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Engine misfire, need new pcm?

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  #11  
Old 10-30-2015 | 11:03 AM
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Originally Posted by Lesmyer
It could be that your remaining problem might be the CMP retard setting and/or distributor gear wear aggravated by a less than optimal distributor cap. New distributor cap could potentially temporarily cover up a problem, only to have it come back in a little while (or the new cap could truly be the cause - IMHO doubtful) - but it's all pure speculation without solid testing.

However, you have told me that the spark plug was black with carbon so we are going to begin with the fuel system, even if it looks difficult to do. Usually people take one look at the fuel tests and immediately start trying to avoid doing all of them by latching on to anything else they come across. Just know there is a lot of unsubstantiated misinformation out there.

Do the fuel system tests and report. We're not going to play the typical guessing games based on a someone said replacing this part fixed his. Diagnosis needs to be logical and complete - otherwise I'm out and don't intend to waste my time trying to drag you back on track. Fair enough?
I was told that my old distributor cap was pretty burnt on the inside I don't know if that points to anything. Like a fuel system problem. I'm just trying to give you guys all the information I can.
 
  #12  
Old 10-30-2015 | 11:11 AM
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Originally Posted by Lesmyer
It could be that your remaining problem might be the CMP retard setting and/or distributor gear wear aggravated by a less than optimal distributor cap. New distributor cap could potentially temporarily cover up a problem, only to have it come back in a little while (or the new cap could truly be the cause - IMHO doubtful) - but it's all pure speculation without solid testing.

However, you have told me that the spark plug was black with carbon so we are going to begin with the fuel system, even if it looks difficult to do. Usually people take one look at the fuel tests and immediately start trying to avoid doing all of them by latching on to anything else they come across. Just know there is a lot of unsubstantiated misinformation out there.

Do the fuel system tests and report. We're not going to play the typical guessing games based on a someone said replacing this part fixed his. Diagnosis needs to be logical and complete - otherwise I'm out and don't intend to waste my time trying to drag you back on track. Fair enough?
I was told that my old distributor cap was pretty burnt on the inside I don't know if that points to anything. Like a fuel system problem. I'm just trying to give you guys all the information I can.
 
  #13  
Old 10-30-2015 | 12:28 PM
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Originally Posted by Loganu01
I was told that my old distributor cap was pretty burnt on the inside I don't know if that points to anything. Like a fuel system problem. I'm just trying to give you guys all the information I can.
Sigh..... You was also told your PCM was the problem.

From my first post in your thread...... "Also suspect is the ignition system (because of your comments about cap fixing some misfires) , but in your case I believe you should start with the fuel system and competely verify its operation before moving on. Note no parts replacement required to do this verification! Just work!"

You are not comprehending my strategy, are not listening, and clearly don't want to do as I am advising.

I'm out. Someone else want to help Loganu01? There are certainly other qualified people here that can.
 

Last edited by LesMyer; 10-30-2015 at 12:36 PM.
  #14  
Old 10-30-2015 | 12:42 PM
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Originally Posted by Lesmyer
Sigh..... You was also told your PCM was the problem.

From my first post in your thread...... "Also suspect is the ignition system (because of your comments about cap fixing some misfires) , but in your case I believe you should start with the fuel system and competely verify its operation before moving on. Note no parts replacement required to do this verification! Just work!"

You are not comprehending my strategy, are not listening, and clearly don't want to do as I am advising.

I'm out. Someone else want to help Loganu01? There are certainly other qualified people here that can.
I am comprehending your strategy, and I was going to do as you advised. I am going to get the fuel gauge after work today, and run the tests. I was just trying to make sure I said everything I was told so nothing was missed.
 
  #15  
Old 10-30-2015 | 01:28 PM
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Originally Posted by Loganu01
I am comprehending your strategy, and I was going to do as you advised. I am going to get the fuel gauge after work today, and run the tests. I was just trying to make sure I said everything I was told so nothing was missed.
Have you read through the fuel pressure diagnosis thread yet? There is more than a fuel pressure gauge needed. You need to come up with some fittings to adapt to the fuel filter. For you, these are the important tests that cannot be omitted like your "mechanic" did. Screwing on the fuel pressure gauge and starting the vehicle tests very little. FYI you need to dead-end the fuel system and watch max fuel pressure as well as time for pressure to bleed down in different situations.

Looking for the following 4 numbers:
1) Pressure reading at service port with engine off and pump energized
2) Leakdown test - entire system
3) Max fuel pump output pressure
4) Pump-only leakdown test (after max output pressure)

I'll be here when you get the tests done and post the results.
 

Last edited by LesMyer; 10-30-2015 at 01:50 PM.
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