R34 GTT won’t start

[Bigpad]

Hi Guys,

my car issues seem to be going from bad to worse and I’m hoping someone can offer some advice. I’m a Brit and have asked for help on the Brit forums but they’re not as active as they once were. 
 

To save my thumbs I’m just going to copy and paste my posts from the Brit forum. I hope this isn’t considered lazy or rude:-

1st post…… For a while now my dash warning lights on my R34 GTT have been coming on. All of the them. When it happens the car runs like a bag of s**t. I pull over. Turn the car off and back on and the problem goes away. It doesn’t happen again for ages and then all of a sudden the dash lights up and the car is struggling. This has become more and more frequent and it’s now pretty much undrivable. I need to sort this out but don’t know where to start looking. A quick search around the forums and I’m thinking maybe coil packs but I don’t want to just change parts for the hell of it.

2nd post…… Ok the latest in the saga…….
I decided to replace the spark plugs and coil packs to eliminate them as the problem. I figured they were over 20 years old and could do with being replaced anyway. I’ve just been out to have a go at changing them but the car won’t start. It turns over fine but won’t fire. I had a replacement CAS here so have swapped that out but it still won’t fire. Pretty sure I’m getting fuel to the injectors as I can smell it! Any ideas?
Should the coil pack harness have a constant 12v feed once the ignition is on? Can I test this just by putting a meter across the + and ground pins? Is there a relay or something that should give the harness power once the ignition is on?
Any ideas/advice would be appreciated. I’m at my wits end.

Don’t know where to start looking really???

[Duncan]

Are you sure you have the right spark plugs and coil packs? Since they are the thing you changed immediately before it wouldn't start. Also, depending what you unplugged, make sure everything is seated properly and any grounds were bolted back down again too.

I'm not certain about the 34 gtt setup, but assuming it is the same as earlier models you should find a pair of relays at the passenger kick panel, one for the ECU and one for the ignitiion. You should hear/feel them both click when the key is turned to ignition, and off again when the key is turned back to ACC (the ignition relay turns off immediately, the ECU relay turns off after a couple of second)

[Bigpad]

Thx for the reply Duncan. I didn’t explain myself properly. I didn’t actually get around to changing the plugs and packs. Tried to start the car to pull it onto my driveway and it wouldn’t start. Baffling. Will have a look for those relays when the sun comes up. Thx again. 

[Duncan]

In that case, your whole issue could just be fouled plugs. I'd pull and replace them before worrying about anything else

[Bigpad]

So….. I’ve replaced all the coils and made sure I have a spark by fitting a spark plug to one of the new coils and cranking the engine. I’ve ensured I have fuel by removing what I assume is the ‘return to tank’ fuel line and cranking the engine. So I have a spark and fuel and the car still won’t run. Any ideas?

may be time to get an auto electrician out! 

[Bigpad]

Oh. One thing I did notice while the car was in bits was that the throttle butterfly was fully open. I thought this was odd. Surely with no foot on the gas pedal the throttle should be fully closed? Or is this normal?

[Ben C34]

On 1/23/2022 at 5:11 AM, Bigpad said:

Oh. One thing I did notice while the car was in bits was that the throttle butterfly was fully open. I thought this was odd. Surely with no foot on the gas pedal the throttle should be fully closed? Or is this normal?

That's the traction control throttle body,  the one with the cable is the actual throttle body.

 

 

 

[joshuaho96]

What does the ECU say? Does it get an RPM signal? Is it receiving the starter signal? Does it see acceptable battery voltage? Does it report any codes? Don't parts cannon a no-start condition, engine not starting is a pretty simple issue to debug. Either it's fuel, spark, or you have a mechanical issue causing excessively low compression.

[Bigpad]

On 23/1/2022 at 3:58 AM, joshuaho96 said:

What does the ECU say? Does it get an RPM signal? Is it receiving the starter signal? Does it see acceptable battery voltage? Does it report any codes? Don't parts cannon a no-start condition, engine not starting is a pretty simple issue to debug. Either it's fuel, spark, or you have a mechanical issue causing excessively low compression.

How do I know what the ecu is saying? Is there a diagnosis I should be doing? 
thanks for your comment. 👍

[Bigpad]

Ok I have it running. I did the plugs and coils and it ran. It ran like a bag of shit but it ran. Disconnected the MAF and it ran much better. Plugged the MAF back in and it ran like shit before cutting out. I think I have my problem. I will source a replacement and post the results. 

Thank you all for your help so far. 

