85"720 Posted November 6, 2022 Report Share Posted November 6, 2022 I'm having trouble with my truck. Truck is running pretty bad. First problem i found was The wires at the connector for my carburetor was messed up and causing an intermediate connection. I cut the connector off and rewired each wire to the other side. The thing that I noticed was that 2 wires are the same color, red/yellow and on the opposite side of them are 2 white wires. I think I have these wired correctly but I'm not 100% sure. Do these wires make any difference being crossed with the wrong white wire?? 1 Quote Link to comment
85"720 Posted November 7, 2022 Author Report Share Posted November 7, 2022 58 minutes ago, 85"720 said: I'm having trouble with my truck. Truck is running pretty bad. First problem i found was The wires at the connector for my carburetor was messed up and causing an intermediate connection. I cut the connector off and rewired each wire to the other side. The thing that I noticed was that 2 wires are the same color, red/yellow and on the opposite side of them are 2 white wires. I think I have these wired correctly but I'm not 100% sure. Do these wires make any difference being crossed with the wrong white wire?? 1 Quote Link to comment
datzenmike Posted November 7, 2022 Report Share Posted November 7, 2022 Looks like the RY (red/yellow) go to one white and the other is the R (red) anti dieseling solenoid. Listen near the carburetor while someone turns the ignition between off and on several times. (not start) What you should hear id the anti dieseling solenoid is wired correctly is a soft clicking sound. If you do... it's wired correctly. BTW the 720 6 wire plug IS problematic for intermittent contact. The harness should have been longer to take the strain off the wires. 1 Quote Link to comment
85"720 Posted November 7, 2022 Author Report Share Posted November 7, 2022 11 minutes ago, datzenmike said: Looks like the RY (red/yellow) go to one white and the other is the R (red) anti dieseling solenoid. Listen near the carburetor while someone turns the ignition between off and on several times. (not start) What you should hear id the anti dieseling solenoid is wired correctly is a soft clicking sound. If you do... it's wired correctly. BTW the 720 6 wire plug IS problematic for intermittent contact. The harness should have been longer to take the strain off the wires. Im pretty sure I have it wired correctly. Yes I do hear the clicking sound when the key is on run/engine off. Yeah I've heard alot about the harness wires being too short causing problems. I have it back together now and it still runs pretty bad. 1 Quote Link to comment
datzenmike Posted November 7, 2022 Report Share Posted November 7, 2022 Because a solenoid is used to adjust the primary jet any sensor failure could cause an extreme lean condition that could harm the engine so the ECU sets it on an over rich default 'limp home' mode. Mileage and performance will be terrible. Another often overlooked cause of poor running is the exhaust side coil not firing. It's not the coil. Check for spark on both intake and exhaust sides. 1 Quote Link to comment
85"720 Posted November 7, 2022 Author Report Share Posted November 7, 2022 34 minutes ago, datzenmike said: Because a solenoid is used to adjust the primary jet any sensor failure could cause an extreme lean condition that could harm the engine so the ECU sets it on an over rich default 'limp home' mode. Mileage and performance will be terrible. Another often overlooked cause of poor running is the exhaust side coil not firing. It's not the coil. Check for spark on both intake and exhaust sides. Yeah its definitely running rich. Sometimes it would backfire when trying to accelerate. Checked for vacuum leaks already and didn't find any. I need to confirm if exhaust coil is working. I pulled the first fuse on the left and it killed the motor. Without the fuse the car runs worse and with it is acts a lil bit better. 1 Quote Link to comment
85"720 Posted November 13, 2022 Author Report Share Posted November 13, 2022 Just a little update. I checked to see if exhaust side is firing and it is except for #3 plug wire. Swapped Plug wire around and confirmed its dead. Didn't have time to change it out yet but do you think it will make it run really bad with that one wire dead?? Truck sat for like a week and noticed that it didn't fast idle when I started it today. It just ran like it has been started already? Quote Link to comment
datzenmike Posted November 13, 2022 Report Share Posted November 13, 2022 The other plug would have fired that cylinder but because only one plug that cylinder would have acted like the timing was retarded. It would not make a significant difference. A dead plug wire is indicative that all the other wires may be in need of replacing as well as the rotor and distributor cap. Do NOT replace the coils, they never go bad, and the replacements will be of inferior quality. You would as likely as not be putting a bad coil in. Pull and look at the plugs, they are usually replaced by visually checking them for wear. ONLY NGK plugs, BPR6ES for the intake side and BPR5ES for the intake. Do NOT but them from Amazon.... too many counterfeit parts there. Quote Link to comment
85"720 Posted November 13, 2022 Author Report Share Posted November 13, 2022 50 minutes ago, datzenmike said: The other plug would have fired that cylinder but because only one plug that cylinder would have acted like the timing was retarded. It would not make a significant difference. A dead plug wire is indicative that all the other wires may be in need of replacing as well as the rotor and distributor cap. Do NOT replace the coils, they never go bad, and the replacements will be of inferior quality. You would as likely as not be putting a bad coil in. Pull and look at the plugs, they are usually replaced by visually checking them for wear. ONLY NGK plugs, BPR6ES for the intake side and BPR5ES for the intake. Do NOT but them from Amazon.... too many counterfeit parts there. Yeah I bought all new wires ngk spark plugs, the cap and rotor. I'll be putting these on sometime this week. Quote Link to comment
datzenmike Posted November 14, 2022 Report Share Posted November 14, 2022 That should eliminate electrical leaving carburetor. Quote Link to comment
85"720 Posted November 14, 2022 Author Report Share Posted November 14, 2022 1 hour ago, datzenmike said: That should eliminate electrical leaving carburetor. Had the carb professional rebuilt 2 years ago and it ran flawless. I hope it's not that again 🙃 Quote Link to comment
datzenmike Posted November 14, 2022 Report Share Posted November 14, 2022 The ECC carburetor relies on several sensor inputs so the ECU can generate a mixture. Quote Link to comment
85"720 Posted November 14, 2022 Author Report Share Posted November 14, 2022 13 hours ago, datzenmike said: The ECC carburetor relies on several sensor inputs so the ECU can generate a mixture. Which sensors does it require?? Quote Link to comment
85"720 Posted November 21, 2022 Author Report Share Posted November 21, 2022 Giving an update. I did spark plugs, wires, cap and rotor and now the truck is running great. Quote Link to comment
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