Diesel Fuel Injection System Help Desk

[maedz]

Sir Dieseldude,

Is there any difference with the denso and zexel noozle tips? for example my original is zexel 121 and i'll change it to denso 121... is it just the same or there is still slight difference even though they have the same number? tnx a lot and God bless.

[Dieseldude]

sir dieseldue,

Big tnx for the reply... curious lang po, is there any difference with the denso and zexel noozle tips? for example my original is zexel 121 and i'll change it to denso 121... is it just the same or there is still slight difference even though they have the same number? tnx a lot and God bless.

Of course there is a difference, but the difference my be very slight as both brands manufacture quality parts.

I would however use Zexel for Zexel, and Denso for Denso. If Zexel was the original nozzle, I would use a Zexel, and the same for Denso. And I don't recommend intermixing similar nozzles with different brands on one engine.

I also caution you on fake nozzles as we have seen a lot in the market.

Bye,

Dieseldude

[GundamWing]

sir dieseldude,

Magkano po ba ang isang nozzle para sa isuzu 4ja1 engine ito po ba yung pinapalitan kapag medyo malakas na sa diesel consumption o meron pang ibang pinapalitan aside from the nozzle kapag ganun ang problem. Anong brand nga po pala ng fuel injection system para sa ganitong engine? Zexel or denso po ba?

Thanks,

[Dieseldude]

sir dieseldude,

Magkano po ba ang isang nozzle para sa isuzu 4ja1 engine ito po ba yung pinapalitan kapag medyo malakas na sa diesel consumption o meron pang ibang pinapalitan aside from the nozzle kapag ganun ang problem. Anong brand nga po pala ng fuel injection system para sa ganitong engine? Zexel or denso po ba?

Thanks,

Bukas ko pwede icheck sa office kung ano at magkano ang nozzle ng 4JA1.

Madalas barado lang ang air cleaner mo kapag malakas sa diesel.
Palitan mo nang original Isuzu air filter.

Zexel ang nozzles ng 4JA1.

Bye,

Dieseldude

[GundamWing]

sir dieseldude,

thanks for the reply sir, antay ko na lang price ng nozzle para may idea po ako. nakapag palit na din po kasi ako ng filter.

Thanks!

[sag0]

good day! napansin ko lang po nag uusok na naman yung ride ko. a few months ago nag uusok sya and i had the valves (or injectors... ewan ko ba) adjusted sa casa. i think its the clearance or whatever. but nawala yung smoke. now i want to have it adjusted ulit but not in the casa anymore para cheaper. sa casa mga 1k eh. do you guys happen to know how much magpa adjust nun sa labas? good day! oh by the way, my ride is an isuzu hi-lander xtrm 2000.

thanks!!!

[promdiboy]

sir diesel dude, I had my local pajero with 4m40 engine calibrated at your shop, inabot din ng almost 20k lahat, Everything is ok, and emissions improved alot, from 1.0 to just .28. just want to ask, if lahat ba ng parts exactly the same as my mitsubishi oem? I'm not so sure pero parang iba itsura nung tubes papaunta ng injector, not sure or mali lang tingin ko. would appreciate it kahit konting explanation kung ano ang scope ng calibration, daming parts na pinalitan and test na ginawa but di ko maiintidihan. just want to learn more about my engine, thanks sir, and vey good job on my ride.

[Dieseldude]

sir diesel dude, I had my local pajero with 4m40 engine calibrated at your shop, inabot din ng almost 20k lahat, Everything is ok, and emissions improved alot, from 1.0 to just .28. just want to ask, if lahat ba ng parts exactly the same as my mitsubishi oem? I'm not so sure pero parang iba itsura nung tubes papaunta ng injector, not sure or mali lang tingin ko. would appreciate it kahit konting explanation kung ano ang scope ng calibration, daming parts na pinalitan and test na ginawa but di ko maiintidihan. just want to learn more about my engine, thanks sir, and vey good job on my ride.

I'm glad that you're happy with our service. I reply to your questions: yes, we only use original parts. The high pressure pipes from the injection pump to the injectors would be your original pipes as these don't normally fail.

Though I am not aware of your specific repair order, I have an idea of the calibration work done on your system.

Pump work would cover disassembly of injection pump, parts inspection to determine reusability of parts, replacement of worn out parts and reassembly of injection pump with a new gasket and seal kit, then calibration of injection pump. Calibration is the procedure of adjusting the injection pump to conform to original Zexel test data, specific to your pump, using factory-approved test equipment. This means that the pump will be adjusted to the original factory specifications. We have the factory specifications as Central Diesel is an authorized Bosch/Zexel service station. These specifications are issued only to authorized workshops.

