Fuel sync problems
#11
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Adam Sorensen (01-10-2022)
#15
Oh boy, I think you made a big boo-boo. I'll try to talk you thru it.
I have a MT2500 so I'm pretty familiar with it. You need a Domestic Cartridge that includes your year, and the 13a key. The 13 key does not function 100% correctly, it must be 13a.
There are two ways you can "see" fuel sync. One is on the all data function where you see the various voltages and inputs for all sensors as you scroll up and down with the wheel. That IS NOT the one you want. That one wanders all over to to timing advance from the pcm from various sensor input like the TPS, MAP, and O2 sensors.
The one you want is in the engine diagnostic section. I'm sorry I don't have my scanner in front of me to see the exact pathway. This test will instantly raise your idle rpm to 992 rpms (effectively 1000rpms) and hold it there to get rid of valve train fluctuation at idle. This is the test you want to use!
Be aware that if you get the disty twisted too far out of wack (+/- 15*), you will lose fuel sync and get a code for the cam or crank sensor. That's what likely happened.
Try to set the mounting ears of the disty cap (the screw mounts that the cap screws into on the actual distributor body, one is square and one is rounded) to about 3:15 and 9:15 o'clock to get you ballpark correct and then dial it in using the correct test. IIRC, square side goes on the left toward the center of the engine. Pay attention to the ears, otherwise you'll be 180* out of sync.
If you get it set correctly and the sync is still "walking" on you, you need to pull the disty and inspect the cam gear driveshaft, the oil pump driveshaft, and the mounting post of the disty to see if it got chewed up somehow. also look at the cam position sensor (also called the pick up sensor in the disty, round plate with the cord coming off of it sitting between the disty and the disty cap, yes it's removable!) Try replacing that if your sure everything is in order.
Good luck with it!
I have a MT2500 so I'm pretty familiar with it. You need a Domestic Cartridge that includes your year, and the 13a key. The 13 key does not function 100% correctly, it must be 13a.
There are two ways you can "see" fuel sync. One is on the all data function where you see the various voltages and inputs for all sensors as you scroll up and down with the wheel. That IS NOT the one you want. That one wanders all over to to timing advance from the pcm from various sensor input like the TPS, MAP, and O2 sensors.
The one you want is in the engine diagnostic section. I'm sorry I don't have my scanner in front of me to see the exact pathway. This test will instantly raise your idle rpm to 992 rpms (effectively 1000rpms) and hold it there to get rid of valve train fluctuation at idle. This is the test you want to use!
Be aware that if you get the disty twisted too far out of wack (+/- 15*), you will lose fuel sync and get a code for the cam or crank sensor. That's what likely happened.
Try to set the mounting ears of the disty cap (the screw mounts that the cap screws into on the actual distributor body, one is square and one is rounded) to about 3:15 and 9:15 o'clock to get you ballpark correct and then dial it in using the correct test. IIRC, square side goes on the left toward the center of the engine. Pay attention to the ears, otherwise you'll be 180* out of sync.
If you get it set correctly and the sync is still "walking" on you, you need to pull the disty and inspect the cam gear driveshaft, the oil pump driveshaft, and the mounting post of the disty to see if it got chewed up somehow. also look at the cam position sensor (also called the pick up sensor in the disty, round plate with the cord coming off of it sitting between the disty and the disty cap, yes it's removable!) Try replacing that if your sure everything is in order.
Good luck with it!
The following users liked this post:
Adam Sorensen (01-10-2022)
#16
Oh boy, I think you made a big boo-boo. I'll try to talk you thru it.
I have a MT2500 so I'm pretty familiar with it. You need a Domestic Cartridge that includes your year, and the 13a key. The 13 key does not function 100% correctly, it must be 13a.
There are two ways you can "see" fuel sync. One is on the all data function where you see the various voltages and inputs for all sensors as you scroll up and down with the wheel. That IS NOT the one you want. That one wanders all over to to timing advance from the pcm from various sensor input like the TPS, MAP, and O2 sensors.
