2JZ GE 1996 Start Up Issues Help Needed To Save Car!

[J4AVX]

Hi all

I'm new here, I'm desperately looking for help.

I have 2JZ GE engine. Its actually an old Lexus GS300 1996 but shares same engine as non turbo Toyota Supra 2JZ GE.

The car starts up and cuts out within a few seconds. I've had distributor replaced, sparks replaced, ignition coil replaced, camshaft sensor replaced.

I've now hit a dead end the car is parked up now and I really want to get the car back on road. Taken it to multiple mechanics but the can't diagnose the problem.

Can anyone help or recommend anyone within West Midlands Birmingham area to take a look? 

I really don't want to scrap the car!

Any help is appreciated!

[rider]

On vintage cars, which the Supra now is, you hear/read this sometimes becoming an issue and it can be something simple like a worn ignition barrel. Maybe someone can give some tips on hotwiring the fuel and ignition circuits that would pinpoint if that is your problem. I could tell you how to hotwire an MGB but I've never tried it on a Supra.

[Scooter]

Does it start everytime for a short time, or just once then won't start?

You can try starting it without the aux belt on (only for a minute or so)

You could try bridging the terminals in the diagnostics port, the ones that run the fuel pump, then you could try it (again only for long enough to test if that's made a difference) If you bridge the right terminals you'll here the fuel moving when turning on the ignition. 

These are things that might rule things in/out. Chris Wilson on here would say the mechanics need to be more old school and have scopes etc to tell precisely what's going on.

Have you done the procedure to get any engine codes?

 

[Scooter]

toyota codes  https://www.facebook.com/watch/?v=3040080559355374

Fuel terminal info

 

[Probby]

Sounds like a coil(or coils) aren't sending back an IGF signal to the ECU and the ECU is killing the engine. If it's running good (allbeit briefly) that would be my first guess on the limited info you've given. 

That could simply be down to corroded/bad connectors between the coolpacks and ECU. Check those and clean if they look coroded inside (e.g. rust/corrosion) bit of isopropyl alcohol and a decent brush which can get in there should do it. 

This is worth a read. https://automotivetechinfo.com/2021/07/how-to-find-toyota-ignition-system-faults-fast-dotting-the-igfs-and-crossing-the-igts/ 

Good luck

[J4AVX]

9 hours ago, Probby said:

Sounds like a coil(or coils) aren't sending back an IGF signal to the ECU and the ECU is killing the engine. If it's running good (allbeit briefly) that would be my first guess on the limited info you've given. 

That could simply be down to corroded/bad connectors between the coolpacks and ECU. Check those and clean if they look coroded inside (e.g. rust/corrosion) bit of isopropyl alcohol and a decent brush which can get in there should do it. 

This is worth a read. https://automotivetechinfo.com/2021/07/how-to-find-toyota-ignition-system-faults-fast-dotting-the-igfs-and-crossing-the-igts/ 

Good luck

Thank you for your response.

I'm not really just of a technical guy when it comes to cars. Sorry for the silly question but where are is the ECU located? Any diagrams or pics of where I should be looking? 

My last option is to book it in with Lexus dealers to diagnose the fault but I'm worried they will charge me a lot of labour money and may not even be able to fix...

[Probby]

You're not really looking for the ECU at this point, more concentrating on the connectors on top of the coil plugs themselves and anything back towards the bulkhead of the car. 

A main dealer will likely have no idea about these cars, most of the folks who work on them at main dealers weren't even about when they stopped production  

You may need to have it transported to a specialist at this point. Unless you have a very talented auto electrican locally (or a mechanic who does old school diagnostics rather than just plug a computer in and assume it will tell them the answer) I'd be quite choosy who works on it next. 

[tayr]

i've got a bunch of spare parts for the GS300, i think i've got an ECU if it comes down to it. Let me know

[Scooter]

I'd take Tayr up on his offer of a ECU. On the Supras they are under the passenger side footwell carpet and these days the ECU's can give issues (if you look at a Toyota diagnostics book/procedure the last thing after everything else has been eliminated, on nearly all issues, is "replace the ECU" )

As other mechanics have had a go, then they've 'likely' checked the regular stuff fuel/ignition, distributor, pump etc etc  so a duff ECU is a possibility.

