Emmisions problems

[costaricanzuu]

Hi guys I'm having some problems with my 2.5 turbo 4JA1-T, here in Costa Rica we have anual emmisions tests (the limit is 2.80m-1) 2 years ago my reading was 0.90 so it was pretty great, last year it made a huge change and climb to 9.90 it didnt pass, so I take it to a diesel shop they told me that my injectors were shot but they do something to it so I pass with 2.28 barely did it, but It has no pulling power It was scary slow and powerless so I open the injection pump and it was "fine".... yesterday I took the test again I close the pump before the test, and well it didnt pass againg 8.87.

I know that I have to change my Injectors but right now I can't afford it Its like 100 american dollars per injectors plus the diesel shop charge....,
But what really bothers me it's why the emmision went up that fast 9 point in one year, does the injectors die so fast??
It's anything else that can make my motor trow that high number? could the EGR be bad or something?

for the record
I got good fuel economy like 11km per liter
It doesnt burn a drop of oil
It starts great at cold morning at the first try

Thanks a lot for your help and your time for reading !
I'm kind of frustaded right now speccialy because of the change on the emmisions numbers

[geeves]

could be the EGR but Im sure the diesel shop would of checked this. Most diesel engine suppliers say new injectors every 100000km but more often if low fuel quality. What mileage have you done? Over here we have a process called carbon clean which is really a monster dose of injector cleaner in a controlled manner that can help a lot of engines but not all.
You could always adjust to pass then adjust back to drive home

[costaricanzuu]

mmm... I'm at 191000km, someone told me to try Biodiesel it's supposed to drop down the emmisions but Im not sure if that can help me.

What kind of injector cleaner could I use the cheap ones like STP or Gunk or theres something better?

Im not really happy with the shop that do the job, how can I checked the EGR system?

Thanks a lot Geeves! I love my Isuzu and really want to keep it running good!

[geeves]

Is that measurement Carbon monoxide , hydrocarbon or nitrous oxide?
Unless your nitrous is low its better not to play with the EGR although when it fails engines run terribly.
Since they are going to look for modified emissions gear I would undo the 2 egr valves and make a solid gasket to go over the holes in the inlet manifold then bolt the valves back on. Best to use a high temperature gasket paper or 0.5mm aluminium. This will disable the EGR and not be visable to the emissions police. It would be interesting to know the result.
Biodiesel might drop emissions but there are several things called biodiesel.
The injector cleaner I use is a Nulon product but I only have to pass a visable smoke test

[costaricanzuu]

I was reading a little bit more today, the test it's called OPACITY, what they measure its percentage of light passing though the smoke, so they push it to 4500 rpm and a amachine reads this, my ute smokes a lot during the test...
sooo I'm stuck to changing the injectors?
could the timing of the injection pump put more smoke out?

[Blondini]

I would be going of my nut if they take my motor up to 4500rpm that red lines at 4000 .
Any diesel would smoke at that revs. 3500 Max

[geeves]

They are doing the test with a fully warmed up motor arnt they?
Running the engine on the rev limiter is going to give bad results every time. I would question the validity of that test on a diesel with your diesel mechanic, the mechanic doing the test and your transport agency

[Yarno]

Make sure the air filter is fresh, and maybe pull the boost compensator line off the pump to stop it pumping in extra fuel. Might work...

[geeves]

free reving there wont be much boost but it might be just enough

[costaricanzuu]

thanks a lot!
I'm going to change my filters and add some cleaner and see what its going to happend because right now I cant afford the new injectors =(

[pig75]

You could just wind the pump back in for the test

[costaricanzuu]

Well guys today I decide that it was time to pass my emmision test( actually I cant wait more for law!) so I put a bottle of injector cleaner in like 1/4 of tank, and add a bottle of 1 liter of soy oil (cooking oil), drive it hard for like 4 km in the highway and decide it was time to do the test I went to the station and.... I passs!!! wohoooo!! =)
my number change from 8.87 to 1.91 been 2.80 my limit so I'm done until next year!
Maybe it will sound weird but my car now feels a lot smoother and quieter I'm guessing that my injectors are a lot cleaner than yesterday!

Thanks a lot for your comments and help!!! you're awesome!

[geeves]

Why soy oil?

[wbski007]

The soy oil is probably whats quieting your engine down, I've noticed all the diesels I've run the vegetable oil in run quieter, I think explosion in the cylinder is'nt as powerful as diesel, as I have also noticed a reduction in power when running veggy oil

[costaricanzuu]

Why soy oil?

hahaha for nothing special it was in my house so I stole it! after the test I add more diesel and it keep smother than before, last year when I took the car to the diesel shop the owner told me that he add some cooking oil from time to time in a way of mantenance because its like a cleaner/lubrication help, I'm not sure about it but at leat I pass the test Im planning on taking it to the shop in the next 6 monts to change injectors and adjust everything related to the injection system.