 No idle - '74 2.0l FI |
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| watsonrx13 |
 Jan 17 2011, 06:55 AM
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Advanced Member  Group: Members Posts: 2,735 Joined: 18-February 03 From: Plant City, FL Member No.: 312 Region Association: South East States  |
Since I've rebuilt my '74 2.0l FI engine I've had problems with the car not idling. After it warms up it dies. I've set the timing to 27 and the dwell is at 46. I tried adjusting the ECU knob and the air idle screw but neither appear to have any effect on the idle. When I adjust the knob I can feel it click. I counted 21 total clicks. The engine runs great above idle. The injectors have been rebuilt, new AA vacuum hoses replaced, all gaskets are new.
Can the ECU be taken apart and cleaned? Does anyone have a pic of the ECU opened up showing the knob area? Any recommendations on how to fix the idle problem I'm having? -- Rob |
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| watsonrx13 |
Jan 31 2011, 05:23 PM
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Advanced Member Group: Members Posts: 2,735 Joined: 18-February 03 From: Plant City, FL Member No.: 312 Region Association: South East States |
I was finally able to work on the car this weekend. I'm still having problems with the engine not idling, hot or cold. I took the car out for a quick drive and didn't have any issues except when I stopped.
I went by after work and checked the following. After reinstalling the AAR I wasn't able to start the car at all now. Here are the components that I checked: 1. MSP - I pumped it up to 20hg. I checked it again in 5 min and it was at 17hg. 2. I removed the AAR and hooked it up to a 12v power supply. At the end of 10 min it had heated up and the valve had closed. 3. I checked the CHT when it was cold but only got a reading of 1, regardless of the ohm settitng. After the car was warmed up I disconnected the CHT and hooked a wire directly to ground, which seemed to help. 4. I reset the TPS as suggested above. 5. All of the vacuum hoses are new and tight. 5. All of the seals are new. What components make up the idle circuit? It appears that something is telling the ECU that the motor is not running and therefore no fuel is being injected when in the idle mode. Here are some pics of the vacuum lines, does anyone see anything wrong? BTW I used AA's vacuum hose diagram.     -- Rob |
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| Spoke |
Feb 1 2011, 10:55 AM
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#3
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Jerry Group: Members Posts: 7,436 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None 
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QUOTE(watsonrx13 @ Jan 31 2011, 06:23 PM)  I took the car out for a quick drive and didn't have any issues except when I stopped. It would seem that if the CHT sender was bad that it would affect the running of the engine at all RPMs, not just idle. I believe the CHT sets the pulse width of the injectors throughout the entire RPM range. If the CHT sender was truly zero ohms, the car shouldn't run. |
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Posts in this topic
watsonrx13 No idle - '74 2.0l FI Jan 17 2011, 06:55 AM
gasman First check that the AAR is fully closed when warm... Jan 17 2011, 10:11 AM r_towle I would agree that something else it wrong.
The kn... Jan 17 2011, 10:16 AM Jeffs9146
Check your CHTS (Cylinder Head Temp Sensor) This... Jan 17 2011, 10:20 AM jsayre914 Vacume leak?? Check all the hoses are tight and ma... Jan 17 2011, 11:33 AM watsonrx13 So if I read Brad website correctly I need a 0 280... Jan 17 2011, 11:57 AM
Krieger
So if I read Brad website correctly I need a 0 28... Jan 17 2011, 12:27 PM messix oil fill cap not tight? Jan 17 2011, 01:15 PM r_towle Here is how I go about this...and it works.
Unplug... Jan 17 2011, 02:24 PM SLITS Make sure the knob is in the middle of the range .... Jan 17 2011, 08:26 PM detoxcowboy
Since I've rebuilt my '74 2.0l FI engine ... Jan 18 2011, 12:23 AM detoxcowboy I also have a 74 2.0, :agree: there is another pr... Jan 18 2011, 11:07 AM sfrenck
I was finally able to work on the car this weeken... Jan 31 2011, 06:12 PM detoxcowboy
I took the car out for a quick drive and didn... Feb 1 2011, 11:33 AM watsonrx13 more pics..
Here's how I tested the AAR..... Jan 31 2011, 05:24 PM Jeffs9146 I still vote for CHTS!!!! Jan 31 2011, 05:51 PM detoxcowboy CHT Value and issue,
Function: Senses engine tem... Jan 31 2011, 06:19 PM watsonrx13 Thanks guys. I also believe it appears to be a pro... Jan 31 2011, 07:19 PM Jeffs9146
It is not hard but be very carefull not to cross... Jan 31 2011, 07:43 PM underthetire
It is not hard but be very carefull not to cros... Feb 1 2011, 10:04 AM brenz
It is not hard but be very carefull not to cros... Feb 1 2011, 11:34 AM Spoke One simple test you can do to make sure your CHT i... Feb 1 2011, 05:58 AM detoxcowboy 74 2.0 does not use the "missing" advanc... Feb 1 2011, 08:11 AM detoxcowboy From the link I posted further up this post..
Th... Feb 1 2011, 11:31 AM watsonrx13 OK guys the engine started right up and is now idl... Feb 1 2011, 04:46 PM Jeffs9146 :first: :first: :first: :first:
I win!... Feb 1 2011, 07:02 PM detoxcowboy :hard: done, It's over! Congrats! CHT ... Feb 1 2011, 07:57 PM |
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