Hard cold start

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VWinVT
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Hard cold start

Post by VWinVT » Mon Oct 12, 2015 2:13 pm

I am struggling with getting this issue sorted out. I have a 81 (California) Westy. For about 2 months now, it has started hard when cold. If I don't give it some gas pedal it will not start. If I don't 'catch' it on the first attempt to start; I will then need to put the pedal to the floor to get it to start.
I just finished going through the cold start, ThermoTime, and AAR checks and it all works properly.
I have followed the procedure to adjust the AFM and when it is running, I have great power and nice cool head temps. Today driving home was cruising 55 at 360* (DD gauge).
Timing is set properly.
My gas mileage is only 15mpg.
Thinking that I may have it too rich, I went to,lean it out when I got home from work. I leaned out idle but the RPM mixture was too lean. I then adjusted the black cog and the wiper arm moved with the cog....I flooded motor and would not start again.
I walked away......
Is the wiper arm supposed to moved when the black cog is moved? I don't seem to remember this happening before. Unfortunately I started the AFM adjustments before I tracked all the vacuum leaks down ( I though I did but they kept popping up). I just recently blocked off the EGR ports.
I LOVE my van, but this motor is driving me crazy!! :bounce:
I need some help!

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Amskeptic
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Re: Hard cold start

Post by Amskeptic » Mon Oct 12, 2015 6:04 pm

VWinVT wrote: I leaned out idle but the RPM mixture was too lean.
I then adjusted the black cog and the wiper arm moved with the cog....

Is the wiper arm supposed to moved when the black cog is moved?
I need some help!
What do you mean, the wiper arm moved when the cog was adjusted?
You need to be specific with details like, which way did you move cog? How many teeth?
Did the wiper move as a result of the vane having less resistance with a weaker spring, or did it move because it was not securely clamped?

Is there any reason you cannot merely bring your adjustments back to their initial settings, then readjust?
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

VWinVT
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Location: Northeast Kingdom Vermont
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Re: Hard cold start

Post by VWinVT » Mon Oct 12, 2015 11:32 pm

Amskeptic wrote:
VWinVT wrote: I leaned out idle but the RPM mixture was too lean.
I then adjusted the black cog and the wiper arm moved with the cog....

Is the wiper arm supposed to moved when the black cog is moved?
I need some help!
What do you mean, the wiper arm moved when the cog was adjusted?
You need to be specific with details like, which way did you move cog? How many teeth?
Did the wiper move as a result of the vane having less resistance with a weaker spring, or did it move because it was not securely clamped?

Is there any reason you cannot merely bring your adjustments back to their initial settings, then readjust?
Colin

The van was running at idle. I loosened the screw at the base of the wiper arm and adjusted the wiper arm clockwise to make the mixture a bit more lean.

I then checked the higher rpm mixture and it was too lean. I let the motor go back to idle and then moved the black cog counterclockwise. It was a bit hard to turn. It turned 5 or 6 teeth (it turned faster than I expected once it moved). The wiper moved counterclockwise with the cog...flooding the motor and it stalled.
With the the motor off I checked this out and any more then 4 or 5 teeth on the black cog and the wiper arm will move with it...limiting the adjustment. The screw at base of wiper arm is loosened during this.

When I first adjusted the AFM awhile back, I recall the big black cog and the wiper arm moving/adjusting independent of each other.

I have put the wiper arm back to where I started, but the cog won't let me go back to its starting point...it moves the wiper also. My mixture was terribly lean when I started. As I tracked down countless vacuum leaks, timing issues, distributor issues, blocked of AAR hoses (bolt), dodgy wiring...u get the idea...I would adjust the AFM accordingly. I am thinking I messed up the mechanicals of the AFM......

Now all those issues are sorted and when running, the motor runs really strong and cool. But cold starts are a struggle. Hot starts are a breeze.

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Amskeptic
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Re: Hard cold start

Post by Amskeptic » Tue Oct 13, 2015 7:49 am

VWinVT wrote:the cog won't let me go back to its starting point...it moves the wiper also.

Now all those issues are sorted and when running, the motor runs really strong and cool. But cold starts are a struggle. Hot starts are a breeze.
There is no physical connection between the two.
You can adjust the cog with the engine off and the wiper in its parked position.

