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p0301 code on a newly rebuilt motor in 01 xj

W

wheelinwv

NAXJA Forum User
Location
st.albans wv
whats up guys....just finished rebuilding my motor in my 01 cherokee an cannot get this code to go off....heres what ive done... i replaced everything in the block besides the crank,rods an pistons...its a 94 block an i put the head off the 01 on it due to a wrist pin locking up an destorying the #1 cyl....i didnt have any head work done... it looked as if it didnt hurt the valves..just a small scratch on the intake valve....bent the hell out of the pushrods on cyl 1.... i replaced the pushrods.... now that its together its throwing a cyl 1 misfire an going into limp mode... ive swapped the injectors around an spark plugs ..no changes.. thought it could be the coil but i figure it would throw a multiple misfire...my question is could the camshaft sensor being out of sync cause just the #1 cyl to misfire....or should i look somewhere else....what should i look for
 
also sounds like i didnt get one of the lifters pumped up completly...makes a small ticking noise...could that be my issue? any advice would be appreicated
 
P0301 is a pain to figure out. Get your valves pressure checked (can rent the tool from O'Riely) and make sure the numbers are all within 50 (correct me if im wrong). If that doesnt work start pulling off connectors to your sensors and cleaning them. Have the battery load tested as well. Keep us posted if those dont work we'll go from there.
 
Another thing you can do real quick is clean the distibutor cap / rotor. I used scotch bright pad and a little bit of WD40 (im talking very little) and wiped it out with a clean rag. Make sure the spark plug wires are seated right on the number 1. Pull the number 1 spark plug and see if its fowled up. It probably wont be but you never know. After that you can get a inline spark tester from any auto shop (NAPA O'Riely etc) and see if you have spark. Or you can stick a flat head with a rubber grip in the spark plug cable while its off the plug and have someone crank the engine. Not the best way to do it cuz it shocked the holy hell out of me but it does the trick.
 
What's the history behind the motor? What caused the damage to the valve? You said your pushrods got destroyed. Why?
 
well the old motor had a wrist pin lock up on #1 cyl the piston wedged itself between the bottom of the cylinder an the crank....bent the pushrods in between all of that...
 
im gonna do a compression check on it sometime this weekend an il post results for that...
i also noticed today i took it for a drive an when it gets up to normal op temp the oil pressure will shot down an go to zero if u have to stop quickly ....checked the oil an its clean ....any ideas on the i bought the meiling high volume pump
 
do you have a generic scan tool? are you able to pull up pids with it? if so can you tell me the STFT? Just to start. Did you do any measuring of any of the parts or did you just order new parts and slap them in? If you can't get access to STFT you can do a compression test, as well as a leak down to check.
 
The scanner im using is a blue point mirco scanner.. an my buddy who works at a dodge dealership here in town measured everything an was with me on the rebuild
 
Cam sensor timing could be the problem, could also be the coil bar. It is possible for one coil to fail in the bar.
You need a DRBIII to check the camshaft sensor timing
 
i was wondering myself if the camshaft sensor timing could be the problem... ima try a coil pack tommorrow also do a leak down test an compression check just to rule out the possible issues
 
not familiar with the blue point scanner you have but will it give you access to pids? Short term fuel trim depending on what it is will help give a good diagnostic starting point to your misfire. Post up i you can find out the numbers.
 
i looked on it only thing it shows me is live data an access to codes..... i also barrowed my buddys coil pack off his tj an i still have the code mine worked fine on his as well....if i get a chance tommorrow ima run a compression check an fill the cylinder with air an check out the valves
 
depending on what the numbers you give will help you and give you a starting point...instead of wasting your time on diagnosing something that isnt wrong..post up the number weather its +/- and it will, should help give a good starting point if its a fuel, spark or mechanical problem
 
Decided to change the spark plugs over to ngk coppers an noticed that the old champion plug i had on #1 was completely black/brown... all the others look like have been firing good
 
2013-01-27_13-14-16_49_zps40de07cc.jpg.html
 
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