P03000 random misfire
#12
#13
Since you just bought the truck and somebody obviously wanted to sell it. Look at the front of the block where the head meets on the port side and see if there is a black spot the size of a silver dollar.
I had a near identical situation but with p307 (rear side). It wasn't good news.
I had a near identical situation but with p307 (rear side). It wasn't good news.
#14
Changed plugs. The old ones looked good, but I figured, you never know.
Did the same thing. No service engine light, Ran nice and smooth and strong for about 2 miles and then the service engine light came back on and it started running rough. Got the 0300 back along with a 1300.
Good of news is that the 1412 is gone. I cleaned the driver side SAI valve while I was at it today.
So I’m guessing move on to 7mm wires, new coils and new 02 sensors.
02s are on the way, I’m gonna have to wait a bit for the coils and wires, I don’t think I can do that job myself.
Did the same thing. No service engine light, Ran nice and smooth and strong for about 2 miles and then the service engine light came back on and it started running rough. Got the 0300 back along with a 1300.
Good of news is that the 1412 is gone. I cleaned the driver side SAI valve while I was at it today.
So I’m guessing move on to 7mm wires, new coils and new 02 sensors.
02s are on the way, I’m gonna have to wait a bit for the coils and wires, I don’t think I can do that job myself.
Last edited by Daytoman; 01-26-2019 at 09:42 PM.
#15
So I gave up on Fixing this misfire issue myself ....but I hate when People start a thread on a problem and then never finish it. So I’m gonna update this thread.
In my 03 D2 it started with a misfire on 3.
I did the following to try to fix it:
2003 Disco
Cleaned MAF, TB and Idler Valve.
Ran OK for 5 mins then P0300 code came back. Misfire returned.
Changed plugs NGK (7092) BKR6EGP G-Power (did not change gap)
Recleaned MAF
Cleaned SAI valve.
Coils and wires changed.
Purge valve changed
O2 sensors changed
Still getting 1300, 0300,0301, 0303, 0305, 0307
Very Rough idle
crankshaft position sensor changed.
Ran sea foam through the intake.
Getting code 1300, 0300, 0301, 0303, 0305, 0307
Turned into all of bank 1 misfiring
very rough idle, barely runs.
I managed to take a single misfire and turn it into a complete bank one misfire.😂😂
Took it to a local Indy shop where they changed the plugs and made sure the wires were connected correctly and it did not improve at all so then they set it aside For four months and put project after project in front of me because they knew it was going to be something they have to dig into...and probably didn’t want to jack with it...
I paid them $200 for nothing, picked it up and took it to a new local Indy shop.
So the latest on it is that they disconnected the exhaust and it immediately idled and ran much better. I had purchased new Magnaflow cats for my 04 but left them with this shop just in case. So they are going to install those, hook the exhaust back up and keep going.
We’ll see what’s next.
In my 03 D2 it started with a misfire on 3.
I did the following to try to fix it:
2003 Disco
Cleaned MAF, TB and Idler Valve.
Ran OK for 5 mins then P0300 code came back. Misfire returned.
Changed plugs NGK (7092) BKR6EGP G-Power (did not change gap)
Recleaned MAF
Cleaned SAI valve.
Coils and wires changed.
Purge valve changed
O2 sensors changed
Still getting 1300, 0300,0301, 0303, 0305, 0307
Very Rough idle
crankshaft position sensor changed.
Ran sea foam through the intake.
Getting code 1300, 0300, 0301, 0303, 0305, 0307
Turned into all of bank 1 misfiring
very rough idle, barely runs.
I managed to take a single misfire and turn it into a complete bank one misfire.😂😂
Took it to a local Indy shop where they changed the plugs and made sure the wires were connected correctly and it did not improve at all so then they set it aside For four months and put project after project in front of me because they knew it was going to be something they have to dig into...and probably didn’t want to jack with it...
I paid them $200 for nothing, picked it up and took it to a new local Indy shop.
So the latest on it is that they disconnected the exhaust and it immediately idled and ran much better. I had purchased new Magnaflow cats for my 04 but left them with this shop just in case. So they are going to install those, hook the exhaust back up and keep going.
We’ll see what’s next.
Last edited by Daytoman; 09-17-2020 at 02:09 PM.
