ECU replacement cost

[MartinW]

Has anyone here had to have their ECU replaced or know how much it costs?

 

I've got the high rev (when idling) issue and so far the usual pedal dance etc hasn't worked. I'm getting it looked at properly next week but I'd like to have any idea of costs in the worst case scenario.

[Flashback]

Basic costs look to be something like £50-£75 for a second hand one: https://www.ebay.co.uk/b/Nissan-350-Z-Car-ECUs-Computers/61525/bn_1259493

 

I think you then need to get it coded to your car by a specialist that knows what they are up to and possibly mapped as well.  Some of the traders on here could probably give you some better advice if you need to do it.

[KyleR]

Probably nothing to do with the ECU. Inspect your air filter and MAF first. Even if it turn our to be an ECU issue, a remap would most likely sort it.

[MartinW]

Cheers Kyle.

Last week I cleaned the air flow sensors and sprayed some egr cleaner up through the rubber tubes to the throttle bodies while the engine was running but it made no difference.

I took a closer look at the throttle bodies today without removing them and have them a clean as best as I could with a clean cloth and it actually seems like it's helped a little.

It's going to the garage on Tuesday so I will get them to try a full thorough clean as the first thing before they start dismantling the engine any further.

 

Curious about the throttle body... How stiff are the butterflies to move normally? 

Should you be be able push them both ways or do they only move in one direction?

 

The car was apparently serviced by the dealer when I bought it... Looking at the air filters, they certainly aren't new, is that something you'd expect to be changed in a standard service?

Got some new ones on order anyway, going for these https://www.tarmacsportz.co.uk/nissan/nissan-350z/cosworth-nissan-350z-07-high-flow-synthetic-air-filter-twin-air-box-type.html

Edited April 7, 2018 by MartinW

[KyleR]

Have you tried all these?

 

https://h-dev.co.uk/350z-reset-proceedure-pedal-dance/?v=79cba1185463

 

I can’t remeber how stiff the butterflies are, it’s a good few years since I last played with them, but I imagine they’ll only turn one way. As for the air filters, they’d be changed as and when required, not every service.

[Jack94]

The butterfly valve only moves one way and you should be able to move it with your fingers, I moved mine all the way when I had it off the car to clean it properly.

If you're gonna  move it whilst it's still on the car then make sure you disconnect the battery, ECU and throttle body first so you don't upset it. 

[MartinW]

Kyle, yup I've tried the pedal dance multiple times ( both before and after cleaning AirAsia flow sensors etc)

 

Thanks for the advice Jack. I'm not going to touch it again for now, will let the mechanic sort it on Tues, the dealer who sold it to me will be paying for the work anyway so might as well let someone more clued up take a look.

[Jack94]

2 hours ago, MartinW said:

Thanks for the advice Jack. I'm not going to touch it again for now, will let the mechanic sort it on Tues, the dealer who sold it to me will be paying for the work anyway so might as well let someone more clued up take a look.

 

No worries mate fingers crossed they can sort it for you, and bonus that you won't be the one paying the bill! 

[MartinW]

My mechanic spent the day on this today, checked for air leaks, cleaned the throttle bodies, ran diagnostics, reset the ECU etc all of which made no difference.

He found 2 air pipes hidden under the engine cover that were disconnected so he reattached them. Now it still idles high and is hunting / fluctuating even more.

 

It looks like the ECU is my last option, having read this https://h-dev.co.uk/2016/08/18/350z-hr-vq35hr-high-idle-fix/?v=79cba1185463

And a bunch of other forums etc out there I think an ECU replacement is the only thing left that will fix this.

[KyleR]

Horsham aren’t far from you, you should give them a call and book it in.

[MartinW]

I spoke to them.

For £500 they can do their "fix" but that leaves the immobiliser disabled and a light on the dash.

My mechanic is getting a quote for an ECU replacement so I should hear about that tomorrow.

The dealer who sold me the car said he would pay for the repair as it's still under warranty, I think my biggest struggle is going to be getting him to agree that spending over £1k for an ECU is the only solution.

[Flashback]

On 10/04/2018 at 20:22, KyleR said:

Horsham aren’t far from you, you should give them a call and book it in.

On 10/04/2018 at 20:35, MartinW said:

I spoke to them.

For £500 they can do their "fix" but that leaves the immobiliser disabled and a light on the dash.

My mechanic is getting a quote for an ECU replacement so I should hear about that tomorrow.

The dealer who sold me the car said he would pay for the repair as it's still under warranty, I think my biggest struggle is going to be getting him to agree that spending over £1k for an ECU is the only solution.