The one you want is in the engine diagnostic section. I'm sorry I don't have my scanner in front of me to see the exact pathway. This test will instantly raise your idle rpm to 992 rpms (effectively 1000rpms) and hold it there to get rid of valve train fluctuation at idle. This is the test you want to use!
Be aware that if you get the disty twisted too far out of wack (+/- 15*), you will lose fuel sync and get a code for the cam or crank sensor. That's what likely happened.
Try to set the mounting ears of the disty cap (the screw mounts that the cap screws into on the actual distributor body, one is square and one is rounded) to about 3:15 and 9:15 o'clock to get you ballpark correct and then dial it in using the correct test. IIRC, square side goes on the left toward the center of the engine. Pay attention to the ears, otherwise you'll be 180* out of sync.
If you get it set correctly and the sync is still "walking" on you, you need to pull the disty and inspect the cam gear driveshaft, the oil pump driveshaft, and the mounting post of the disty to see if it got chewed up somehow. also look at the cam position sensor (also called the pick up sensor in the disty, round plate with the cord coming off of it sitting between the disty and the disty cap, yes it's removable!) Try replacing that if your sure everything is in order.
Good luck with it!
I have a MT2500 so I'm pretty familiar with it. You need a Domestic Cartridge that includes your year, and the 13a key. The 13 key does not function 100% correctly, it must be 13a.
There are two ways you can "see" fuel sync. One is on the all data function where you see the various voltages and inputs for all sensors as you scroll up and down with the wheel. That IS NOT the one you want. That one wanders all over to to timing advance from the pcm from various sensor input like the TPS, MAP, and O2 sensors.
The one you want is in the engine diagnostic section. I'm sorry I don't have my scanner in front of me to see the exact pathway. This test will instantly raise your idle rpm to 992 rpms (effectively 1000rpms) and hold it there to get rid of valve train fluctuation at idle. This is the test you want to use!
Be aware that if you get the disty twisted too far out of wack (+/- 15*), you will lose fuel sync and get a code for the cam or crank sensor. That's what likely happened.
Try to set the mounting ears of the disty cap (the screw mounts that the cap screws into on the actual distributor body, one is square and one is rounded) to about 3:15 and 9:15 o'clock to get you ballpark correct and then dial it in using the correct test. IIRC, square side goes on the left toward the center of the engine. Pay attention to the ears, otherwise you'll be 180* out of sync.
If you get it set correctly and the sync is still "walking" on you, you need to pull the disty and inspect the cam gear driveshaft, the oil pump driveshaft, and the mounting post of the disty to see if it got chewed up somehow. also look at the cam position sensor (also called the pick up sensor in the disty, round plate with the cord coming off of it sitting between the disty and the disty cap, yes it's removable!) Try replacing that if your sure everything is in order.
Good luck with it!
Not 100% sure what cartrige and key i am useing but i well look this weekend when i home again, sure he has the right ones he got a box full of them. But when i went into the test it did bring the idle to about 1000 rpm so i am in the right spot there. My problem is after i set it and lock it down it jumps on me about a min later and also said sync is out of range and dont know why. Cam sensor about a year old had a ramdom miss fire i trying track down. Like i said befor the crank sensor is new. Guess i pull the dizzy out and see if i cant find any thing broken in there.
#17
#18
Then it's a sensor or the pcm itself causing your issue. I have had mixed results with parts store branded sensors. There seems to be a general consensus that the dealership gets a higher quality part than parts stores get. That info came from a few folks that are more in the know than I. Try a dealership crank sensor and cam sensor to see if that fixes your issue.