Injector work scope would be similar to pump work, but with fewer parts to replace. Most common injector wear part is the nozzle tip. These are replaced when found to be faulty (fuel drip & poor automization), then adjusted to pop off at the factory recommended opening pressure. Injectors with new nozzles and correct pressure adjustment will ensure proper fuel automization, good fuel burn, and optimum performance.

Thank you for asking these question as it is my hope this reply will benefit others as well.

Bye,

Dieseldude

[Dieseldude]

good day! napansin ko lang po nag uusok na naman yung ride ko. a few months ago nag uusok sya and i had the valves (or injectors... ewan ko ba) adjusted sa casa. i think its the clearance or whatever. but nawala yung smoke. now i want to have it adjusted ulit but not in the casa anymore para cheaper. sa casa mga 1k eh. do you guys happen to know how much magpa adjust nun sa labas? good day! oh by the way, my ride is an isuzu hi-lander xtrm 2000.

thanks!!!

Engine valve clearances don't change that much is just a few months. Therefore, I don't think that valve readjustment will cure your smoke problem.

1K seems to be a fair price for the casa to perform a this service.

Like I've often said, air cleaner replacement may correct your problem.

By the way, is it white or black smoke?

Bye,

Dieseldude

[sag0]

hi! it's gray smoke. and its not really the inky-black smoke on certain trucks and buses. air cleaner? like the air filter? the mechanic said its still okay and he just cleaned it with compressed air. do i have to buy a new one? how about the fuel filter? do i have to change that too? thanks for your reply kind sir!!!

[Dieseldude]

hi! it's gray smoke. and its not really the inky-black smoke on certain trucks and buses. air cleaner? like the air filter? the mechanic said its still okay and he just cleaned it with compressed air. do i have to buy a new one? how about the fuel filter? do i have to change that too? thanks for your reply kind sir!!!

Gray smoke is not a true gauge of emission levels. We can do a smoke test on your Highlander free of charge.

Air filters become restricted after extended use, and will cause black smoke. Blowing compressed air cannot remove all the caked-in fine dust particles. You can try removing the air filter just to check if smoke levels improve.

Fuel filter replacement will not improve emissions. A blocked fuel filter will result in fuel starvation, less smoke, and less power.

Bye,

Dieseldude

[cocoy]

sir how much would it cost to have my injectors checked out at your shop? i just want the proper opening pressure back to original specs.. and by the way how much would it also cost to replace the springs inside the injector assembly.. thank sir..

[GundamWing]

nakakapag cause din ba ng white smoke not the normal gray kapag wala sa proper setting ang fuel injection system yung parang hilaw yung burn? pansin ko kasi din sa ride ko kapag medyo cold pa yung engine tapos medyo hirit ng konti sa accelerator lumalabas sya pero nawawala din kapag medyo matagal na sya nagamit, madalas din sinasabi ng mga isuzu 4ja1 owners na normal yung white kapag cold pa engine but mine is thicker white smoke. I checked my oil everyday morning kung nagsusunog na sya ng oil pero consistent naman yung level ng oil nya nasa max level. Im also thinking that it might be my valve seals pero im not sure or yung mga naliligaw na nahihigop na oil from the air breather galing sa valve cover direting to the air intake. Kakapaadjust ko lang din ng valve clearance ko last two weeks pino naman yung andar. medyo mahina din hatak and 8km/L consumption ko pero tyaga lang muna ako kasi wala pa budget kung magpapa calibrate ako, sana meron ng christmas bonus hehehe

[the_possessed]

Doc Diesel,

I have poor engine performance specially on hills.. I went to Speedy Fix since i was suspecting that it could be my clutch.. but the chief mechanic said that my clutch is ok.. However, He said "sakal" daw ung hatak ng Engine ko.. This happend after my diesel calibration almost 2 years ago.. He said, a calibration shop should be able to do minor adjustment to release it..

Do you think this is the case?

Thanks!

[monmendoza]

Hello DieselDude,

I was in Central Diesel Clinic this afternoon but you were not around because it was lunchtime. I was palnning to wait for you but one of your staff seeing me waiting volunteered to see my LJ 71 even if it meant that he has to interrupt his lunch. He ask me to open the hood and start the engine and ask me what is the problem. I told him that it gives black smoke when I am overtaking and the rpm is high, so he ask me to show it to him. Then he told me to first clean my exhaust system because the engine sounds fine. He told me to go back, if flushing my exhaust with water will not remove the black smoke. He said personally the sound of the engine indicates its still in tip top condition. Very impressive.

