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> Car just dies, Then hard to start and won't idle
Black22
post Oct 27 2012, 03:10 PM
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Just started happening yesterday.

Car was running fine and I had my AFM rebulit by Fuel Injection Corp. I had it rebuilt because I was fiddling around and drive the car before warming it up. At the first stop sign I took off and and had a lean backfire. Car still ran but the A/F mixture was all over the map at any given speed or stoplight.

Anyways, installed the AFM. Started the car up and let it warm up while I wiped the car down. My intention was to warm it up and then set the idle mixture. Car warmed up and the idle mix was a hair off so I didn't touch it.

All of the sudden the car just shuts down! As if I'd turned he keys off! Tried to start it and it was very hard to start. It won't idle, it will just shut down. I can keep the car running if I keep my foot on the accelerator. It is missing badly and running very rich.

If I let it sit for 10-15 minutes and cool down it will fire up just perfectly . It will run fine until it decides to shut down again!

Here's what I've replaced so far with new or spare parts

Coil
Points /condenser
Cap/ rotor
Cleaned and inspected spark plugs (good)
FI dual relay
FI brain
Ohmed out CHTS ( 2400 cold / 50 hot)

What am I missing?

Engine is 1911 with stock L-jet

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benalishhero
post Oct 27 2012, 03:24 PM
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Maybe you ripped the intake boot. (IMG:style_emoticons/default/confused24.gif)
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timothy_nd28
post Oct 27 2012, 03:31 PM
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Can you duplicate these problems everytime you start the car?
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silver74insocal
post Oct 27 2012, 03:37 PM
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QUOTE(timothy_nd28 @ Oct 27 2012, 02:31 PM) *

Can you duplicate these problems everytime you start the car?


(IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/popcorn[1].gif)
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Black22
post Oct 27 2012, 03:38 PM
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Boot is good.

Tim: every time. (IMG:style_emoticons/default/sad.gif)
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timothy_nd28
post Oct 27 2012, 03:44 PM
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The fact that your engine continues to run when depressing the throttle, confirms that your fuel delivery is working fine. But when idling, can you verify that the AFM wiper arm isn't pushing against the fuel contacts, thus turning off your fuel pump?
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steuspeed
post Oct 27 2012, 03:45 PM
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It's usually the LAST thing you or somone else worked on or changed before the problem started. I would retrace your steps backwards. You may need to re-install the old parts to find the issue.
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Black22
post Oct 27 2012, 03:50 PM
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QUOTE(steuspeed @ Oct 27 2012, 02:45 PM) *

It's usually the LAST thing you or somone else worked on or changed before the problem started. I would retrace your steps backwards. You may need to re-install the old parts to find the issue.


Only thing changed directly before problem started is he AFM.

The rest was changed to solve problem. One piece at a time.
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Black22
post Oct 27 2012, 03:54 PM
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QUOTE(steuspeed @ Oct 27 2012, 02:45 PM) *

It's usually the LAST thing you or somone else worked on or changed before the problem started. I would retrace your steps backwards. You may need to re-install the old parts to find the issue.


The last thing I wanted to do was to open the new rebuilt AFM...voiding warranty!

But I'm a rebel and did it anyways...all is good in there. I can move contacts for fuel pump and it will slowly die of fuel starvation.

My problem is as if someone shuts the key off. Instant off!
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Black22
post Oct 27 2012, 03:58 PM
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Just on a whim I pulled the Cylinder head temp sensor while car was running...it died instantly just like my problem.

Even thought it ohm'd out in spec, it could have intermitant problems...right?
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timothy_nd28
post Oct 27 2012, 04:01 PM
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QUOTE(Black22 @ Oct 27 2012, 01:58 PM) *

Just on a whim I pulled the Cylinder head temp sensor while car was running...it died instantly just like my problem.

Even thought it ohm'd out in spec, it could have intermitant problems...right?



Not likely, resistors aren't intermittent. Since this problem is repeatable like clock work, put your voltmeter on (+) side of the ignition coil, and see if the 12vdc drops to 0. when your engine dies.
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Black22
post Oct 27 2012, 04:04 PM
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Just happen as I was reading your response Tim.
Car died. Holding for results. Disregard last numbers posted
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Black22
post Oct 27 2012, 04:15 PM
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11.18 volts at coil when car dies.
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timothy_nd28
post Oct 27 2012, 04:20 PM
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So your not losing the spark and your fuel pump is staying active during idle, its saying AFM, well atleast for me it is.
You had your AFM dialed in earlier, can't remember but 6-10 turns? Do you think this rebuilder reset the wheel?
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Black22
post Oct 27 2012, 04:37 PM
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Oh yeah, this is a comeplety different unit.
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timothy_nd28
post Oct 27 2012, 04:39 PM
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This means nothing, but I own 2 AFM's. The older AFM is the one I currently use on my car, and the wheel has been adjusted for my 1911. It idles fine, and has pretty good HP, as I set it to run slightly rich. With all of this done, I still get 31 mpg.
The other AFM I own is brand new, well NOS, still has a plastic blue cap on it. For shits and giggles, I decided to try it out. This virgin AFM ran poor on my engine. I could easily keep it running, by reving the engine, but it would die if let to idle. I kinda remember it being like it was a "key off" situation, but its been too long for me to be 100% certain.

Do you have a spare AFM laying around, even if it is broken?
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Black22
post Oct 27 2012, 05:25 PM
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QUOTE(timothy_nd28 @ Oct 27 2012, 03:39 PM) *

This means nothing, but I own 2 AFM's. The older AFM is the one I currently use on my car, and the wheel has been adjusted for my 1911. It idles fine, and has pretty good HP, as I set it to run slightly rich. With all of this done, I still get 31 mpg.
The other AFM I own is brand new, well NOS, still has a plastic blue cap on it. For shits and giggles, I decided to try it out. This virgin AFM ran poor on my engine. I could easily keep it running, by reving the engine, but it would die if let to idle. I kinda remember it being like it was a "key off" situation, but its been too long for me to be 100% certain.

Do you have a spare AFM laying around, even if it is broken?

No spare right now...was going to pick one up at the G&R swamped tomorrow.
I want to drive the teener there to verify I was good. Now I'll just buy one and hope!

I'll have to give Fuel Injection Corp. a call on Monday and let them know its not working.
That was $200 not well spent! (IMG:style_emoticons/default/headbang.gif)
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timothy_nd28
post Oct 27 2012, 05:28 PM
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With the car running, can you physically move the wiper to a optimum position, with the car at idle. Does it stay running any better with you acting as Mr. AFM?
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Black22
post Oct 27 2012, 05:35 PM
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QUOTE(timothy_nd28 @ Oct 27 2012, 04:28 PM) *

With the car running, can you physically move the wiper to a optimum position, with the car at idle. Does it stay running any better with you acting as Mr. AFM?


No. It dies when it thinks it is time to die. Wait 5 minutes after it dies and it will start and run perfectly another 5 minutes. If you try to start it immediately after it dies, it is very hard to start and runs poorly. Misses and runs very rich...most likely due the missing and fuel not being burned.

In the morning it will idle for 15-20 minutes before dying. It seems to be heat related. Something is telling the system to shut down.
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timothy_nd28
post Oct 27 2012, 06:11 PM
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I think your right, too much fuel
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