it up that it was empty. Disregard vid as it was out of fuel. SMH. Ops.

Put in the Wally 190.....same issue. Does its warming thing and then slowly leans out.
Switch the map sensor with a working one. I had this issue of going lean at idle ended up being a bad Omni 4 bar.

I will try and diff map sensor for sure....if not just to check off that the OMNI isn't leaking internally.

NEW TESTS on wally 190:
- capped mani to VC (even tho it BLT fine) to isolate more....no change.
- capped off boost gauge (even tho it BLT fine) to isolate more....no change.
- capped off cyclone mani solenoid feed on the mani (even tho it BLT fine) to isolate more....no change.

I have a spare ECU from the parts car that supposedly has link....not sure what version but I'll just swap chips if its not V3. That should eliminate that it's leaky capacitors or some other ECU issue.

Maaaaaaan I am REALLY running out of places to look."


EDIT: It's V2....at least it's socketed. :)
 
Switch the map sensor with a working one. I had this issue of going lean at idle ended up being a bad Omni 4 bar.

Changed out the Omni back to my GM3 Bar. No Change.

When it's leaning out are the pulsewidth changing?

How could I check that? From the logs duty is 0.8% at idle.... 2150's. The issue does sound injector-ie.....like one cylinder suddenly starts missing a bit from being way to lean. In the logs it looks sinusoidal or rather spikey as it starts to happen....then it just gets worse and worse until something is missing in one cylinder for sure. But not every rotation....very intermittent still and not cyclical like a plug wire failed or an injector is stuck closed.

Also I turned on knock to activate at 0% and 750RPM now too. I don't see any knock from a super lean cylinder. It does go wav-ie tho like it's only on 1 cylinder.

Update:
- changed out for a different ECU with the same V3 chip from the previous ECU. No change. I liked how easy it was to change tho.


Soooooo: different pump, ECU, MAP sensor, AFPR(and gauge), relay on the pump rewire.....also O2 re calibrated, boost gauge bypassed, cyclone solenoid bypassed, VC-2-mani capped off, pump is getting 12V steady, BLT to 35 psi with no leaks....NO CHANGE. Still goes lean real slowly and then starts missing (or something) intermittently but severity increases (in regards to AFR's) over time.

I'm thinking injectors now maybe? Maybe it is ignition? I have spare shiiiit there too so I'll swap stuff around tomo morning.

Maybe it could still be bad gas...but I feel that's a cop out or a stretch. It would still run right at idle wouldn't it?


I have checked a loooot of stuff now. I'm gonna keep throwing darts here....but anyone else wanna chime in with ideas plzzzzzzz???? I am fuuuucking stuuuumped on this.
 
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Maybe the ptu is warming up and not working after awhile.

Ill swap around that and some ignition stuff this morning

Could it be the FIAV?
It still seems like something is warming up and stops working slowly.
 
Are you still using the easytune box? Could it be failing to give 17+v?

Yes im still on the easy tune.

I have been eyeing the injector box as the symptoms at idle kinda feel like when I didnt have the box and the big injectors just dont idle well. In my head ive kind of ruled out the box tho because at idle the dead time is super important as that 17 volts is what makes the big injectors work it's such a small pulse-width. However I'm getting that lean condition even when I'm reving up the engine to launch control limit or that one time I went around the block and getting in to boost a little bit and it's still going lean. At those rpms the dead time is contributing very little to the overall pulse-width. So I don't think it's the box but I'm going to check the voltage now that you mention it anyways. Always good to check another thing off the list of potential culprits. :)
 
UPDATE:
- diff PTU. No change.
- diff ig coils. No change.
- diff ign wires. No change.


Thoughts:
It still feels like its missing randomly either due to fuel or ignition. That being said I think my car has always done that at idle b/c of the 2150's but it feels like the car is slowly getting richer and then the 2150's doing there usual weird idle just exacerbates it further. I thiiiiink I am starting to see a correlation between the ISC closing upon initial startup down to it's target idle.

Gonna go and pull my TB and take apart the ISC and make sure it sealed. I'll test will its out too.
 
GOOD NEWS: I made it to fans kicking on and off and it stayed within +/- about 2-4% AFR's. I'm not gonna say it's fixed yet till I roll around the block and see what happen near boost kicking in.


