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Engine Specific Info and Questions => IDI Engine => Topic started by: matrick on January 21, 2020, 01:29:29 am
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I have an AAZ that's always been a little sluggish. I'd been driving it with the cold start lever constantly pulled out because it would stall otherwise. This lead me to believe the timing was too retarded. When I checked it, it was at 0.73mm, which is within the "check range" but I decided to set it to 0.80mm anyway. Well, it still stalls without the cs lever pulled. After reading some forum posts, I found that a lot of people were setting theirs to 1.00 or even 1.05. It doesn't seem normal to me that the car would be stalling (even when fully warmed up) when pushing the cs lever in and letting it use the static timing of 0.80, considering that's the factory timing spec. Will setting mine to 1.00 fix my issue or is there another underlying cause?
If it makes a difference, my downpipe is also completely split in half at the flex connection so I have almost no exhaust. (already have the new one ready to install, just need time...and warmer weather!)
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The AAZ injection pump cold start lever setup both increases the timing at idle AND it raises the idle RPM. Your stalling issue might not be timing related and might just be that your idle speed is set too low.
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I don't think that's the case because at idle with CS lever out I sit around 1100, with it in I'm right around 900 where (I believe) it should be. (correct me if I'm wrong)
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The car doesn't quite stall immediately when CS lever is pushed in. It just has almost no power. Just barely enough power to get into first gear.
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With 'poor power' as the symptom, there are a slew of other potential causes aside from injection pump timing. Give more details... like, how long have you had the car? Is this a new issue? What have you checked so far? What maintenance have you performed, e.g. fuel filter, air filter? Any air in the fuel line to the injection pump? Any fuel leaks? Etc... Etc... Etc...
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I should also reword my initial post... The fact that pulling the cold start helps prevent stalling is most likely due to raising the rpms and has nothing at all to do with advancing the timing.
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Even though .80 might still be a little low.
White smoke out the exhaust?
Clear fuel lines?
Edit: since it is an AAZ,...
crank pully on solid?
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Sorry for the late reply, guys. I've had the car for just about a year now and it's been like this since I got it. So far the only engine work I've done to it is an oil change and glow plugs. No fuel leaks, and I don't have a clear fuel line so I can't check for bubbles. Should I put a clear hose in asap?
Before changing the timing from .73 to .80, the car would stall after running rough for a few seconds with CS in. Now I can actually drive the car to a certain degree with CS in, but getting into 1st is a struggle and I don't think it would be able to get into 1st on an incline. That leads me to believe it's more so the advance than the idle increase, because I could just hold the RPM higher while trying to get into first, but it doesn't feel the way it does when CS is out.
Crank pulley is good and it has the 12 point bolt so it should stay good, right? No noticeable white smoke from exhaust, although the fact that the exhaust just dumps into the engine bay may be preventing me from seeing it. I've had the hood open while it was running though and didn't notice any white smoke (aside from right after startup).
Also a question about the crank pulley: if it was loose I'd be able to just wiggle it and feel that, right?
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Yeah, get clear fuel lines right away.
From the filter to the pump
and from the pump back to the tank.
You should also have clear line between injectors
but if they are pumping air into the return line you'll see it
with the clear line going back to the tank.
So at .73 you could notice a difference when you pulled the cold start?
Pulled the cold start and it ran better?
You know the cold start advances timing right?
The cold start lever is a pretty handy tool for setting the timing.
How the car runs with it and cold says alot.
I don't understand why you are having a problem getting into 1st.
I could grab the crank pully and wiggle it on the 1.6 that went.
But it was after it went
Someone else might have more experience with this.
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Getting the car into 1st is an adjustment you make on the rod that comes under the car from the shifter. There is a proper amount of forward and back play in that rod that makes it possible to get into the 1st and 3rd gear. There is also an amount of side to side play that is required to be able to get into 3rd and reverse.
Adjustment procedure is in the Bentley. All it takes is a 13 mm socket to loosen the bolt that holds the rod in place just behind the transmission support bracket in the rear.