I am very impressed. They are customer oriented and they are not greedy and eager to make a fast buck at the expense of the customer. Some unscrupulous mechanic might imeediately recommend an overhaul. If the problem will not be solve, or when new problems crop up I will definitely bring it to your place.

[promdiboy]

thanks sir diesel dude,

[Dieseldude]

Hello DieselDude,

I was in Central Diesel Clinic this afternoon but you were not around because it was lunchtime. I was palnning to wait for you but one of your staff seeing me waiting volunteered to see my LJ 71 even if it meant that he has to interrupt his lunch. He ask me to open the hood and start the engine and ask me what is the problem. I told him that it gives black smoke when I am overtaking and the rpm is high, so he ask me to show it to him. Then he told me to first clean my exhaust system because the engine sounds fine. He told me to go back, if flushing my exhaust with water will not remove the black smoke. He said personally the sound of the engine indicates its still in tip top condition. Very impressive.

I am very impressed. They are customer oriented and they are not greedy and eager to make a fast buck at the expense of the customer. Some unscrupulous mechanic might imeediately recommend an overhaul. If the problem will not be solve, or when new problems crop up I will definitely bring it to your place.

Hi Mon,

I'm glad to hear this from you.

Some city driven diesels do accumulate soot on the exhaust pipes if they are not driven hard from time to time.

Bye,

Dieseldude

[Dieseldude]

thanks sir diesel dude,

You are welcome.

Bye,

Dieseldude

[Dieseldude]

Doc Diesel,

I have poor engine performance specially on hills.. I went to Speedy Fix since i was suspecting that it could be my clutch.. but the chief mechanic said that my clutch is ok.. However, He said "sakal" daw ung hatak ng Engine ko.. This happend after my diesel calibration almost 2 years ago.. He said, a calibration shop should be able to do minor adjustment to release it..

Do you think this is the case?

Thanks!

Speedy Fix mechanic is probably correct about the "sakal". But "sakal" could be due to a blocked fuel filter, improperly adjusted accelerator cables/linkages, or faulty injection pump adjustments. I would first check on the fuel filter, then the linkages. You could probably ask the previous shop who worked on your pump to do the necessary correction. Tell them that you were never happy with the engine's performance since they worked on your pump. I am sure they will help you on this.

Bye,

Dieseldude

[Dieseldude]

nakakapag cause din ba ng white smoke not the normal gray kapag wala sa proper setting ang fuel injection system yung parang hilaw yung burn? White smoke is not a good sign as this could be an engine problem. But before working on the engine, I would first check injection pump to engine timing, valve clearances, and injector condition.

pansin ko kasi din sa ride ko kapag medyo cold pa yung engine tapos medyo hirit ng konti sa accelerator lumalabas sya pero nawawala din kapag medyo matagal na sya nagamit, madalas din sinasabi ng mga isuzu 4ja1 owners na normal yung white kapag cold pa engine but mine is thicker white smoke. White smoke when cold, which then normalizes as engine temp increases could be a sign of poor engine compression. Cold engines have larger clearances, therefore lower compression pressures. As engine temperature increases, the pistons thermally expand, and lube oil wets the piston rings and improve their sealing function, which have an effect of improving compression. This is the reason why you have less white smoke pag matagal mo na nagamit ang sasakyan.

I checked my oil everyday morning kung nagsusunog na sya ng oil pero consistent naman yung level ng oil nya nasa max level. Im also thinking that it might be my valve seals pero im not sure or yung mga naliligaw na nahihigop na oil from the air breather galing sa valve cover direting to the air intake.
Excessive oil gas discharge from the valve cover is a definite indication of compression loss through the piston rings. Compression gasses pass through the piston/piston ring/and cylinder walls; fill up the engine block, and these gasses escape through the valve cover breather. You may need to check your engine's compression pressure.

Kakapaadjust ko lang din ng valve clearance ko last two weeks pino naman yung andar. medyo mahina din hatak and 8km/L consumption ko pero tyaga lang muna ako kasi wala pa budget kung magpapa calibrate ako, sana meron ng christmas bonus hehehe

Your problem is probably not caused by the fuel injection system.

Did you experience previous engine overheat situation/s?

Bye,

Dieseldude