Jump to content
The mkiv Supra Owners Club

Help me with fault finding - 2JZ-GTE won't rev - HKS F-CON Gold


Clausz
 Share

Recommended Posts

Hi everyone

 

After 2 years of rebuilding my supra, I have an slight issue. The engine won't rev above 3000 rpm, it seems like a limp mode or something like that. After a complete engine rebuild, new internal, new turbo, new intake, new injectors and so on. None of which shouldn't be relevant to the fault I'm experiencing.

 

It started by, I though it was due to the upgrade from 720cc low impedance to 1000cc high impedance. I went to my local tuner, experienced supra tuner, and after 1 hour of rechecking the map and further faults in the box he called me, and meant that the injectors was defect(or at least not giving fuel as 1000cc should). Wen revving the car hits 3000rpm and the lambda gauge goes lean (>22). I brought the car back and at first changed the injectors to 720cc, but no changes.

 

I made some videoes:

https://youtu.be/keZmox4NDjQ - engine revving and "limping" around 3000rpm.

https://youtu.be/WHOHz0z63mE - lambda guage going lean.

 

What I have already checked:

  1. Checked the HKS FCON for sensor faults = No one found
  2. Checked the Stock ECU for sensor faults = Found two knock sensors wasn't connected, fixed but no change.
  3. Checked voltage on injectors = 14,3-14,6volts
  4. Put ground on igniter module = no change
  5. Put ground on Resister box = no change
  6. Checked timing, 15-17 degrees in idle

 

I made two other findings, which I find strange.

1: When I pull the plug to the ECU water temp sensor, the engine is running a lot nicer and idles better. But still have the max 3000rpm issue.

2: If I start it immediately and rev it, it goes above 3000rpm, and then suddenly drops to 3000rpm. Please see video: https://youtu.be/rcY2tVbpBUs

 

So here is the complete list of things changed during the rebuild:

New internals

Changed from a aftermarket intake manifold to stock intake

Removed TRAC

Removed ABS

Moved fuse box to the rear compartment

New turbo

 

 

Anyone who has some great ideas of what to look for next? I'm loosing my courage with this issue.

 

Best Regards Claus

Link to comment
Share on other sites

Have you got the software to read sensors via the HKS ecu? Without having your own HKS ECU software you will find diagnosing this sort of thing near impossible if the fault is encoding in the ecu.

My tip is NEVER EVER buy an ecu that does not come with full control software if you intend any hands on engine work yourself.

 

Can you even go as far as pulling a log from it to send to your mapper?

Link to comment
Share on other sites

Hi Chris, I do agree. The car was bought with a HKS installed, and I therefore had no intentions of changing that, as it actually worked a couple of years ago. If I had the choice right now, I wouldn't fit a new HKS, there are so many other options.

 

I arranged with the mapper, that I will take the car out to him on thursday, and he will start faultfinding.

Link to comment
Share on other sites

I feel for you, these problems, when you have an after market ECU, leave you wondering if it's the ECU or an engine sensor fault. Once you can access the software for the ECU and read the sensors as the *ECU* is reading them, helps immensely. The HKS ECU is very competent for an old(ish) school one, but if o0nly the mapper can read data it's very limiting. An end user who just wants a map, and is happy to enjoy things, and just take it back to a garage with the software if things go wrong will not notice the difference, but if you are a "tinkerer" and like changing stuff, the lack of access to software is a *MAJOR* limitation. I hope you get it sorted soon, it's probably something quite simple to fix, once you find the problem.

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.

 Share

×
×
  • 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.