[J4AVX]

3 hours ago, Probby said:

You're not really looking for the ECU at this point, more concentrating on the connectors on top of the coil plugs themselves and anything back towards the bulkhead of the car. 

A main dealer will likely have no idea about these cars, most of the folks who work on them at main dealers weren't even about when they stopped production  

You may need to have it transported to a specialist at this point. Unless you have a very talented auto electrican locally (or a mechanic who does old school diagnostics rather than just plug a computer in and assume it will tell them the answer) I'd be quite choosy who works on it next. 

Thanks, over the weekend I'll inspect the ECU and connectors, I've just downloaded a massive pdf file 144 pages on all the fault codes and wiring diagram. 

 

Re Lexus technican, that's exactly my problem aswell, they won't have a clue given the generation the car is from!

Agree, next electrician I need to make sure he knows what he is doing, already spent £600 with no results!

Thanks for your reply and advice

[J4AVX]

2 hours ago, tayr said:

i've got a bunch of spare parts for the GS300, i think i've got an ECU if it comes down to it. Let me know

Thanks, that might be my next option by the sounds of advice I am getting.

If I replace ECU is it a simple plug and play or does it need reprogramming?

Can you let me know your price for ECU? You can DM (apologies if I am going against forum rules, happy to be corrected on rules!)

[Swampy442]

So you took the engine out of a GS, what engine loom did you use? They arent the same as a Supra, many, many questions

[J4AVX]

1 hour ago, Swampy442 said:

So you took the engine out of a GS, what engine loom did you use? They arent the same as a Supra, many, many questions

The car isn't a Supra..its a Lexus GS300 1996 but the engine is the same one used in the Supra 2JZ GE. its a factory Lexus, the shared the same engine. 

[Swampy442]

Ah right sorry, my bad. Start with the basics first, do you have fuel and a spark. Id say possibly fuel pump but again, could be many different things

[J4AVX]

On 12/2/2023 at 7:07 PM, Scooter said:

Does it start everytime for a short time, or just once then won't start?

You can try starting it without the aux belt on (only for a minute or so)

You could try bridging the terminals in the diagnostics port, the ones that run the fuel pump, then you could try it (again only for long enough to test if that's made a difference) If you bridge the right terminals you'll here the fuel moving when turning on the ignition. 

These are things that might rule things in/out. Chris Wilson on here would say the mechanics need to be more old school and have scopes etc to tell precisely what's going on.

Have you done the procedure to get any engine codes?

 

I have the error code that came up on the diagnostic - its coming up as 14 - Ignition no 1 signal.

Any ideas? 

[Scooter]

From the era, but LS400 specific, I'll try and dig out the non turbo supra diagnostics for 14.

https://www.clublexus.com/forums/ls-1st-and-2nd-gen-1990-2000/456163-code-14-a.html

As other mechanics have looked at it and you've replaced a fair few parts there is a chance it's the ECU per this last comment.

"There are some tests to do to backprobe the igniter and look through a labscope to see a sawtooth, but let's be honest here...you don't have such toys. It can be the igniter #1, the harness to it, the ground, or the computer itself has lost its ability to push out a 5v reference signal (not likely.)

 

[Scooter]

If you want to keep the car for a while this Ebay package might be worth getting?   1993-97 GS300

https://www.ebay.co.uk/itm/284287511697?hash=item4230db2c91:g:-l0AAOSwBtJglpEc&amdata=enc%3AAQAIAAAA4LTswHS%2FIofD%2BtPsRtSFPMC83NP8ym9B83%2B7bhSE9eZVxYtxHKUP1Jb%2BowkCF4wjDiTeStEBNloBvo6NnunDQmaEjP3MRYxhMQLXPkmWFo4ES9pMm%2BTClKxxQElJLwBSmydFnb44qoSwV9pINugi0A4mO4lRYZxQVYWsaP1t43sAKkKnBcriLM4jlA4WwhXNtDFNgufQzU2iA%2BwdfF3KCM4nV8jtptZI4ff21eMTNEeZPRRt1qw5K4gqe8yYKyp0m7KOhbbXSeeCj3hr7cIMX4zx%2FVpbk5EkEyr6FyHah0E%2F|tkp%3ABk9SR-DXof-HYw