#19
A buddy of mine found this for me
Test Details Hotline Archive # 256645
Printer Friendly Confirmed Fix Vehicle Application: 1997 Dodge Dakota 5.2L, Vin Y, Eng Cfg V8 1998 Dodge Ram 1500 5.2L, Vin Y, Eng Cfg V8
1997 Dodge Ram 1500 5.2L, GAS, Vin Y, Eng Cfg V8 1999 Dodge Durango 5.2L, Vin Y, Eng Cfg V8
Customer Concern: The engine runs poorly. It backfires and misses.
Tests/Procedures: 1. Check the wear in the oil pump drive gear bushing by removing the distributor cap and check how much the rotor will turn back and forth. Maximum allowable is 3/16 inch at the tip.
2. If more than that, replace the bushing in the block and replace the distributor drive gear. Then set distributor sync.
3. To set sync, with the key off, rotate the engine until the TDC mark is aligned with the pointer on the front cover. Then rotate the engine an additional 17 degrees until the V8 mark on the damper aligns with the pointer on the front cover. Then loosen the hold down bolt on the distributor, connect a Digital Volt Ohm Meter (DVOM) to the Tan/Yellow (TN/YL) wire at the distributor pick-up, and rotate the distributor back and forth across the switching point of the pick-up plate. The DVOM should toggle 0.0 to 5.0 volts as the distributor crosses the switching point. Zero in on the switching point and tighten the hold down bolt for the distributor.
Potential Causes: Worn Distributor Drive Gear
Mis-Adjusted Distributor Sync
Broken Flex Plate
Worn Oil Pump Drive Gear Bushing
Tech Tips: Turning the distributor does not alter ignition timing but it does need to be in sync. The Powertrain Control Module (PCM) needs to see the Camshaft Position (CMP) sensor signal come at the expected time in relation to the Crankshaft Position (CKP) sensor.
Diagnostic Codes: None
Author: Michael Brown
Average Reported Mileage: 173255
I follow that and then recheck it with the snap on scanner and the scanner is saying it -13 off. I would of figur it be alot closer then that.
Test Details Hotline Archive # 256645
Printer Friendly Confirmed Fix Vehicle Application: 1997 Dodge Dakota 5.2L, Vin Y, Eng Cfg V8 1998 Dodge Ram 1500 5.2L, Vin Y, Eng Cfg V8
1997 Dodge Ram 1500 5.2L, GAS, Vin Y, Eng Cfg V8 1999 Dodge Durango 5.2L, Vin Y, Eng Cfg V8
Customer Concern: The engine runs poorly. It backfires and misses.
Tests/Procedures: 1. Check the wear in the oil pump drive gear bushing by removing the distributor cap and check how much the rotor will turn back and forth. Maximum allowable is 3/16 inch at the tip.
2. If more than that, replace the bushing in the block and replace the distributor drive gear. Then set distributor sync.
3. To set sync, with the key off, rotate the engine until the TDC mark is aligned with the pointer on the front cover. Then rotate the engine an additional 17 degrees until the V8 mark on the damper aligns with the pointer on the front cover. Then loosen the hold down bolt on the distributor, connect a Digital Volt Ohm Meter (DVOM) to the Tan/Yellow (TN/YL) wire at the distributor pick-up, and rotate the distributor back and forth across the switching point of the pick-up plate. The DVOM should toggle 0.0 to 5.0 volts as the distributor crosses the switching point. Zero in on the switching point and tighten the hold down bolt for the distributor.
Potential Causes: Worn Distributor Drive Gear
Mis-Adjusted Distributor Sync
Broken Flex Plate
Worn Oil Pump Drive Gear Bushing
Tech Tips: Turning the distributor does not alter ignition timing but it does need to be in sync. The Powertrain Control Module (PCM) needs to see the Camshaft Position (CMP) sensor signal come at the expected time in relation to the Crankshaft Position (CKP) sensor.
Diagnostic Codes: None
Author: Michael Brown
Average Reported Mileage: 173255
I follow that and then recheck it with the snap on scanner and the scanner is saying it -13 off. I would of figur it be alot closer then that.