UPDATE:
- Pulled the fuel rail and injectors and cleaned and inspected. Everything looked fine. Baskets clean. O-rings still 800 km fresh. Rail clear.
- took off the TB and tore down, inspected and cleaned FIAV and ISC. The FIAV looked gross inside and cleaned as best I could but I gotta pull the freeze plug to get in there good. The ISC however....when I rebuilt the TB last time I inspected the ISC and when reassembling realized the O-ring i had was wrong. I had a helluva a time getting the old one back in and it honestly seemed not-new-but-okay still. Sooooo just now I grabbed another o-ring one off a diff TB and doubled up on the O-ring. I forced that biiitch in there and torqued down the ISC until it was tight but not cracking the housing. I also pulled the ISC apart and it all looked good. I cleaned up the oring in there too.

I then started it and it came up to temp good. No leaning out thing. Still doing its weird idle hiccup thing b/c of the injectors but I was thinking about it and I prolly need to set the individual dead time and % for each one to get a smoother idle. I'm gonna go for a rip and see how it goes.....
 
Update:
Went for a rip around. Had a nearish empty tank (pumped most of it into jerries) and it was smoking weirdly. AFR's we're okayish in closed loop after i ran the auto VE tool. Filled up with fuel from my usual pump (94) and added some injector cleaner. Seemed to help with the smoking but the AFR's are still weird and I am getting rando knock at low load levels and low to mid RPM's. Maybe it really was bad gas that is just running like shiiit and gumming stuff up. The gas I pumped out did not smell very "gass-ie" I've pumped gas from sled's and stuff that got parked for a couple years and it smelled like that. Just old gas. I dunno tho.

Did some cruising runs to use the VE tool and I am getting weird values being suggested and its erratac. Add's in the cell one time then pulls from it the next. Also suggesting shiiit like 108% in cells that used to be 85-90. Clearly not 100% fixed.

The last thing it could be now is gummed up injectors or filter...or failing injector. I did check the filter visual but that is probably not good enough. My last ditch effort before sending the injectors off to get checked is flush the tanks a few times with gas and pump it out into jerries, swap the fuel filter, and then fill up with gas one last time. If that doesn't fix this shiiiit its gotta be the injectors. Maybe i shook loose something that was tripping the injector out or maybe it was dumb luck it started working (ish) again. I'm still on all the swapped stuff so:diff ecu, map, ignition stuff, etc, etc.
 
Sounds like you have had nothing but bad luck with the injectors specifically.

The 2150's been good to me so far. I honestly was rip around tuning, filled up before i parked it for the night and it was already acting werid after filling up. Nexr morning idle AFRs were outta whack and here we are. So i dunno...gas related maybe?
 
Update:
- swapped plugs and gapped to 27. No Change.


NEW INFO:

- I noticed in my logs last night that the batt voltages in link seemed high. They were 14.5-.7 at idle. Usually they are at 13.8-14.3.....depending on what side to 1000 RPM its on. But this morning i saw some preeeety steady 14.5-14.9 now that I am watching it.
- I pulled my Easytune box and measured voltages right inside the box (luckily they have giant solder points and labeled on the PCB) I checked the voltage in and the voltage out. Same as link bouncing right around 14.7....however I could see it drop down to 2-3 volts and pick back up quick. My multimeter is cheap and slow and if its picking it up then its QUITE the long voltage drop. Slight correlation between the sound I'm hearing at idle and the drop....but that droop should not happen at all.


Now I am thinking its the fuucking alternator (or charging circuit) this whole time. Maybe makes sense. Pump does sound weird and off and it still feels fuel delivery related. Igition is always missing and entire cylinder and you can see that and it shakes the motor a bit. If it is dropping volts at idle those 2150's are UNHAPPY with any change in deadtime when they are sitting at 0.8% duty. So it's dropping volts quick and messing up the fuel flow which is maybe why I am seeing such erratic behavior. I also can see the voltage drop on the Easytune Vout and it does drop down 2-3 volts as well.


EDIT:
- I was just thinking that it shouldn't be dropping to zero tho even if it was the alternator as the batt should supply 12V if the alt suddenly is dropping volts.... or does the Voltage reg for the charging system do that maybe? I'm outta my realm of knowledge with the charging system.
 
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Just a question, why are you running the easytune box with the 2150's? I just put 2150's in mine and got it to idle and run so good right before my crank pulley decided to come loose and kill the engine. They were easy to tune and ran so smooth. I never ran the easytune box but I did have to play with the injvoltoffset to get them to play nice. Just wanted to ask about the easytune box and have you tried the car without it?
 
