Basically we have a UK version of the 2+2 twin turbo.

At the moment its failing to start.

My friend informs me hes checked over the injection system and the timing ect and all is fine. The engine turns over fine without actually firing. But were sure theres a spark which may sound stupid. You can hear the exaust popping when trying to turn it over but it just wont go. :(

 

Were thinking something electrical is the culprit as oppose to the engine repair work thats been carried out.

Now we found the ecu from underneath the passenger footwell. as some how were getting a flash cose which i think = 34 . Which points to the deternation sensor we think.

 

My questions are. would this stop it starting. and if theres other faults would it flash up the codes one after another ' or wont it flash the code until we have fixed the first problem? Also when the ignition is turned on the engine check light does not go out! which i presume indicates theres a fault hence when i set the ecu to its diagnostic mode it flashes out this code??

The ecu has 1 single red light that flashes at different rates. the longer being the 10s i presume and the shorter flashes meaning the end number.

 

 

Anyhow any help on this subject would be very much apreciated. heres a pic of the engine we are working on below!

Code 34 is indeed Det sensor, it wont prevent it from starting, will only put it in safety mode (reduces boost, retards timing slightly).

 

Im unsure if the ECU will give a series of Fault codes or if its only one at a time.

 

You can try bypassing the Det sensor for now, by using a 1 Meghm resistor at the Det sensor connector (see http://zhome.com/ZCMnL/PICS/detonationSensor/detonationSensor.html)

 

It could be the PTU (Power Transistor Unit), its job is to amplify the ignition signals from the ECU to each of the individual coilpacks on the Spark plugs, and is a common failure in Series 1 zed's.

 

The Coilpack connectors can also be a weak point themselves , taking abuse from the engine bay heat.

 

Have you removed each spark plug and tested for sparks when turning ignition ?

 

The best 300zx Experts in the country frequent this forum, so Im sure somebody with more technical expertise will have some definate answers for you.

check here for retreiving codes, if there is more than 1 code then it will cycle through them.

 

& no, a det sensor failure will not prevent it from starting

Ok heres the current state of play.

 

Re wired the det sensor and now have no fault code for it.

Tested the ecu by pulling some other sensors of the bay and got the required fault codes. Now we have the ecu showing code 55 which is all clear.

 

But we still have no start. Engine cranks over but dosent want to fire.

All the plugs have been checked for spark and they all seem fine. Fueling seems fine as we ran our own electric pump out of a barrel of petrol.

 

What we do get is alot of popping and crackleing down the exaust when its cranking over. Which we cant understand. And the engine check light still stays on solid (it may well do but i presume it should go out? )

 

Anyhow anyone have any good ideas>? What more would having her plugged in show than what the ecu fault codes show? The only thing we are checking is the ptu unit. we are thinking it might not be giving a strong enough spark perhaps? hence it wouldnt show a fault to the ecu but it might not be giving a strong enough signal for the coil packs??? just a thought

 

anyhow answers on a postcard please lol

 

Cheeers

Chris (on behalf of phil)

Where are you, maybe a member near you might swap their PTU over for testing?

 

Vijay

im in walsall just outside of birmingham.

Would be handy if that could happen.

:smash: