Jump to content
The mkiv Supra Owners Club

Fuel pump ECU


HTSmak

Recommended Posts

Been having troubles with my supra for a few years now, it could happen within days, weeks or months, the car will be idling or during the drive just turn off completely. I cant turn it back on unless i unplug the fuel pump ECU in the boot and plug it back in ( may take 2 or 3 times ) before the car starts again, I've even bought another ECU and the problem still happens. About 5 or so years ago I did have the fuel pump changed to a Walbro E85 compatable pump ( all thats written on the paper from the mechanic ). Wondering if theres a way to directly wire the fuel pump ECU into my wolf v550 ECU or what else can I do ?

 

 

Link to comment
Share on other sites

Bin the lot and get a more up to date ecu , control everything

 

LINK/Haltech/EMU Black are reasonable ; have a chat with your tuner what meets your needs

I dont have a tuner where i live, it was sent 1000 kilometers away to get tuned and he put the wolf v550 ecu in. What about the fuel pump ecu in the boot, can i hard wire that and remove that ecu or ? Is it maybe the walbro fuel pump aswell ?

 

 

Link to comment
Share on other sites

Fuel pump is very simplistic , controlled by a relay(s) ; basically an on/off switch. The main ECU i.e. the wolf controls when the fuel pump(s) based on fuel demand

 

Looking at the V550 spec's , it is capable of controlling the pump(s)

 

No idea what this other fuel pump ECU in the boot is? or why it is needed

Link to comment
Share on other sites

Fuel pump is very simplistic , controlled by a relay(s) ; basically an on/off switch. The main ECU i.e. the wolf controls when the fuel pump(s) based on fuel demand

 

Looking at the V550 spec's , it is capable of controlling the pump(s)

 

No idea what this other fuel pump ECU in the boot is? or why it is needed

Well its a stock ecu, theres about 15+ small ecu's throughout the car that all go to the main ecu

 

 

Link to comment
Share on other sites

Well its a stock ecu, theres about 15+ small ecu's throughout the car that all go to the main ecu

 

/QUOTE]

 

You need to get pics , if they are relays , no idea why you need 15!

 

It sounds like something is tripping but not enough to cause a fuse to blow

 

Wolf is a standalone ecu with a pnp harness for the Supra , unless you are using the OE ECU to control the stock Auto trans (Wolf states it can control) , no reason you would keep your stick ecu , unless you are referring to the Traction control ecu, resides beside the main stock ecu

Edited by Jellybean (see edit history)
Link to comment
Share on other sites

You need to get pics , if they are relays , no idea why you need 15!

 

It sounds like something is tripping but not enough to cause a fuse to blow

 

Wolf is a standalone ecu with a pnp harness for the Supra , unless you are using the OE ECU to control the stock Auto trans (Wolf states it can control) , no reason you would keep your stick ecu , unless you are referring to the Traction control ecu, resides beside the main stock ecu

No they arnt relays they're actual ecu's, the manual states so, the stock main ecu is no longer in the car.

 

 

Link to comment
Share on other sites

No they arnt relays they're actual ecu's, the manual states so, the stock main ecu is no longer in the car.

 

/QUOTE]This is the ecu for the fuel pump, i found an article of someome bypassing the ecu which ill postimage

 

Sent from my SM-G950F using Tapatalk

Link to comment
Share on other sites

This is the ecu for the fuel pump, i found an article of someome bypassing the ecu which ill posthttps://uploads.tapatalk-cdn.com/20200305/e275ee6efec028aef72ab4023ad1fab9.jpg

 

/QUOTE].image

 

Sent from my SM-G950F using Tapatalk

Link to comment
Share on other sites

.https://uploads.tapatalk-cdn.com/20200305/3f2c6c046795dcb2b1896294b8adf7f2.jpg

 

/QUOTE]Bit blurry to read those but yeah, theres an ecu for the fuel pump but im not sure if this will fix the issue nor if i should try this ?

 

Sent from my SM-G950F using Tapatalk

Link to comment
Share on other sites

Says the page cant be found ?

 

/QUOTE]

 

It's because you haven't paid your membership, parts of the forum are closed off to non paying members. There is loads of technical stuff on the forum that would help you out.

 

If you go to the top right of your page and click on settings, then on the left of your screen you will see a list. Under My Account click paid subscriptions.

 

It's £10 per year or £30 for life :thumbs: Well worth it for all the knowledge that is held within these walls.

 

In the meantime i'll host the image so you can see it.

 

image

Edited by Frank Bullitt
Image added. (see edit history)
Link to comment
Share on other sites

JZA80 does not have a Fuel pump ECU ,

 

Looks like you have some form of OE Toyota relay installed (Fuel ECU) Soarer ; I presume you had this installed a long time ago

 

You will need to either have an auto electrician test the units are still working or take the car to a tuner to diagnose

 

At lease pull any logs from the ECU to see if you can identify the issue

 

If it was me , this ECU is from pre 2007 ; I would upgrade to a more modern ECU ; probably more cost effective after you go chasing gremlins plus you may find it difficult to find somebody familiar with the wolf, tech has come on light years since then

Edited by Jellybean (see edit history)
Link to comment
Share on other sites

Just as a point of interest really, the early LS400 1uz had a novel but very effective way of regulation. So in normal conditions the pump voltage ran through a series resistance dropping the voltage to about 9v then when the ecu called for more fuel a set of relay contacts co-located with the resistor bypassed the resistor and gave the pump full voltage. What made me think of it was that your photo looked very similar to the resistance they used.