[J4AVX]

1 hour ago, Scooter said:

If you want to keep the car for a while this Ebay package might be worth getting?   1993-97 GS300

https://www.ebay.co.uk/itm/284287511697?hash=item4230db2c91:g:-l0AAOSwBtJglpEc&amdata=enc%3AAQAIAAAA4LTswHS%2FIofD%2BtPsRtSFPMC83NP8ym9B83%2B7bhSE9eZVxYtxHKUP1Jb%2BowkCF4wjDiTeStEBNloBvo6NnunDQmaEjP3MRYxhMQLXPkmWFo4ES9pMm%2BTClKxxQElJLwBSmydFnb44qoSwV9pINugi0A4mO4lRYZxQVYWsaP1t43sAKkKnBcriLM4jlA4WwhXNtDFNgufQzU2iA%2BwdfF3KCM4nV8jtptZI4ff21eMTNEeZPRRt1qw5K4gqe8yYKyp0m7KOhbbXSeeCj3hr7cIMX4zx%2FVpbk5EkEyr6FyHah0E%2F|tkp%3ABk9SR-DXof-HYw

Yes I've been looking at the same exact one, I've been speaking to the seller over last few days and he's willing to come down to £250 all in. I think it's a good price given ECU alone going for around £150.

Deffo want to keep the car long term.

Do I need to reprogramme the ECU or will it be a plug and play fitting? 

Thanks for the help!!

[Scooter]

The Supra's you can just swap in so I'd imagine the GS is the same, it's a quick job and if it doesn't fix it you at least have a spare.

[J4AVX]

On 12/6/2023 at 7:52 PM, Scooter said:

The Supra's you can just swap in so I'd imagine the GS is the same, it's a quick job and if it doesn't fix it you at least have a spare.

I've purchased an ECU online (the one that was on ebay). Can anyone guide me on how I can replace and check all the connectors to it?

I've checked a Supra 2JZ GE engine diagram and looks like under glove box?

Appreciate any help, I'm going to do a DIY job on the ECU.

[Scooter]

I think it's like the Supra and under the passenger side foot well.

Passenger door trim unclips somehow to allow you to pull the carpet back and then likely a couple of nuts to release the ecu from it's holder. Then on the Supra there is a nut to undo to allow you to tease off the 2/3 connectors to it?

[Swampy442]

Under the carpet, passenger footwell. Has 2 plugs, one with a 10mm bolt securing it to the ECU, Pull the trim piece up holding the carpet down by the door, peel the carpet back and you'll see it

[J4AVX]

Thanks both! I'll give it a go over the weekend, fingers crossed it solves the problem. Will report back here

[J4AVX]

Hi All

Something really odd happened today. I replaced the battery with a brand new one as old battery was completely dead and thought I'd upgrade anyway given it hasn't been replaced in a few years.

I was getting car ready to replace ECU and thought lemme start up with new battery and check battery is all good, guess what! The car cranked over and started up and didn't cut out! Left it running for a while, turned off and tried again and was fine (didn't drive around though as its SORN and no MOT.

So my question is (and I refuse to believe this!) could it have actually been a battery issue all along, I still think its very unlikely...

Or

The ECU still probs faulty and just luck that it cranked and started without cutting up

Prior to this, the cars been sitting for around 8 weeks and that was the last time I tried starting but would cut out straight anway.

So shall I still go ahead and replace ECU or leave as is and see if issue comes back?

Car has no MOT etc so I want to get it over to the garage soon to get it done and back on road.

Any advice is appreciated guys.

 

[Swampy442]

Its likely a bad battery wont let it start but personally, I dont think thats the issue, If it was the ECU you'd have a 'hard fault' and it wouldnt start regardless. Id leave that as you know it works for now

But congrats on getting it going