I may have to fiddle with the Caddy when the rain lets up, if it does, as I was experiencing a difficult time locating 1st on the way home tonight.
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By "getting into 1st," I just meant having the car actually start moving in 1st without stalling.
What I really want to know is this: Is it normal for my car to be under powered with the injection timing set to .80? The reason I question this is because I know a lot of people set theirs to 1.00 and they say that the cars come much too retarded from the factory.
And I mean under powered to the point where I'm pretty sure the car would stall when trying to get going from a stop on a fairly moderate incline.
As far as the clear lines go, is there someone that makes clear lines that just fit right up or do I just have to find clear tubing that is the correct diameter and cut it to length? If I have to find my own, are there any things I should take into consideration when selecting the tubing as far as material or temperature specifications or anything or will any clear rubber line work?
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Are you pressing the accelerator while releasing the clutch?
If so, then I'm going to say that assuming you are measuring the timing properly, then no, your timing setting is not causing the low power issue. You might gain a small amount of power by adjusting the timing, but not enough to make the difference between stalling or not.
When was the timing last done? Compression check? Fuel filter? Air filter? Leaks at intake or exhaust manifolds? Air in fuel? Etc, etc, etc...
My recommendation is to stop fixating on the fine timing and start diagnosing with a systematic approach to any checks/maintenance that you do not know to have been performed recently.
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That's what I was thinking. Alright, so I'll start basic low power diagnosis then. Thanks!
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OK I understand it this way. You are in 1st and you want to go forward. Level ground it doesn't want to "rev up" so you can play the clutch and peel out like, well a Rabbit.
Some of the issues have been noted previously. Timing- couldn't hurt to bump that to 1.0 for good measure. Idle- 800 RPM could adjust the CS pull out to be at 1200 and see if that improves things. Screwing in the fuel screw in might do a two for one fix. Give you more fuel earlier and increase the idle.
That is where I would be spending my time. See if I could get better results off clutch with a higher idle and more fuel. If that really doesn't make a difference then advance the pump some. They are retarded to meet NOX requirements. Nothing can be gained leaving it there if you want some power.
Have you checked for dragging brakes, sticking ebrake cables, Jack it up and see if they all spin freely with all the releases let go.
Other than these items follow the other suggested items and report back.
Here is to hoping you find the problem
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I don't use a dial gauge when setting timing.
But looking it up in the Bently shows .83 to .93 is the standard range.
.80 is below even the lowest suggested setting
Performance is .93 to about 1.
It could also be the max fuel screw is out too far.
Clear fuel line can be found at your local hardware store.
That's still where I'd start.
Kinda sounds like fuel starvation.
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I've probably read this reply a dozen times and just processed that you do it without using a dial gauge. How exactly do you do it then?
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I time it by ear.
On the edge of clackity.
Make a mark.
Move it and see.
Then move it again.
It couldn't hurt for you to advance it.
If you don't like it move it back.
I also have a pulse detector,.. so I can use a timing light and set it to 12 BTDC.
According to Andrew your pump has the RPM advance too.
So pulling it all the way doesn't just indicate sounds changes during timing advance.
He's more familiar with the 1.9 stuff.
Get clear fuel lines first.
To and from the pump.
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Try adjusting the fuel mixture too, 12 mm wrench and long screw driver flat. That seems to smooth it out sometimes and raise or lower rpms a bit.
Once warmed up, it should idle and run with cold start pushed in set at .82 mm.
Mine did.
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There is no 'mixture' adjustment on a diesel. That is gasser thinking and does not apply to unthrottled diesels. They always ingest as much air as they can. Increasing the fuel will raise the rpms.
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Thats what I meant, the screw that feeds more fuel. of course not air... I know its wide open on a diesel, So fuel mixture is maybe wrong term but you get the idea.
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I assume you are talking about the max fuel screw. That screw changes the scale of the entire fuel map and so affects both idle and the top of the pedal. If the goal is to change the idle speed, then that is the wrong screw to use. If the goal is to change the amount of fuel at a fully floored pedal then it is the correct screw to adjust and then idle needs to be adjusted afterward using the idle screw.