Thread: ZD30 engines

Originally Posted by justinc

I am in agreeance on the electronics point. The cylinder head and pistons etc are not much different in complexity to a Td5, yet seldom do I see a Td5 around 650 to 700 degrees EGT.

I think that if I was able to trick the MAF into reducing fuelling slightly, rather like a reverse of the power upgrade chip interrupter, then it might help these engines last longer. They have impressive power output for a 3litre motor, I would reduce the power slightly if it meant longevity...
Any electronics guru's care to help design a 'less power box' for these vehicles?
We could potentially sell thousands
JC

Justin, the main issue with these engines and why you are seeing high EGT values comes essentially from the MAF incorrect readings back to the ECU. As the ECU also controls the wastegate, this leaves the turbo to overspool resulting in it spinning well into max choking limit and increasing intake temps and combustion temps. As the intercoolers on these are small to say the least, efficiency drops dramatically.
Being a VNT style turbo, this accentuates the low speed boost and kind of makes it get to a high state a bit quicker than normal.
I would suggest fitting a temporary boost guage and correlate the EGT and boost over a load and rev range and see what comes of it.
Why it cannot default to a safe mode is anyones guess.

Not sure if there have been issues with engines fitted with a Dtronic or similar, but would be interesting to find out.

Originally Posted by LOVEMYRANGIE

Justin, the main issue with these engines and why you are seeing high EGT values comes essentially from the MAF incorrect readings back to the ECU. As the ECU also controls the wastegate, this leaves the turbo to overspool resulting in it spinning well into max choking limit and increasing intake temps and combustion temps. As the intercoolers on these are small to say the least, efficiency drops dramatically.
Being a VNT style turbo, this accentuates the low speed boost and kind of makes it get to a high state a bit quicker than normal.
I would suggest fitting a temporary boost guage and correlate the EGT and boost over a load and rev range and see what comes of it.
Why it cannot default to a safe mode is anyones guess.

Not sure if there have been issues with engines fitted with a Dtronic or similar, but would be interesting to find out.

I was suspicious of the MAF in my nissan shopping basket, so I was able to find a FSM on the net which detailed the simple tests to check for correct operation.

It was as simple as sticking a multimeter on the correct wire (there are 5, it's obvious when you've got the wrong one), read the volts at warm idle and again at 2000rpm with no load.

To get a good voltage reading without stripping the wires, I just poke a pin into the connector alongside the wire, hook my multimeter jumper wires onto it.
In my case the values came out perfect. One of the reading was supposed to be in the range 0.7-1.1 volts, it was 0.9 volts. The other was also smack in the middle of the intended range.

Easy to check and worth doing if you can find the reference figures.

I think it's funny that an LR mechanic is sorting out a Nissan problem.Good your here JC. Pat

Originally Posted by LOVEMYRANGIE

Justin, the main issue with these engines and why you are seeing high EGT values comes essentially from the MAF incorrect readings back to the ECU. As the ECU also controls the wastegate, this leaves the turbo to overspool resulting in it spinning well into max choking limit and increasing intake temps and combustion temps. As the intercoolers on these are small to say the least, efficiency drops dramatically.
Being a VNT style turbo, this accentuates the low speed boost and kind of makes it get to a high state a bit quicker than normal.
I would suggest fitting a temporary boost guage and correlate the EGT and boost over a load and rev range and see what comes of it.
Why it cannot default to a safe mode is anyones guess.

Not sure if there have been issues with engines fitted with a Dtronic or similar, but would be interesting to find out.

So is that the key? The wastgate is electronically controlled on the nissans? So if the MAF doesn't work it overboosts? The wastegate on the TD5 is not electronically controlled, right?

I recon your right. Pat

Originally Posted by Pedro_The_Swift

show these please.

If you search the forum, you will find plenty of people talking about it. The survey one is here..

Nissan Zd30 Survey Please Read - Patrol 4x4 - Nissan Patrol Forum

Here is the link to the survey on Patrol4x4

Nissan Zd30 Survey Please Read - Patrol 4x4 - Nissan Patrol Forum

If you search teh site there are plenty of people talking abotu them. Also there are a few threads about cleaning the MAF sensor and the results.

Originally Posted by Captain_Rightfoot

So is that the key? The wastgate is electronically controlled on the nissans? So if the MAF doesn't work it overboosts? The wastegate on the TD5 is not electronically controlled, right?

I think it is, turbo boost on TD5s is controlled by the ECU, if the ECU detects over boost it will put the car into limp until it drops, to increase boost in TD5s there is a box that can fool the ECU into thinking the boost is normal.

So if this is the case would that mean the wastegate is electronicly controlled??

Baz.