1HZ not all injectors seem to be working straight away on start-up when cold (1 Viewer)

[sunrk]

Just finished the 80's timing belt, t-stat, water pump, etc. service work.

One thing I noticed after starting the motor is the same problem it's had for some time in that it seems to not run on all the injectors at initial start-up from cold and for a short while it acts like it's stumbling a bit as though it's got a cylinder (or two) down, but after a while it's idling nice at about 750 rpm. Replacing the injectors is another job still on the list just like the valve shims.

I'm betting it's an injector causing this but curious what others think. The other artefect is that when it's idling, you can feel and hear the motor 'burp' randomly but I have never noticed any odd coloured exhaust (like blue indicating burning oil, or white indicating coolant getting into the cylinders).

I do have a full set of new genuine injectors to fit to the motor plus the seats and a new return rail. I might run some diesel injector cleaner with the next fuel fill in the meantime.

Injectors were refurbed ones fitted when injector pump was also replaced by a diesel shop at about 510 k km's about 12 yrs ago. Pump has no leaks btw.

 

[Eurasiaoverland]

Sounds exactly like the glow plugs are not all working. Less likely to be an injector if the problem is only when cold.

The next most likely would be air getting into the system once the engine stands for a while. The odd hiccup when running is likely to be air.

 

[mudgudgeon]

100% agree with above.
Test or replace glow plugs first IMO