Walbro fuel pump for 380?

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Aaron95j
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Posts: 57
Joined: 14 Oct 2014, 22:30
State: New South Wales
Model: Mitsubishi 380 SX
Engine: 3.8-Litre 6G75 V6 24V SOHC
Transmission: 5 Speed Manual

Walbro fuel pump for 380?

Post by Aaron95j » 04 Feb 2017, 12:43

Hey everyone.
I'm still having troubles with the 380 being jerky during a shift, and just recently its started doing it at random times. So a few times now it feels as though I've jumped off and then straight back on the accelerator again. It just jolts like it loses all power for a split second and then picks up again. Is this a clear symptom or a misfire?

A mechanic at work said they'd look at the fuel pump first and I've seen at least one case with a Walbro pump installed in a 380. I can't find one specifically for the 380 but something led me to a Universal Walbro pump so I'd just like to confirm the GSS342 is the one for a 380. Ebay is also flooded with fakes so should I go straight from Walbro?

And finally is this the first thing you would look at for these symptoms? Or should I be looking elsewhere before forking out money?

Thanks.

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Dougal
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Posts: 1212
Joined: 16 Mar 2011, 21:41
State: New South Wales
Model: Magna TS 1995
Engine: 3.0-Litre 6G72 V6 24V DOHC
Transmission: 5 Speed Manual
Location: Sydney, North West

Re: Walbro fuel pump for 380?

Post by Dougal » 05 Feb 2017, 13:27

I used a Walbro 255l pump in my TT car and had misfire jerkyness and swapped in a Aeromotive 340l pump

It did not fix it.

I also swapped in colder spark plugs as the ones i had were too hot for a turbocharged motor. This helped a little.

Also swapped in MSD ignition wires. Which again helped however has not fixed it 100%

My engineer on Friday hedged his bets on my coil pack being the culprit.

As you have a 380 with Coil on plug. It might simply be a failed coil.

Can you get some running datalogs for it to try and pinpoint which cylinder/s that are missing?
Its then far easier to just replace one coil or two coils than all of them
ModifiedMitsubishi /// Administrator

Proud owner of
2nd gen Magna TS 1995 - 3lt Twin Turbo 6G72 DOHC 5spd manual)
3rd gen Magna TJ VRX 2002 Wasp Yellow 6g74 SOHC

Aaron95j
Member
Posts: 57
Joined: 14 Oct 2014, 22:30
State: New South Wales
Model: Mitsubishi 380 SX
Engine: 3.8-Litre 6G75 V6 24V SOHC
Transmission: 5 Speed Manual

Re: Walbro fuel pump for 380?

Post by Aaron95j » 05 Feb 2017, 15:43

Thanks Dougal, I would be able to get work to look at it, unless I'd need a mitsi specialist?

The only repeatable symptom is the lag though, is that going to show anything up?

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Dougal
Administrator
Posts: 1212
Joined: 16 Mar 2011, 21:41
State: New South Wales
Model: Magna TS 1995
Engine: 3.0-Litre 6G72 V6 24V DOHC
Transmission: 5 Speed Manual
Location: Sydney, North West

Re: Walbro fuel pump for 380?

Post by Dougal » 06 Feb 2017, 08:17

If your local mech has a MUT scanner then yes i believe so. Hopefully not having to take to Mitsu as that sounds expensive.

By analyzing the fuel trims (Short term fuel trims and Long term fuel trims) you can identify which bank of cylinders (front or back) are misfiring as those particular cylinders will have rich fuel readings and the fuel trims in the ECU will show negative.

Basically speaking the o2 sensor for that bank will read the fueling as rich at the misfire point and the Engine ECU will compensate for that by pulling fuel enrichment back and not adding as much for that bank at that time.
The motor would not actually be running rich but rather the ECU thinks it is all because of the misfire at that point.

It could be as simply as a bad coil, bad spark plug or an injector sticking open at that point of the load range when your driving.
ModifiedMitsubishi /// Administrator

Proud owner of
2nd gen Magna TS 1995 - 3lt Twin Turbo 6G72 DOHC 5spd manual)
3rd gen Magna TJ VRX 2002 Wasp Yellow 6g74 SOHC

User avatar
Dougal
Administrator
Posts: 1212
Joined: 16 Mar 2011, 21:41
State: New South Wales
Model: Magna TS 1995
Engine: 3.0-Litre 6G72 V6 24V DOHC
Transmission: 5 Speed Manual
Location: Sydney, North West

Re: Walbro fuel pump for 380?

