Low idle at start, rises when warmed up :HDJ81 (1 Viewer)

[Jroc561]

On colder mornings(for here) so 30 degrees or so, the car has a rough idle for the first minute which seems to stem from a low idle. But after awhile it creeps up to 800 and it sounds and acts normal.

I’m used to most cars doing the opposite, high idle then once warmed up it lowers.

Auto 1HDT
ACSD deleted

Again only happens on cold starts, or atleast only noticeable

 

[SHREDwagon]

Pump timing should be advanced to the upper end of the spec with the ACSD removed. You can use the hand throttle until then.

 

[AussieHJCruza]

Seems to be typical with acsd deleted, as @SHREDwagon said, advance timing to top end of spec and give her a bit of throttle when she's cold

 

[Nz Nath]

High idle when cold would have to be due to electronic idle up? Both petrol and diesel engines without such electronic witchcraft always idle slow or not at all when cold?

 

[Jroc561]

Thank fellas, thats the information I needed. I know the idle screw wouldnt do anything for this circumstance, pretty positive this thing didnt have an IAC like the petrol version.

Now I know what needs to be done.

 

[Jonchez]

@Jroc561 what did you end up doing about your idle issues?

 

[Jroc561]

While my rig isnt 100% straighten out yet, what solved most of the hard start issue was replacing the pump primer. One day I went to test if priming the pump with a few pumps would make for a smoother start and I noticed some diesel leaking out from the actual hand pump area.

I also loosen one of the injectors joints to see if I could get any air out. I would still like to eventually put a clear tube in there to see if I still have air in the system and it also needs to be truly re-timed since I removed the ACSD but it starts alot better/smooter from when I started this thread by getting some air out of its system.

Hope that helps

 

[Squash]

No need to screw with the timing. Your deleted Acsd was only active till the engine warmed up, and then it went to sleep. Your engine spends most of it's time driving at operating temps and that's where you want the timing.
Use your hand throttle until she's warm and don't forget to help the system by using the fuel pedal to find the sweet spot before you lock in the hand throttle.

 

[Jonchez]

While my rig isnt 100% straighten out yet, what solved most of the hard start issue was replacing the pump primer. One day I went to test if priming the pump with a few pumps would make for a smoother start and I noticed some diesel leaking out from the actual hand pump area.

I also loosen one of the injectors joints to see if I could get any air out. I would still like to eventually put a clear tube in there to see if I still have air in the system and it also needs to be truly re-timed since I removed the ACSD but it starts alot better/smooter from when I started this thread by getting some air out of its system.

Hope that helps

Thank you for the reply. I talked to some people from Australia and they say it is the damper spring that senses a load. The spring weakens over time and is not a part they would change if you had your pump serviced.
I am not keen on taking the pump apart but hour it helps you narrow down your issue.

 

[roscoFJ73]

But after awhile it creeps up to 800 and it sounds and acts normal.

Do you have a hand throttle on the dash? Try turning it up to 1000rpm on a cold start. Thats what its for.

 

[AussieHJCruza]

Perfectly normal for a 1HDT with an ACSD delete, mine did the same when I deleted ACSD. Try an early 2H without superglow - mine wants to idle at about 500 rpm when it's cold and rattles your teeth out

 

[chapel gate]

I'm one of the few people in the world that doesn't hate the ACSD.
I like the "choke" effect it gives.
When mine started leaking I replaced it with a new one.

I'm aware of issues some have had.

 

[crave reFleXion]

Agree with all above. I've got a 14BT which I did an ACSD delete last year. Currently, as we're coming into Winter (if you can call it that in North Queensland), I've noticed a change in starts with it wanting to idle at 600rpm at first. I simply use the hand throttle for the first 1-2 minutes and then it's fine.

 

[crave reFleXion]

I'm one of the few people in the world that doesn't hate the ACSD.
I like the "choke" effect it gives.
When mine started leaking I replaced it with a new one.

I'm aware of issues some have had.

Personally, I think it really depends on the climate you live in. Anywhere 'tropical', I think it's completely unnecessary and the potential harm caused when they break to the pump is a risk I would'nt want to take. I saw a pump that had an ACSD failure and it's pretty shocking.

 

[Nz Nath]

I disconnected the glow screen on my 13bt, as the relay was playing up. On any cold starts I just give it a bit of right pedal and it fires straight up (haven't seen below 5c). Down to about 10c it wants a high idle for about 10seconds, and 5-10c about 20seconds. I don't have a hand throttle so I just use the accelerator pedal, not a big inconvenience.

With the glow screen working (manual not superglow) it would fire up with no throttle at 0c, and idle a bit lumpy but not bag of spanners lumpy. I guess the after glow that you get with superglow would help there

 

[Jroc561]

This is great info, not ever being around another 1hdt or toyo diesel im not sure what is "normal". Glad to know people find using the hand throttle for cold startups even in warm climates(aus) to smooth out the early lumpiness/low initial rpm is just normal course of business.