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No Start Problem

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Old 04-19-2022, 07:35 PM
  #76  
harveyf
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If the tach is bouncing just a bit, that is a good sign.
Like I said before, get a helper and do some of the checks.
1) Will it run with gas or starting fluid squirted into the AFM
2) Do you feel the injectors pulsing?
3) Do you get a spark out of each plug when having them out and grounded?
4) Have you confirmed beyond the shadow of a doubt that your firing order is correct? (I had a friend in high school that spent 4 months trying to get a MGA started. I switched the leads to the correct positions and it started right up).
Old 04-19-2022, 07:46 PM
  #77  
Acantor
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The firing order is correct starting with 1 being on the bottom right and then following the pattern on the cam housing
Old 04-19-2022, 07:51 PM
  #78  
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To be thorough, you need to establish the compression stroke on Cyl #1, pull the distributor cap, and make sure the rotor is pointing towards the wire going to #1. From there, you can follow the pattern on the cam housing.
To confirm the compression stroke, at a minimum, check the timing mark in the window at the back of the head. Better is to have the spark plug inserted loosely and listen for the air being forced past it as you rotate the engine by hand.
Old 04-19-2022, 07:59 PM
  #79  
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Originally Posted by harveyf
To be thorough, you need to establish the compression stroke on Cyl #1, pull the distributor cap, and make sure the rotor is pointing towards the wire going to #1. From there, you can follow the pattern on the cam housing.
To confirm the compression stroke, at a minimum, check the timing mark in the window at the back of the head. Better is to have the spark plug inserted loosely and listen for the air being forced past it as you rotate the engine by hand.
I did that when I was rebuilding the engine. I got everything to tdc then I put on the rotor and saw that it was to the down right position. I then followed the pattern 1-3-4-2 starting with one where the rotor was pointing since it was at tdc.
Old 04-19-2022, 08:02 PM
  #80  
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I am convinced that it is an air issue since that is the only thing that I have changed (besides a cam) since the car was running.
Old 04-19-2022, 08:54 PM
  #81  
T&T Racing
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Originally Posted by Acantor
I am convinced that it is an air issue since that is the only thing that I have changed (besides a cam) since the car was running.
Have you separated the J boot from the AFM and sprayed fuel into the J boot while another person cranks the engine to see if it starts and continues to run while spraying fuel in?
Old 04-19-2022, 09:17 PM
  #82  
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Originally Posted by T&T Racing
Have you separated the J boot from the AFM and sprayed fuel into the J boot while another person cranks the engine to see if it starts and continues to run while spraying fuel in?
I was going to do this when I have someone to help me. I am getting two different suggestions, do I spray it into the AFM or do I spray it after the AFM.
Old 04-19-2022, 10:00 PM
  #83  
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Well, i'll defer to Tom but to me it shouldn't make any difference. Into the AFM is easier, as all you have to do is remove the cover off the air filter (and the filter itself).
Old 04-19-2022, 10:58 PM
  #84  
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I think that doing it after the AFM might be more conclusive because there will be bore fluid being sucked in as opposed to some getting trapped in the AFM. I think I will be able to take the j boot off the AFM just enough to spray some fluid in, and I will not have to remove anything.
Old 04-20-2022, 12:45 PM
  #85  
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Originally Posted by harveyf
Well, i'll defer to Tom but to me it shouldn't make any difference. Into the AFM is easier, as all you have to do is remove the cover off the air filter (and the filter itself).
At the Filter. More time delay before the fuel vapor/droplets make it to the intake. At the J boot, best place.
Old 04-20-2022, 07:35 PM
  #86  
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@T&T Racing I just resistance tested the speed and reference sensors. Fron pin 8-27 I read around 1k ohms, but for pin 8-23, I either read infinite or didn't seem to get anything (clarks garage says that it should be greater than 1k ohms). I did the same for the reverence sensor and got the same results (1000ohms for 25-26 and nothing/infinite for 25-78).

Also throttle position sensor is good.

Last edited by Acantor; 04-20-2022 at 07:39 PM.
Old 04-20-2022, 07:57 PM
  #87  
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Originally Posted by Acantor
@T&T Racing I just resistance tested the speed and reference sensors. Fron pin 8-27 I read around 1k ohms, but for pin 8-23, I either read infinite or didn't seem to get anything (clarks garage says that it should be greater than 1k ohms). I did the same for the reverence sensor and got the same results (1000ohms for 25-26 and nothing/infinite for 25-78).

Also throttle position sensor is good.
sounds good as per the sensors except do not know if any metal chips on speed sensor. Hold off checking until you do other tests.
Old 04-20-2022, 08:00 PM
  #88  
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Originally Posted by T&T Racing
sounds good as per the sensors except do not know if any metal chips on speed sensor. Hold off checking until you do other tests.
ok will do. I plan on testing with the starting fluid this weekend, so If you think of any other tests please let me know.
Old 04-22-2022, 08:04 PM
  #89  
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Ok update time. I performed the starting fluid test and with me spraying the fluid through a crack in the j boot (just after the AFM), the car was able to run. As expected it died when I stopped spraying. I think that this points out that I still have a vacuum leak due to thorough testing of the fuel system. I still don't know quite where it is coming from as far as a specific connection, but I will be taking everything apart again and putting clamps on junctures that don't have any (they don't have any because the t junction that I used is not meant for clamps)
Old 04-23-2022, 08:34 AM
  #90  
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Originally Posted by Acantor
Ok update time. I performed the starting fluid test and with me spraying the fluid through a crack in the j boot (just after the AFM), the car was able to run. As expected it died when I stopped spraying. I think that this points out that I still have a vacuum leak due to thorough testing of the fuel system. I still don't know quite where it is coming from as far as a specific connection, but I will be taking everything apart again and putting clamps on junctures that don't have any (they don't have any because the t junction that I used is not meant for clamps)
Acantor,
The sensors are 👌

It would be wise to check for vacuum leaks to be sure to assure yourself that vacuum leaks are not the problem.

Then retest with starter fluid and seek if you get the same results as your latest post. If so, go to next step of testing

THEN, on to the fuel injection system which I believe is the root cause. Refer my post on how to test the functioning of the fuel injection system. Eventhough the fuel injectors were cleaned and tested and could be assumed OK, the system also has an electrical component. The test should discover issues.

Last edited by T&T Racing; 04-23-2022 at 09:09 AM.


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