Therefore, I am attempting to comprehend what you are saying. If you get a dynamic (air flow/spring tension) CHANGE in wiper position when you adjust the cog, that is not a "won't let me" moment, it is merely a known effect that we have to compensate for.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

VWinVT
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Location: Northeast Kingdom Vermont
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Re: Hard cold start

Post by VWinVT » Tue Oct 13, 2015 9:51 am

Amskeptic wrote:
VWinVT wrote:the cog won't let me go back to its starting point...it moves the wiper also.

Now all those issues are sorted and when running, the motor runs really strong and cool. But cold starts are a struggle. Hot starts are a breeze.
There is no physical connection between the two.
You can adjust the cog with the engine off and the wiper in its parked position.

Therefore, I am attempting to comprehend what you are saying. If you get a dynamic (air flow/spring tension) CHANGE in wiper position when you adjust the cog, that is not a "won't let me" moment, it is merely a known effect that we have to compensate for.
Colin
Ok, since it seems my AFM is not functioning as it should, because the cog moves the wiper, what do I need to do to compensate/correct this issue?

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Amskeptic
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Re: Hard cold start

Post by Amskeptic » Tue Oct 13, 2015 2:29 pm

VWinVT wrote:
Amskeptic wrote:
VWinVT wrote:the cog won't let me go back to its starting point...it moves the wiper also.

Now all those issues are sorted and when running, the motor runs really strong and cool. But cold starts are a struggle. Hot starts are a breeze.
There is no physical connection between the two.
You can adjust the cog with the engine off and the wiper in its parked position.

Therefore, I am attempting to comprehend what you are saying. If you get a dynamic (air flow/spring tension) CHANGE in wiper position when you adjust the cog, that is not a "won't let me" moment, it is merely a known effect that we have to compensate for.
Colin
Ok, since it seems my AFM is not functioning as it should, because the cog moves the wiper, what do I need to do to compensate/correct this issue?
I seriously need a tight descriptive explanation as to how the cog is moving the wiper. I STILL don't know if you are describing a physical interference vs a dynamic change in fuel mixture. Really. I don't yet know.
Colin :scratch:
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

VWinVT
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Location: Northeast Kingdom Vermont
Status: Offline

Re: Hard cold start

Post by VWinVT » Tue Oct 13, 2015 3:52 pm

Amskeptic wrote:
VWinVT wrote:
Amskeptic wrote:
VWinVT wrote:the cog won't let me go back to its starting point...it moves the wiper also.

Now all those issues are sorted and when running, the motor runs really strong and cool. But cold starts are a struggle. Hot starts are a breeze.
There is no physical connection between the two.
You can adjust the cog with the engine off and the wiper in its parked position.

Therefore, I am attempting to comprehend what you are saying. If you get a dynamic (air flow/spring tension) CHANGE in wiper position when you adjust the cog, that is not a "won't let me" moment, it is merely a known effect that we have to compensate for.
Colin
Ok, since it seems my AFM is not functioning as it should, because the cog moves the wiper, what do I need to do to compensate/correct this issue?
I seriously need a tight descriptive explanation as to how the cog is moving the wiper. I STILL don't know if you are describing a physical interference vs a dynamic change in fuel mixture. Really. I don't yet know.
Colin :scratch:
It is a physical interference resulting in a dynamic change in fuel mixture...when I move the black cog more than 5or 6 cogs...the wiper arm physically moves in the same direction that I am turning the cog. Is there a way to repair my broken AFM, or do I need to buy a new one?

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Amskeptic
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Re: Hard cold start

Post by Amskeptic » Tue Oct 13, 2015 5:27 pm

VWinVT wrote:
Amskeptic wrote:
VWinVT wrote:
Amskeptic wrote:
VWinVT wrote:the cog won't let me go back to its starting point...it moves the wiper also.

Now all those issues are sorted and when running, the motor runs really strong and cool. But cold starts are a struggle. Hot starts are a breeze.
There is no physical connection between the two.
You can adjust the cog with the engine off and the wiper in its parked position.