[joshuaho96]

On 1/23/2022 at 4:08 AM, Bigpad said:

How do I know what the ecu is saying? Is there a diagnosis I should be doing? 
thanks for your comment. 👍

It sounds like you figured it out but for future reference a Consult cable + Nissan Datascan 1 will be able to read out all of the data from the stock ECU or a chipped/Nistune variant of it.

[GoHashiriya]

On 1/24/2022 at 1:39 AM, Bigpad said:

Ok I have it running. I did the plugs and coils and it ran. It ran like a bag of shit but it ran. Disconnected the MAF and it ran much better. Plugged the MAF back in and it ran like shit before cutting out. I think I have my problem. I will source a replacement and post the results. 

Thank you all for your help so far. 

If it is the MAF, have a look into resoldering the joints in the MAF - it's a super easy process and would be a quick/cheap fix if that's the source of your issues.

On 1/24/2022 at 9:26 AM, joshuaho96 said:

It sounds like you figured it out but for future reference a Consult cable + Nissan Datascan 1 will be able to read out all of the data from the stock ECU or a chipped/Nistune variant of it.

+1 get Nissan Datascan, it's about 30 bucks online. You'll need a consult cable - I just bought a China one from the Japanese ebay equivalent.

[Bigpad]

Definitely going to buy one of those data scan thingies. Thx guys. 

[Bigpad]

Well I bought a pink label MAF off a low mileage r33 spec 2. I’m told they’re the same? Plugged it in and started the car. It fired and ran just fine (I didn’t take it for a spin as it’s cold and dark and I haven’t done up all of the hose clamps or brackets). 
However, despite the car seemingly running fine all of the dash lights are still lit up. I won’t know how she runs for sure until the weekend but I’d really like to get those dash lights sorted? Any help or advice would be appreciated! 👍

 

Also….. Is this what I need:-

 
and then download the data scan 1 software?

thanks again. 👊

[joshuaho96]

On 1/25/2022 at 11:03 AM, Bigpad said:

Well I bought a pink label MAF off a low mileage r33 spec 2. I’m told they’re the same? Plugged it in and started the car. It fired and ran just fine (I didn’t take it for a spin as it’s cold and dark and I haven’t done up all of the hose clamps or brackets). 
However, despite the car seemingly running fine all of the dash lights are still lit up. I won’t know how she runs for sure until the weekend but I’d really like to get those dash lights sorted? Any help or advice would be appreciated! 👍

 

Also….. Is this what I need:-

 
and then download the data scan 1 software?

thanks again. 👊

https://nisscan.com/NDSI/index.php?content=supportedadaptors
 

Looks like it’s the right one but not sure.

[GoHashiriya]

On 1/26/2022 at 4:03 AM, Bigpad said:

Well I bought a pink label MAF off a low mileage r33 spec 2. I’m told they’re the same? Plugged it in and started the car. It fired and ran just fine (I didn’t take it for a spin as it’s cold and dark and I haven’t done up all of the hose clamps or brackets). 
However, despite the car seemingly running fine all of the dash lights are still lit up. I won’t know how she runs for sure until the weekend but I’d really like to get those dash lights sorted? Any help or advice would be appreciated! 👍

Also….. Is this what I need:-

 and then download the data scan 1 software?

thanks again. 👊

it will help if you have the software. I can't remember what happened everytime my car has thrown a code as I would usually just investigate, then fix, then remove the error with Nisdatascan.

That cable should work. The one I bought was just a random Chinese one (probs the same as that) which had no mention of compatibility with Nisdatascan.

You should note that there is some weird (USB) port thing with the adaptors and the software where it won't connect unless it's in the right USB port - you can google around to find the issue. I could only get the the adaptor to work on one of the USB ports on one laptop, irritatingly it's my largest laptop.

[Bigpad]

Ok thanks. I don’t have a tonne of laptops to choose from so wish me luck. Will take a lifetime to get here from China anyway. I can live with the dash lights until then as long as the car drives alright. Will find out soon enough I suppose. 
👍👍

[joshuaho96]

On 1/26/2022 at 12:44 PM, Bigpad said:

Ok thanks. I don’t have a tonne of laptops to choose from so wish me luck. Will take a lifetime to get here from China anyway. I can live with the dash lights until then as long as the car drives alright. Will find out soon enough I suppose. 
👍👍

You can check for codes in the meantime with a jumper wire.

[Bigpad]

Ok. Any advice on this? Wouldn’t know where to start. I will take a look around the forum. 
thanks. 

[joshuaho96]

On 1/26/2022 at 10:14 PM, Bigpad said:

Ok. Any advice on this? Wouldn’t know where to start. I will take a look around the forum. 
thanks. 

https://www.importavehicle.com/blog/check-engine-light-diagnostic-trouble-codes-for-1989-to-1994-nissan-skyline-gt-r