2003 dx miss firing

[KNIBBS]

Hi Guys

I decided to start a new post as i found more problems. Took it to my mechanic to go through it. have to give a shout out to promnt Auto repairs in Darwin. they spent an hour on it and didn't charge me.

So problems
-Miss firing at high revs
- loss of power and fuel eccom
- late boosting
- egr faulting
- whistle at high revs

My mechanic doesn't want to just replace the EGR as he wants to investigate what else may be coursing the problem. the Turbo has been tested and is fine. no leaks in the intake. He said he had the same problem on another ZD30 and replaced turbo and EGR and it didn't fix the problems.

Firstly what should i expect to pay to replace the EGR or can i do this myslef ? and any ideas on what could be cuasing the miss firing ?

I am planning on checking,
- small vacuum lines to the turbo and its connected control solenoid on the bulkhead,
-glow-plug relay is switching off
-injector nozzle
-high pressure hoses post turbo/s for any split hoses or cracked metal pipes
-airflow meter
-throttle pedal sensor
-compression test

Anything i missed ?

 

[4x4 ST-R]

You mentioned injectors, that's one thing I would have said. What ever it is, let us know. Your probably not the first, and won't be the last with this problem.

And if the turbo has been given the all clear you will most likely find a split in one if the lines. That will cause you to lose heaps of power. On Sunday I was powering up a big long hill in 5th, I had heaps of boost, good revs, and then all of a sudden I lost all of my boost pressure and engine power.

Pulled over and saw the boost pressure line for the boost gauge had popped off. Reattached it and it was good to go again. So with a split it could be doing a similar thing.

 

[KNIBBS]

It's not a intake hose as i had the miss firing problem before i losy power. i noticed a small split in one of the smaller hoses but it is not sucking through. i still have heaps of boost power. has me and my mechanic stumped.

 

[Pinelli]

Whistle at high revs? Leak in the exhaust manifold? Not sure if it would cause misfire, but could cause power loss at high revs, as you won't be getting the air flow that you need.

BTW, might do better posting in the D22 section

 

[Old.Tony]

A whistle at high revs could be the turbo whine, or it could be boost leaking out of a joint. Hard to spot, but you could look for signs of oil coming from the intake lines - if your PCV is connected to your intake, your intake post-turbo will be covered in oil on the inside. A leak will push this out.

Misfiring is due to a few things: bad timing being the first possibly culprit, might be a slightly maladjusted CAS. It's also possible that there's not enough fuel getting there - do you have two fuel filters? How long since they were changed?

You could also try loosening the fuel cap. If the tank vent is blocked, it could create a vacuum in the tank inhibiting flow which is especially important at high revs.

I assume your air filter is clean and other hoses have been checked for cracks and blockages?

 

[KNIBBS]

A whistle at high revs could be the turbo whine, or it could be boost leaking out of a joint. Hard to spot, but you could look for signs of oil coming from the intake lines - if your PCV is connected to your intake, your intake post-turbo will be covered in oil on the inside. A leak will push this out.

Misfiring is due to a few things: bad timing being the first possibly culprit, might be a slightly maladjusted CAS. It's also possible that there's not enough fuel getting there - do you have two fuel filters? How long since they were changed?

You could also try loosening the fuel cap. If the tank vent is blocked, it could create a vacuum in the tank inhibiting flow which is especially important at high revs.

I assume your air filter is clean and other hoses have been checked for cracks and blockages?

Sorry for the late response

All filters were changed 2000km ago, had a major service done and changed every fluid possable. i just got the turbo checked and it is in perfect working order. waiting for my mechanica to come back to me, he is getting some advise from a nissan engineer

 

[Dave]

EGR pipe around the firewall, check its still in 1 piece ?

Silicon hose fine ?

Check the Neutral position switch for the down on power bit.

Why is this in the D21 section ?

 

[Dave]

Tired response.

 

[KNIBBS]

Soory guys haven't had time to check, checked all hoses and pipes they seem fine, egr is still not replaced. Waiting for my mechanic to come back to me. I will advise how i go.