Greg 85 Posted April 20, 2020 Author Share Posted April 20, 2020 Greg, I'm going to ask if you've checked the FPR? Do you have (see or smell) any fuel in the vacuum hose? 1200 rpm. idle doesn't sound like no fuel pressure. It also doesn't seem like it could be caused by a failing ignition component. Seems more like a flakey IAC. But I haven't got my hands on the truck. Maybe the computer is damaged? Have you inspected the board for scorches or leaking Caps? IAC is new ad well as just about every electrical part on the truck.😂😂😂 Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted April 20, 2020 Share Posted April 20, 2020 Greg, I'm going to ask if you've checked the FPR? Do you have (see or smell) any fuel in the vacuum hose? 1200 rpm. idle doesn't sound like no fuel pressure. It also doesn't seem like it could be caused by a failing ignition component. Seems more like a flakey IAC. But I haven't got my hands on the truck. Maybe the computer is damaged? Have you inspected the board for scorches or leaking Caps? IAC is new ad well as just about every electrical part on the truck.😂😂😂 Have you considered an exorcism? Link to comment Share on other sites More sharing options...
Greg 85 Posted April 20, 2020 Author Share Posted April 20, 2020 Have you considered an exorcism? It has been a nightmare that seems, looking back, to have stemmed from the electrical searching for ground, having poor grounds and overheated grounds caused alot of issues in different systems.once I got the grounds fixed next was all the individual issues causef by poor ground and believe that the ecm went with or along with everything else. But today I was able to prove the issue for the first time an seen the results and they are good!😁I think I see a light at the end of the tunnel! Link to comment Share on other sites More sharing options...
Gary Lewis Posted April 20, 2020 Share Posted April 20, 2020 Have you considered an exorcism? It has been a nightmare that seems, looking back, to have stemmed from the electrical searching for ground, having poor grounds and overheated grounds caused alot of issues in different systems.once I got the grounds fixed next was all the individual issues causef by poor ground and believe that the ecm went with or along with everything else. But today I was able to prove the issue for the first time an seen the results and they are good!😁I think I see a light at the end of the tunnel! Excellent! When/if you decide it is time for a new ECM, let's find the right part number. And the easiest way to do that is if you have a sticker, usually on the passenger's side valve cover, that gives the calibration code. If not, we can usually figure it out. And, if you are pulling the ECM it should have info on it that will help. But, it is likely that several different ECM's were used. Link to comment Share on other sites More sharing options...
Greg 85 Posted April 29, 2020 Author Share Posted April 29, 2020 Excellent! When/if you decide it is time for a new ECM, let's find the right part number. And the easiest way to do that is if you have a sticker, usually on the passenger's side valve cover, that gives the calibration code. If not, we can usually figure it out. And, if you are pulling the ECM it should have info on it that will help. But, it is likely that several different ECM's were used. I have pulled the ECM, and between the ECM #'s, calibration code and VIN I was able to order one through my local parts house. Side note Pin #22 the problem child came out with the plug along with 5 other pins out of the ECM. Defiantly could be the reason I was having so many different issues. Is this common for pins to break loose from the ECM and be stuck in the plug? I should have my ECM in a few days and I still need to fish out the broken pins from the plug but hope and pray that this is the final piece to the puzzle. I am also going to pull the IC and replace all the bulbs for the warning lights as I think that is why I could not get flash codes. I feel this is near the end of the saga that is Black Beauty electrical nightmare! Link to comment Share on other sites More sharing options...
Gary Lewis Posted April 29, 2020 Share Posted April 29, 2020 Excellent! When/if you decide it is time for a new ECM, let's find the right part number. And the easiest way to do that is if you have a sticker, usually on the passenger's side valve cover, that gives the calibration code. If not, we can usually figure it out. And, if you are pulling the ECM it should have info on it that will help. But, it is likely that several different ECM's were used. I have pulled the ECM, and between the ECM #'s, calibration code and VIN I was able to order one through my local parts house. Side note Pin #22 the problem child came out with the plug along with 5 other pins out of the ECM. Defiantly could be the reason I was having so many different issues. Is this common for pins to break loose from the ECM and be stuck in the plug? I should have my ECM in a few days and I still need to fish out the broken pins from the plug but hope and pray that this is the final piece to the puzzle. I am also going to pull the IC and replace all the bulbs for the warning lights as I think that is why I could not get flash codes. I feel this is near the end of the saga that is Black Beauty electrical nightmare! Sure glad you were able to find one. Just getting the number is sometimes difficult, but finding a replacement has proven hard for some. I don't think it is common for the pins to break loose. I have several ECMs and none of the pins were loose when I pulled them. But I do think this has to be a big part of your problem. Let's hope it solves all of them. Link to comment Share on other sites More sharing options...
71_badmach Posted June 5, 2020 Share Posted June 5, 2020 Excellent! When/if you decide it is time for a new ECM, let's find the right part number. And the easiest way to do that is if you have a sticker, usually on the passenger's side valve cover, that gives the calibration code. If not, we can usually figure it out. And, if you are pulling the ECM it should have info on it that will help. But, it is likely that several different ECM's were used. I have pulled the ECM, and between the ECM #'s, calibration code and VIN I was able to order one through my local parts house. Side note Pin #22 the problem child came out with the plug along with 5 other pins out of the ECM. Defiantly could be the reason I was having so many different issues. Is this common for pins to break loose from the ECM and be stuck in the plug? I should have my ECM in a few days and I still need to fish out the broken pins from the plug but hope and pray that this is the final piece to the puzzle. I am also going to pull the IC and replace all the bulbs for the warning lights as I think that is why I could not get flash codes. I feel this is near the end of the saga that is Black Beauty electrical nightmare! Hello, I was browsing the thread and hope you resolved the issue with the ECM. I thought it was amazing that you could order a replacement for a 35 year old truck. BTW, I also have an 85 with the EFI, and was considering going back to a carb setup. My issue was ignition problems, and some strange electrical issues. Dave Link to comment Share on other sites More sharing options...
Greg 85 Posted June 6, 2020 Author Share Posted June 6, 2020 Hello, I was browsing the thread and hope you resolved the issue with the ECM. I thought it was amazing that you could order a replacement for a 35 year old truck. BTW, I also have an 85 with the EFI, and was considering going back to a carb setup. My issue was ignition problems, and some strange electrical issues. Dave The problem still exist. However I know what is happening now, just don't know why. Link to comment Share on other sites More sharing options...
Greg 85 Posted June 7, 2020 Author Share Posted June 7, 2020 Sure glad you were able to find one. Just getting the number is sometimes difficult, but finding a replacement has proven hard for some. I don't think it is common for the pins to break loose. I have several ECMs and none of the pins were loose when I pulled them. But I do think this has to be a big part of your problem. Let's hope it solves all of them. Okay, so still did not fix the issue with loosing ground although the length of time has lengthened before it loses ground. Okay so I know it is losing ground at the fuel pump shut off relay. When it loses it I can add an external ground and the truck will start right up, remove the ground and sometimes it will stay running other times it'll die. Any thoughts? Link to comment Share on other sites More sharing options...
Greg 85 Posted June 8, 2020 Author Share Posted June 8, 2020 That's a bit more complex, but not too bad. I'd start through the system inch by inch, starting at the tank selector valve/switch. If that doesn't work you won't get voltage to the pump. And they are a known problem. http://forum.garysgaragemahal.com/file/n55172/1985-etm-page104_1.jpg Gary, is it possible to get pages 60 and 62 for the YY and ZZ wires for the fuel pump cutoff relay on both 85 and 86 years? Link to comment Share on other sites More sharing options...
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