MR2 Turbo Stopped Boosting

[mr299ron]

Driving to the airport earlier this week heading to the Amster of Dam, my car decided to stop boosting halfway along the M25. I went to accelerate and it felt like a mis-fire but quite a brutal misfire in the sense that the car just jolted and I had to back out. I could drive normally without using the turbo to the airport.

Got to the airport and reset the ECU, then a week later I came back fired it up and nursed it home not knowing if it was ok or not. Just now, I went for a drive and it was fine. Boosts, no mis-firing, absolutely fine. One thing that I had been noticing is that my HT leads (bought from GTS Chris) keep popping off either after a little while or flooring it in first, so I'm not quite sure if maybe one of the HT leads caused this issue by not being properly seated, as this is what I also did before leaving for Dam alongside the ECU reset.

My lambda sensor has been unplugged for a little while and has been burning on the downpipe. I feel like since the car gets quite hot sitting on the M3 at 77mph and that it went into some sort of limp mode? The ECU reset as far as I'm aware has solved it for now. At least I know the turbo didn't die.

It's not fuel cut either if you're wondering.

Anyone experienced this before?

Cheers
99ron

[Odin_S]

Why keep boosting or using WOT when the problem hasn't been fixed? Do you want to break your car The mind boggles with some owners, issues don't fixed themselves ever I've learnt much less with an ECU reset.

Start with your ignition, I'd change your leads for OEM if possible they pay for themselves over time. I've had mine for 5 years and no pop off or issues.

Stop boosting until the problem is fixed, the car is doing it's best to warn and save you...

[mr299ron]

Odin, thanks for your concern and your helpful advice. However, I hadn't been WOT'ing and/or boosting above 5psi. Just boosting it to 5psi is enough for me to see it as an improvement from before. I'll be nursing it until I can take it to the garage.

My ignition is basically brand new. Bought the car in september and have changed everything bar the coil pack. The HT leads I think do need swapping out, however they're pretty new and they're not cheap. GTSChris sold me them and then went out of business, so I couldn't send them back. xxxxxx.

Regarding the coil pack, I've read somewhere they crack, let water in, freeze and cause issues.

Do you have any idea besides the ignition what it could be?

[androo007]

Dude why the hell are you driving with the lambda sensor unplugged

[mr299ron]

I found it unplugged after it had been into the garage, and it was too late to plug it back in as the connector had melted thanks to the downpipe.

Jesus, do I need to explain myself to all of you keyboard warriors. Don't comment at all if you're going to be unhelpful.

[robbie_742003]

If I was you mate, I'd have took a photo and took it back to said garage and demanded they replace your lambda sensor. All sorts of untold probs with it unplugged.
Get yourself a replacement asap and plug it in.

[mr299ron]

I would do at any normal garage, but it used to be an MR2/Celica specialist and I feel like they wouldn't have done that. He also mentioned the lambda sensor unplugged on the earlier rev1 and 2s don't effect it. I'll replace it anyway.

[androo007]

It's not being a keyboard warrior it's when idiots ask stupid questions it provokes obvious replies.

If you're driving with the sensor unplugged it'll run like sh!t.

[mr299ron]

It's not running like xxxx, and I've been told different information regarding leaving it unplugged on the rev 1 and 2s. The garage I went to is a Celica/MR2 specialist, so I'm questioning what they've said on here to see what you keyboard warriors have to say. Idiots make assumptions and comment stupid things. Don't be a moron andro.

You lot are worse than MX5nutz.

[ashley]

Now now children, play nice!

[Nic]

Have you checked the ECU for fault codes?

[gnzyza]

These cars have one right, at the top manifold.
Is it that one unplugged? I find unusual. You sure its not the car sensor further down?

[androo007]

[JD]

MR2 ECU on all revs does not have a limp mode. GT-Four does. You can check the fault codes using this guide here. As long as you have a paper clip it's dead easy. Remember to reset ECU before you check again.

The advice from the thread suggests that you rewire the sensor and plug it back in. I personally see no keyboard warriors

[mr299ron]

What about the Mine's ECU? Just found out I have one on the car, which is surprising. Looking online, they're just a stock ECU with a remapped ROM chip that uses stage 1 mods more efficiently, raises RPM, advances timing, and runs more aggressive fueling.

Since the ECU is different to the stock ECU, and I'm running more mods/boost/power, wouldn't I need something like the lambda sensor to help with the fueling since I'm using more?


Would it be possible to buy an OBD diagnostics kit to plug into the ECU and my laptop? I can't check for codes using the standard way, as my EML light doesn't turn on but the bulb checks out to be ok...

[gnzyza]

You definitely should be running 02 sensor, I think its already been mentioned

[Odin_S]

If i were you mr299ron, i would sit down and study the SW20 and more importantly, the car you have. I would have assumed you did this before you decided to buy an MR2.

I just see you heading for a broken engine

To answer your question, your ECU cannot be reprogrammed just like the standard ECU cannot, OBD1 only came in on the very last JDM Rev 5 N/A
no turbos from factory

[mr299ron]

I've been told by an MR2 specialist that the lambda sensor is not a necessity for the earlier models. I've been told by you lot I need it, I've seen elsewhere you don't. I understand how a lambda sensor works, and I'm pretty sure I would bloody need one, but why would someone say you wouldn't!! This is what the forums are for. Asking lots of stupid and random questions to get your answer. How else do you learn? Waiting for it to blow up..

[Nic]

The MINE's ECU *may* have a built in limp home mode (which could be what you experienced) and *may* also be why the master warning light isn't working. If you email MINE's with the details from the ECU, they will tell you the spec and they'll be able to tell you if it does have a limp home mode function.

http://www.mines-wave.com/E_09/Inquiry_E.html#Q3

Q3) I have a Mine's VX-ROM. And the plaque has a serial number on it. Can you tell me its tuning contents through this number?

A3) We can not tell you its tuning specs only by this serial number. If you give us its numbers and letters on either side of VX-ROM through e-mail with attached photos, we could give you some information such as its maximum boost pressure, Speed Limiter, vehicle year and etc...
If you are in Japan and send us your VX-ROM, we can check it, confirm its tuning specs, and send it back to your own expense.

You need to get the stock O2 sensor connected and if the plug leads are loose then I'd replace them with new OEM or Denso ones. I would also try to borrow/buy a stock ECU to test the car with, you can then check if the warning light works and if it stores any fault codes.

[mr299ron]

Boom! The answer I was looking for. Thanks Nic.

I have already E-mailed them about the ECU, but haven't asked anything about limp mode. Will be sure to ask them. Thanks a lot.

I'm using another car for the moment, so will stay off the road until I get that sorted. The plug leads are funny, they sometimes pop off. Mainly the far right one when standing behind the car. They don't disconnect, just pop off.