The following 2 users liked this post by Daytoman:
Richard Gallant (09-17-2020),
whowa004 (09-17-2020)
#16
Check your 02's again
disconnecting the exhaust sounds like the computer is no longer getting poor information from them and running a default mixture i.e. runs a lot better
Make sure the computer is reading the 02 voltages and they aren't stuck at .45 volts and they are actively oscillating between around .8v and .3 volts. <-- That would be for the upstream sensors(bank 1 sensor 1 and bank 2 sensor 1)
I didn't read the whole thread but if they are in there, pickup some kingsborne 8mm wires, i think they are like $30 and much more solid then the default 7mm wires you get. I run NGK plugs and they are fine. New coil packs are a must. and all 4 new BOSCH 02 sensors are a must. After all that might as well throw a MAF for good luck, I read you changed most of everything except the MAF so. If you stick with your coils and wires and 02 sensors, just make sure they are BOSCH 02 sensors, and the wires and coils are of good quality. Could be bad parts
disconnecting the exhaust sounds like the computer is no longer getting poor information from them and running a default mixture i.e. runs a lot better
Make sure the computer is reading the 02 voltages and they aren't stuck at .45 volts and they are actively oscillating between around .8v and .3 volts. <-- That would be for the upstream sensors(bank 1 sensor 1 and bank 2 sensor 1)
I didn't read the whole thread but if they are in there, pickup some kingsborne 8mm wires, i think they are like $30 and much more solid then the default 7mm wires you get. I run NGK plugs and they are fine. New coil packs are a must. and all 4 new BOSCH 02 sensors are a must. After all that might as well throw a MAF for good luck, I read you changed most of everything except the MAF so. If you stick with your coils and wires and 02 sensors, just make sure they are BOSCH 02 sensors, and the wires and coils are of good quality. Could be bad parts
#17
Check your 02's again
disconnecting the exhaust sounds like the computer is no longer getting poor information from them and running a default mixture i.e. runs a lot better
Make sure the computer is reading the 02 voltages and they aren't stuck at .45 volts and they are actively oscillating between around .8v and .3 volts. <-- That would be for the upstream sensors(bank 1 sensor 1 and bank 2 sensor 1)
I didn't read the whole thread but if they are in there, pickup some kingsborne 8mm wires, i think they are like $30 and much more solid then the default 7mm wires you get. I run NGK plugs and they are fine. New coil packs are a must. and all 4 new BOSCH 02 sensors are a must. After all that might as well throw a MAF for good luck, I read you changed most of everything except the MAF so. If you stick with your coils and wires and 02 sensors, just make sure they are BOSCH 02 sensors, and the wires and coils are of good quality. Could be bad parts
disconnecting the exhaust sounds like the computer is no longer getting poor information from them and running a default mixture i.e. runs a lot better
Make sure the computer is reading the 02 voltages and they aren't stuck at .45 volts and they are actively oscillating between around .8v and .3 volts. <-- That would be for the upstream sensors(bank 1 sensor 1 and bank 2 sensor 1)
I didn't read the whole thread but if they are in there, pickup some kingsborne 8mm wires, i think they are like $30 and much more solid then the default 7mm wires you get. I run NGK plugs and they are fine. New coil packs are a must. and all 4 new BOSCH 02 sensors are a must. After all that might as well throw a MAF for good luck, I read you changed most of everything except the MAF so. If you stick with your coils and wires and 02 sensors, just make sure they are BOSCH 02 sensors, and the wires and coils are of good quality. Could be bad parts
Yeah I’ll mention the voltages once the new cats are back on if it’s still misfiring. I did get Bosch O2 sensors.
#19
Just another update. The shop called today to let me know they had to clear some work that was ahead of me to get mine back up on the lift.
He said that the new cats have fixed my bank 1 misfire issue. But it stared a random misfire on bank 2 and is running rich. Compression check shows 150-160 on all cylinders. Tried swapping injectors but did not solve problem. Still working on it.
Any ideas, please throw them out.
He said that the new cats have fixed my bank 1 misfire issue. But it stared a random misfire on bank 2 and is running rich. Compression check shows 150-160 on all cylinders. Tried swapping injectors but did not solve problem. Still working on it.
Any ideas, please throw them out.