Injector Duration - misfire
 

I've had a misfire for quite a while, that I've been living with in my MY00 Turbo. I can be at a constant 1750rpm at 30mph, and the injector duration is around 4.5 odd milliseconds. I notice it then drops to 0.51 ms, or perhaps that's just the lowest reading my data monitor shows, but it obviously is a noticeable difference.

Could it be the 22 year old injectors? Things I have changed, leads, plugs, MAF, fuel filter and fuel pump and sock. I've swapped the coil pack over as I have 3 of them, all of similar age, that didn't make a difference. I will also have access to another 2 sets of injectors, of a similar age too. Should I swap them out, or should I get a set cleaned/flow tested and put them in?

Are you sure its reading the measured pulsewidth and not just showing you the commanded pulsewidth? If its showing the command value then look for reasons why it would suddenly need such a small amount of fuel - maybe tps/map/maf readings are actually to blame.

It's actually a reading form my PSI3 data monitor and I can't find any more details on how its obtained I will have to do some digging. Thanks

The psi3 reading will be what the ecu is requesting the injectors to do not measuring what they are doing.

I had a misfire on a 80k mile blob some years ago, and was assured by 2 "experts" that it was highly unlikely to be injectors, so I replaced just about everything else to no avail. Finally I had the injectors cleaned by Injector Tune in Wiltshire and it was like a new car, gaining considerable power as well.
Injectors are rarely considered for maintenance, but fuel cannot ignite optimally without correct spray patterns

You've mentioned on another thread about your rear reverse lights....the neutral position switch is often first port of call for misfires.

have "solved" many Gen4 JDM Legacy issues over the years by cleaning their injector set-up so it certainly does and can have an impact as above.....

Thanks all.

I will check the neutral position switch too.

With regards to the injectors, should I try something like redex for a bit, or just get the cleaned properly? I rally don't do too many miles either way. So I suspect the redex option could take a while to get through

any of the tank additives whilst being partially successful to some degree can never achieve the results of a proper testing / cleaning regime

it also won't tell you if you have a 'faulty' unit and more importantly that it has been resolved

As Alyn says, no cleaner can compare with ultra sonically cleaned jets, fresh baskets, electrical test and before and after values. But they are a ******* to get to if you're doing it yourself....well it was for me, not called the bracket of death for nothing!

https://www.injectortune.co.uk/index.html
found these guys to be good value, £15 an injector. Just as important a service as your spark plugs!

Thanks for the link. I'll certainly look into using them once I can get them off. I do have access to another 2 sets of injectors, on 2 different engines. So I'll get some practice in removing them.

Im guessing Injector cleaning will become part of the servicing soon, especially on little used cars and the new fuels,
Mine are over 20 years old now, might be worth a clean and flow test.