Link to comment
Share on other sites

JZA80 does not have a Fuel pump ECU ,

 

Looks like you have some form of OE Toyota relay installed (Fuel ECU) Soarer ; I presume you had this installed a long time ago

 

You will need to either have an auto electrician test the units are still working or take the car to a tuner to diagnose

 

At lease pull any logs from the ECU to see if you can identify the issue

 

If it was me , this ECU is from pre 2007 ; I would upgrade to a more modern ECU ; probably more cost effective after you go chasing gremlins plus you may find it difficult to find somebody familiar with the wolf, tech has come on light years since then

Well the manual for my car 1995 jza80 twin turbo 6 speed model says its an ecu and theres lots of other smaller ecu's but thanks

 

 

Link to comment
Share on other sites

Just as a point of interest really, the early LS400 1uz had a novel but very effective way of regulation. So in normal conditions the pump voltage ran through a series resistance dropping the voltage to about 9v then when the ecu called for more fuel a set of relay contacts co-located with the resistor bypassed the resistor and gave the pump full voltage. What made me think of it was that your photo looked very similar to the resistance they used.
I know the car also has a really bad earth leakage cause the battery drains really quick when its not running, not sure if this could be affecting it

 

 

Link to comment
Share on other sites

JZA80 does not have a Fuel pump ECU ,

 

Looks like you have some form of OE Toyota relay installed (Fuel ECU) Soarer ; I presume you had this installed a long time ago

 

You will need to either have an auto electrician test the units are still working or take the car to a tuner to diagnose

 

At lease pull any logs from the ECU to see if you can identify the issue

 

If it was me , this ECU is from pre 2007 ; I would upgrade to a more modern ECU ; probably more cost effective after you go chasing gremlins plus you may find it difficult to find somebody familiar with the wolf, tech has come on light years since then

Also that fuel pump ecu was in the car when i bought it

 

 

Link to comment
Share on other sites

Ok so first of all let's clear up some misinformation. Both NA and TT Supra's use a fuel pump ECU from factory, located in the boot of the car. The NA and TT fuel pump ECU's are different, but effectively perform the same job. Although the TT units are stouter as they need to handle more load compared to NA.

 

The TT fuel pump ECU's basically take a 12V feed from EFI#2 Relay, then output either a 9v or 12v feed to the fuel pump ECU depending on if the stock ECU commands a low load or high load situation via the use of a PWM 5v signal.

 

The first thing you need to test if you think your fuel pump ECU is on the way out is the following.

 

Switch your ignition on, but don't turn on the engine. Go into your engine bay, find the diagnostics port and bridge FP & B+ using a piece of wire. Bridging this puts the fuel pump ECU into test mode and will cause it to run at 12v continually. You should hear your fuel pump kick turn on, even if the engine is off.

 

If your fuel pump does not kick on after doing this then you know you either have a wiring fault or the fuel pump ECU is faulty.

 

Not all aftermarket ECU's can play nice with the stock fuel pump ECU. Typically when using a standalone we always replace the fuel pump ECU with as relay, as some other members have described above.

 

I have never used a Wolf ECU before so can't comment on it's compatibility with stock fuel pump ECU. But I would imagine if you needed to setup a fuel pump relay, then you just need to wire either a grounded or 12v output from the Wolf ECU to trigger a relay for the fuel pump.

 

Some aftermarket fuel pumps also don't like being run at 9V, usually requiring a minimum of 12v to be running troublefree. So this could also be a possibility depending on whats been installed in your tank.

 

Start with the diagnostic port and see what it does then report back.

Link to comment
Share on other sites

Ok so first of all let's clear up some misinformation. Both NA and TT Supra's use a fuel pump ECU from factory, located in the boot of the car. The NA and TT fuel pump ECU's are different, but effectively perform the same job. Although the TT units are stouter as they need to handle more load compared to NA.

 

The TT fuel pump ECU's basically take a 12V feed from EFI#2 Relay, then output either a 9v or 12v feed to the fuel pump ECU depending on if the stock ECU commands a low load or high load situation via the use of a PWM 5v signal.

 

The first thing you need to test if you think your fuel pump ECU is on the way out is the following.

 

Switch your ignition on, but don't turn on the engine. Go into your engine bay, find the diagnostics port and bridge FP & B+ using a piece of wire. Bridging this puts the fuel pump ECU into test mode and will cause it to run at 12v continually. You should hear your fuel pump kick turn on, even if the engine is off.

 

If your fuel pump does not kick on after doing this then you know you either have a wiring fault or the fuel pump ECU is faulty.

 

Not all aftermarket ECU's can play nice with the stock fuel pump ECU. Typically when using a standalone we always replace the fuel pump ECU with as relay, as some other members have described above.

 

I have never used a Wolf ECU before so can't comment on it's compatibility with stock fuel pump ECU. But I would imagine if you needed to setup a fuel pump relay, then you just need to wire either a grounded or 12v output from the Wolf ECU to trigger a relay for the fuel pump.

 

Some aftermarket fuel pumps also don't like being run at 9V, usually requiring a minimum of 12v to be running troublefree. So this could also be a possibility depending on whats been installed in your tank.

 

Start with the diagnostic port and see what it does then report back.

Thanks a lot

 

 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.