Therefore, I am attempting to comprehend what you are saying. If you get a dynamic (air flow/spring tension) CHANGE in wiper position when you adjust the cog, that is not a "won't let me" moment, it is merely a known effect that we have to compensate for.
Colin
Ok, since it seems my AFM is not functioning as it should, because the cog moves the wiper, what do I need to do to compensate/correct this issue?
I seriously need a tight descriptive explanation as to how the cog is moving the wiper. I STILL don't know if you are describing a physical interference vs a dynamic change in fuel mixture. Really. I don't yet know.
Colin :scratch:
It is a physical interference resulting in a dynamic change in fuel mixture...when I move the black cog more than 5or 6 cogs...the wiper arm physically moves in the same direction that I am turning the cog. Is there a way to repair my broken AFM, or do I need to buy a new one?
"when I move the black cog more than 5or 6 cogs...the wiper arm physically moves in the same direction that I am turning the cog" With the engine off? If it is idling, that is normal and expected. That is why we adjust the cog/wiper.

Let's exaggerate for effect. If you move the cog 124 teeth counter-clockwise on an idling engine, there is very little spring tension left. Then your idle air flow would swing that vane (and therefore the wiper) waaay rich. That is the intended effect of this adjustment.

Correspondingly, let's say you move the cog 124 teeth clockwise. That makes the spring stronger. Therefore, whatever air flow is entering the engine does not move the wiper as much as it would with a weaker spring. This leans the mixture. That is the intended effect of this adjustment.

I do not understand this physical interference you speak of, as though the cog were jamming against the wiper.

When we adjust the cog, the mixture changes. That is why we adjust the cog. Let's say you adjusted the wiper richer for an exact 10.9 a/f ratio at 55 mph under full throttle. Let's say that the unknown effect is that you also caused a too rich idle now. But that 10.9 @55 sure is wonderful. Sorry! You have to tighten the cog to lean out the idle mixture THEN go back and check the full throttle mixture at 55 mph. Perhaps it is now 12.1. Well, trim the wiper adjustment richer a tad back to 10.9 at this new cog setting. Now you have to go back and see if the idle went richer as a result of the wiper trim adjustment. This time, you can hit the mixture screw ccw to see if that will take care of the idle a/f ratio satisfactorily.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

VWinVT
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Location: Northeast Kingdom Vermont
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Re: Hard cold start

Post by VWinVT » Tue Oct 13, 2015 6:28 pm

Yes, the wiper arm moves when I move the cog when the engine is NOT running. Is this expected?

I do understand the concept of the of the AFM adjustment and have spent hours trying to fine tune my mixture based on your write up. Unfortunately, my motor had several hidden issues that my otherwise novice mechanic abilities did not see. So, I continued to adjust and readjust the AFM in response to the corrections I made (timing wrong, vacuum can broken, wrong distributor, leaking injector seals, PS intake air leak due to tin under intake, frayed wiring, cracked vacuum hoses, leaking EGR, exhaust leaks, etc.

When I began adjusting the AFM, the cog DID move completed independently from the wiper arm when the motor was off. During an adjustment a few months ago, the cog started to cause the wiper arm to physically move when it is adjusted.

Do you know if the AFM can be repaired so that the cog and the wiper arm can once again be adjusted without causing physical interference upon each other?

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Amskeptic
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Re: Hard cold start

Post by Amskeptic » Wed Oct 14, 2015 6:22 pm

VWinVT wrote:Yes, the wiper arm moves when I move the cog when the engine is NOT running. Is this expected?
No. This is an amazing thing. The wiper is supposed to park with the engine off. It is supposed to be only attached to the vane shaft. L :cyclopsani: :cyclopsani: K for a cause of physical interference. Can you still move the wiper freely regardless of the cog's effect?

Would you like to procure a fresh AFM?
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

VWinVT
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Location: Northeast Kingdom Vermont
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Re: Hard cold start

Post by VWinVT » Thu Oct 15, 2015 3:31 pm

I would rather repair the one I have, than purchase a new one. Perhaps some time on the bench, under the lights will yield a solution.

VWinVT
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Re: Hard cold start

Post by VWinVT » Thu Oct 15, 2015 6:15 pm

I can't see anything wrong...the cog spring seats in a notch (black plastic) below the wiper assembly. It looks like it suposed to b that way. Perhaps it was 'broken' when I recieved the van. IDK. My cold start issues remain with a lean mixture or a rich mixture. So, I have repositioned the AFM to where I had it and ran 16 mpg with good power and 360-370CHT.
I did just replace the fuel filter and my butt dyno noticed a nice boost in power. Still hard cold starts. Perhaps fuel pressure regulator or weak fuel pump? Time to test fuel pressure?
Am I expecting too much from the FI system? Should I be able to simply turn the key, no gas pedal action, and the van just starts and idles smoothly on its own? It never has, unless it is already warmed up.