Personally I wouldn't take my zed anywhere other than H-Dev as the guys are excellent.  I'm sure it wouldn't cost £500 to take a look and plug in just to check what they can see...and surely worth a try before chucking a grand at a new ECU.  Jez at Horsham runs an Engine Management school and knows the cars inside out.

 

If not Abbey are also excellent and not too far away.

[MartinW]

6 minutes ago, Flashback said:

Personally I wouldn't take my zed anywhere other than H-Dev as the guys are excellent.  I'm sure it wouldn't cost £500 to take a look and plug in just to check what they can see...and surely worth a try before chucking a grand at a new ECU.  Jez at Horsham runs an Engine Management school and knows the cars inside out.

 

If not Abbey are also excellent and not too far away.

 

It's already been plugged into 2 diagnostics machines, a snap on one and another specialised for Japanese cars but I can't remember what it's called. Both show no faults under normal conditions... Only when air sensors etc get unplugged as you'd expect.

 

I called a local Nissan dealer who weren't familiar with the issue, they would want £70 to run their diagnostics and if it is the ECU they quoted me around £1700 for a replacement.

 

As I've only had the car a few weeks and the dealer has already said he would pay for repairs I have decided that I will let the dealer sort it.

I've told him that it will need to go to a nissan specialist, not his dodgy mate round the corner but it's up to him now. I just can't afford to incur any further costs with either diagnostics or replacing parts trial and error style.

 

Thanks for the advice though, I will update when I've made some progress, I really hope it's sorted in time for Japfest

[Mark@Abbey m/s]

Seen this a few times and we quote the same costs as Horsham. Within the ECU there is 2 Eprom , 1 controls fuel ignition etc the other the idle control and the NATS. The Idle Eprom becomes corrupted resetting this also resets the NATS which cant be re-coded cheaply. So we turn the NATS off with a Uprev reflash.

 

Normally this is caused by the Throttle butter flies being opened manually. We advise this not to be done even with the Battery and Throttle bodies disconnected.  

[MartinW]

Hi Mark.

 

One thing I've been trying to avoid is spending money on unnecessary repairs. While at the moment everything points to it being the ECU I've heard other suggestions such as a faulty lambda sensor, Faulty MAFs or throttle bodies etc... How much work would it take to be able know what the issue is for sure?

 

My concern about the re-flash is that by leaving a light on the dash and disabling the immobiliser it makes the car harder to sell on in the future and would probably affect its value. I would also have to inform my insurance company that it no longer has an immobiliser.

 

The dealer who sold it to me is being very slow about getting it all sorted so I may be able to help influence where it gets taken for its repair, he would need to be confident though that the issue could be diagnosed and repaired for a reasonable price... As it's the dealer paying for it, if it is the ECU I think he should be paying for a complete replacement, is that something you guys would also do?  

 

[Mark@Abbey m/s]

@MartinW  The issue is to keep the NATS other than fitting a new ECU is the get the NATS code from Nissan this will be the problem Nissan never want to give the NATS code out we have found.

 

I can try a good ECU in your car with the NATS turned off to check if the ECU is the issue which I am certain it will be if you have a drive to Abbey. The ECU if you buy from Nissan UK will be a straight fit and go as it will come in its virgin form that will code itself re the NATS once fitted.

[MartinW]

I've finally managed to get the dealer to get this checked out at his cost. I'm stuck driving a rental Corsa at the moment, hopefully he has it sorted in time for Japfest.

His mechanic thought that the issue was the throttle bodies but I still reckon ECU... Will update when we find out for sure, he has said he's booked it into nissan tomorrow so I reckon his own diagnostics showed nothing 

[MartinW]

A big shout out to Mark at Abbey Motorsports. A top bloke who went out of his way to help me out today, we've now figured out for sure that the issue with my car is definitely the ECU.

Next step is to get the dealer to pay for the replacement!

[MartinW]

Looks like I've finally got somewhere with this.

Thanks again to @Mark@Abbey m/s for your help and advice and the @ZMANALEX for supplying a second hand ECU and being patient with my dumb questions.

 

I installed the 2nd hand ECU this morning (which already has an uprev on it) and the problem has gone, it drives so much more smoothly now. The NATs light is on but I think that's pretty normal for an uprev ECU?

Or is it possible to get the code from nissan and have both the uprev and the NATs coded in?

 

It was a bit of a kerfuffle getting the ECU swapped over

 

 

 

But now it idles normally

 

And I could finally put my new mats in

 

[wizard]

Ah great job.

In future if anyone has an issue like this, I have a few Nissan ECU's which you can try out for free.

Great job Martin, look forward to seeing a turbo on this one too