Post by Dougal » 06 Feb 2017, 08:22

Just a thought as you have had the lag thing going on for a while now.

Have you had the ECU learned vales reset at all with an MUTIII unit?

Im just about to look up to see if my Open port 2.0 cable is capable of doing this for you. Saving you a trip to Mitsubishi
ModifiedMitsubishi /// Administrator

Proud owner of
2nd gen Magna TS 1995 - 3lt Twin Turbo 6G72 DOHC 5spd manual)
3rd gen Magna TJ VRX 2002 Wasp Yellow 6g74 SOHC

Aaron95j
Member
Posts: 57
Joined: 14 Oct 2014, 22:30
State: New South Wales
Model: Mitsubishi 380 SX
Engine: 3.8-Litre 6G75 V6 24V SOHC
Transmission: 5 Speed Manual

Re: Walbro fuel pump for 380?

Post by Aaron95j » 08 Feb 2017, 16:38

No I haven't had the values reset. I work at a dealership and get half price labour there, they don't do Mitsubishi though so no MUT3. I didn't consider another local mechanic so I'll see if I can get that at a reasonable price.
I might be able to get my hands on some second hand coil packs and other parts cheap, flying to Melbourne tomorrow morning and taking a look at a wrecker while I'm there. I don't know if there's a catch but prices there seem too good to be true compared to home xD
Anyway I'll let you know what I come up with.

Thanks again

Aaron95j
Member
Posts: 57
Joined: 14 Oct 2014, 22:30
State: New South Wales
Model: Mitsubishi 380 SX
Engine: 3.8-Litre 6G75 V6 24V SOHC
Transmission: 5 Speed Manual

Re: Walbro fuel pump for 380?

Post by Aaron95j » 16 Feb 2017, 21:47

Okay so I have 3 coil packs, does it matter if they look a little dirty? One was in pieces and they were more expensive than another yard I was looking at, so I took 3.
No injectors left.

I can play around with these in a few days when I'm home.

Aaron95j
Member
Posts: 57
Joined: 14 Oct 2014, 22:30
State: New South Wales
Model: Mitsubishi 380 SX
Engine: 3.8-Litre 6G75 V6 24V SOHC
Transmission: 5 Speed Manual

Re: Walbro fuel pump for 380?

Post by Aaron95j » 02 Apr 2017, 22:38

I think I just heard pinging for the first time. Great.
Also, Mitsi want over $100 to reset my ecu so nah..

I already have the car booked in Wednesday to have injectors cleaned, I'll get them to install the coil packs if they can do some testing of some sort. Turns out they can't read the fuel trims on these though.

So a light tapping sound, consistent but relatively slow compared to the engine speed. Also an inconsistent sounding exhaust. Ping?

Thanks for the help.

User avatar
Dougal
Administrator
Posts: 1212
Joined: 16 Mar 2011, 21:41
State: New South Wales
Model: Magna TS 1995
Engine: 3.0-Litre 6G72 V6 24V DOHC
Transmission: 5 Speed Manual
Location: Sydney, North West

Re: Walbro fuel pump for 380?

Post by Dougal » 13 Apr 2017, 06:51

Ping or knock is relative to engine speed.

If its not the same or a similar speed then its likely to be something else thats rattling (perhaps exhaust bolt loose or something)

I dont know if the 380 came with a knock sensor (i know 3rd gen magna 6g motors did not)

Knock sensor would tell you if it was pinging,

Other ways to test are with det cans or knock ears. Basically a microphone tuned to knock frequency.
There are knock devices that is sold by Gizmo (see online)

Its frustrating trying to sort out small gremlins like this. Hope you figure it out
ModifiedMitsubishi /// Administrator

Proud owner of
2nd gen Magna TS 1995 - 3lt Twin Turbo 6G72 DOHC 5spd manual)
3rd gen Magna TJ VRX 2002 Wasp Yellow 6g74 SOHC

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