Just a question, why are you running the easytune box with the 2150's? I just put 2150's in mine and got it to idle and run so good right before my crank pulley decided to come loose and kill the engine. They were easy to tune and ran so smooth. I never ran the easytune box but I did have to play with the injvoltoffset to get them to play nice. Just wanted to ask about the easytune box and have you tried the car without it?

I run the injector box b/c its *suppsoed* to supply a constant 17V to the injectors. Also it makes the deadtimes a snap. I just set my deadtime to 530 across the board b/c I know my injectors are getting 17V always and 530us is the exact deadtime they need. All the box is is a step up transformer with what I would assume is a bunch of filering to get that supply smooth as hell. It's worked so so awesome in the past but I will be looking at it closely.

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To be clear....I am getting voltage drops across the Vin which is fed directly from the OEM injector plug where the injector resistor used to be. That means the drop is happening whether the box is there or not. With the car off but key on I get ~12.4V (which more or less matches the voltage my audio systems capacitor is reading across the batt and also the voltage link is telling me) and it is steady.

I am removing the alt fuse and seeing if I get the same issue with the car running off batt power. I thiiiiink that eliminates the alt.

Maybe I am missing something tho....I am tired and cold from being at this for 3-4 days now. Whether the box is there or not; I don't think I should see a drop across when the engine is running right?

Looking at the circuit diagrams there is aloooooot stuff on that Vin that the Easytune also uses. Starts at the MFI relay out and feeds the injectors (via easytune box), ISC, CPS, CAS, the ECU's power source, EGR solenoid, FPS solenoid, EVAP solenoid, WG solenoid, MAF (I'm SD with IAT), and F/R O2 (I'm LC-2 no O2R).

Maaaaan thats a lotta stuff to check if something keeps rando shorting to ground. I still think its weird my volts are so high off the alternator tho....the electrical gremlin hunt begins.
 
FINAL UPDATE:
No one is gonna like this....I certainly did/do not....

- I had previously drained the fuel tank and mentioned it did not smell "gassie". It smelled like weak 2 yr-old gas that had been sitting in a quad or sled for 2 years. I know b/c I have drained my sled and quad after storage enough to know what old/bad gas smells like. We'll one "type" of bad gas anyways. I filled up with 20L of fuel from the same local store but a diff pump (or rather my usual pump). The problem continued....however it did show signs of improvement. I was switching around a lot of things so I lost track (or rather was unable to track) of what was improving what.

- Last night I picked up a new 10 micron filter element for my -6AN giant fuel fitler (which the Mopac guy also agreed did not look plugged or even dirty) and some Red Line injector cleaner. Talked with Mopac guy and he said (after listening to my shiit list of stuff I had checked and fixed) that maybe it reall was bad gas. He said he's gotten a few tanks of gas over the years and once he had dyno'd a 100hp less on his 500hp LS-something-something. As a finally stab at the prob I drained my fuel tank once again....this time as low as she'd go. I mean I got in the tank with a siphon hose (got a few mouth fulls of gas) and worked my around it untill the siphon wouldn't pick anymore up. I then blew down the main feed line reinstalled my "old" W400 pump and reconnected everything. I threw in the Redline cleaner and 20L of new fuel from a totally different station this time.



First startup went like usual....kinda okay but still being a bit weird. No leaning out anymore but you could hear it running a bit funny. Left it idling for about 30 mins. Shut it off twice so did 3 warm upof 10 mins with a small break to air out the garage (smoking strangely still). No leaning out. AFR's were close enough to stoich to say that there was a difference

Went for a cruise and it was still giving me rando knock on part throttle, felt a lil funny, but the AFR's were much better. Still a bit rando lean and not totally on target.....but better. Soooooo I filled up to 3/4 tank from the "new" station and went cruising for about 2 hrs. Did the ring road around my city with small spurts of boosting (lowered my limit to WG pressure which is 10psi) upto about 5-6K. The longer I drove the better it was getting. After about 20 mins the smoking on throttle slowly ceased, and the AFR's started lining up better. another 20 mins and no smoking and I could feel the power coming back a bit. Was pulling more smooth and stronger than before. Continued crusing around and it was getting better and better.....first the rando knock disappeared completely and then a little longer and the AFR's reeeeeeallly lined up. Took about 100km's of crusing but it's back to what it was. Open loop AFR's back on target and closed loop was cycling as it should about 14.7.

In the end it does it appear it was bad gas. I mean I checked every thing and swapped everything from tip to tail and the ONLY thing that made a really definable difference was the fuel. I do not like that it was the fuel as it feels like such a cop out. Oh well, it is what it is.

Thank you to all who contributed. I'm moving forward again. :)
 
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