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Amskeptic
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Re: Hard cold start

Post by Amskeptic » Thu Oct 15, 2015 7:50 pm

VWinVT wrote:I can't see anything wrong...the cog spring seats in a notch (black plastic) below the wiper assembly. It looks like it suposed to b that way.
Can you still move the wiper freely regardless of the cog's effect?
VWinVT wrote: I did just replace the fuel filter and my butt dyno noticed a nice boost in power.
Seriously? Did you check the old filter for crud / obstruction? Did you your fuel pump "sing" before the filter replacement? Most fuel obstruction symptoms are far more dramatic than "loss of power" that is neatly restored with a new filter.
VWinVT wrote: Still hard cold starts. Perhaps fuel pressure regulator or weak fuel pump? Time to test fuel pressure?
Well, if your fuel filter restored your power, why would you then blame the fuel pump that delivered that "nice boost in power" on a difficult cold start? We do not throw parts at the wall and see what accidentally fixes the car, here.

Cold start valve gets the engine running off the starter. When you let go of the key, it is out of the picture.
AAR keeps the engine running through heavy cold oil by adding more air flow around the throttle plate After five minutes, it is out of the picture.
TS I and II continually adjust the injection pulse width to compensate for variable engine and air temperature.
VWinVT wrote: Should I be able to simply turn the key, no gas pedal action, and the van just starts and idles smoothly on its own? It never has, unless it is already warmed up.
Yes when new.
Older engines with carbon in the intake tracts and crusted on the intake valves, with worn guides, reduced compression, etc, can often take a little longer to get lit. The BobD, my '78 at 110,100 miles, takes five or six compression strokes to get going, idles at 1,200 rpm for one minute, drops to 1,100 rpm, and is at warm idle of 1,000 rpm after about three minutes.

If not catching quickly enough:
Reset plug gaps to .024"
When you crank your engine first thing in the morning, try depressing the accelerator once only after starter is cranking.

If not idling fast enough when cold:
Reset AAR to open more.
Check idle speed when warm, set to 1,000-1,050 rpm.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

VWinVT
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Location: Northeast Kingdom Vermont
Status: Offline

Re: Hard cold start

Post by VWinVT » Fri Oct 16, 2015 7:59 am

EFM-If the screw is loose for the wiper, then yes, I can move it freely and independently of the cog's input. Once the screw is seated, when I move the wiper, the cog spring responds accordingly.

Fuel filter-I have not cut old filter open yet. After reading your response, I guess it is silly to look to the pump et. al. since it seems to give good power when warm, driving.

Cold Start-Perhaps I am being too picky? When I turn the key, the motor 'catches' instantly. If I do not give it one quick shot of gas pedal, it will die. After the quick shot of gas pedal, it will idle on its own...albeit a bit lumpy and chuggy. After 4-5 minutes, she purrs like a kitten and we are best of friends!
In my investigations of the ThermoTime, ColdStart and the AAR, I discovered that someone at some time inserted a sawed off bolt into the air hose connecting the AAR to the S boot that sealed it-allowing NO AIR FLOW. I removed it, remade the wire harness for the cold start system, tested all components (visually, electronically and mechanically) and they all passed and work properly.
During this process, I did read your AAR description and remedy for more air. I chose not to do it because I figured removing the bolt would solve the problem. It did not. So perhaps next step is to adjust the AAR to open more?

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Amskeptic
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Re: Hard cold start

Post by Amskeptic » Fri Oct 16, 2015 8:10 am

VWinVT wrote:EFM-If the screw is loose for the wiper, then yes, I can move it freely and independently of the cog's input. Once the screw is seated, when I move the wiper, the cog spring responds accordingly.
Well, any movement of the wiper winds up the spring. That is normal. When the wiper is adjusted and clamped down, it is one with the vane in the AFM, the vane is resisted by the spring, any movement of the wiper is also moving the vane against the spring tension . . . .
VWinVT wrote: When I turn the key, the motor 'catches' instantly. If I do not give it one quick shot of gas pedal, it will die. After the quick shot of gas pedal, it will idle on its own...albeit a bit lumpy and chuggy. After 4-5 minutes, she purrs like a kitten and we are best of friends!
Good enough.
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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