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4.0 swap now wont run

2K views 18 replies 4 participants last post by  jclaudii 
#1 ·
Hey guys I just completed swaping out my old 4.0 with a 01 4.0 from a totalled jeep. I changed all gaskets including head gasket and now everything is back together. I went to start her up and all it does is sputter and pop out of the intake any ideas? Could I have messed up my crank sensor? Im getting codes p0351 and p0352 I changed coil and plugs no difference please any help?
 
#2 ·
Did you set the timing properly:

Line up the mark on the harmonic balancer with the mark on the timing cover.
Remove the Camshaft Position Sensor:
This:


Located Here:


You will see a hole in the casing of the distributor/cam position sensor (whichever you call it) and a hole on the inside ring. Line the two up and tape in a drill bit or nail to hold it perfectly in place. Slip the sensor back into the hole and clamp it back down before removing the drill bit.

It should run pretty well from here. You will need to take it to a dealer and have them set it with their DRBIII tool to make sure it is perfect.

You may have already done this but I overlooked it and was having a horrible rough running engine.
 
#4 ·
Hmmm... If you haven't taken it out, it may be fine. Removing it will mean you should eventually take it to a dealer to be properly timed. At the same time, who knows if it's been bumped or removed before you got it.

Since you are getting codes involving the ignition coil, I'd look there first before removing the cam position sensor. I see that you replaced the ignition coil. Did you replace it with your old one? Is it bad? Is it the correct one? Is it seated properly? Are there any issues with the wiring? Did you put in new, proper, spark plugs? Just some questions to maybe lead to a solution.

If you can eliminate any issues with the above questions, I'd maybe check the crankshaft position sensor.

For some reason, I feel tweaking with the Camshaft Position Sensor might be just what you need. I did a little searching and a few other occurrences kind of suggest that as well. It just seems to stand out to me for some reason...
 
#7 ·
If you look at my threads, I did a write up on changing the camshaft among other things. It is in there towards the end.

It is really pretty simple though. If you crawl under the front and hook a breaker bar to the harmonic balancer pulley bolt (the big one on the bottom) and rotate it clockwise until the line on the pulley lines up with the mark on the timing chain cover (I think the mark is right on the cover towards the top passenger side of the pulley), you will have it set at TDC on cylinder 1. Then you line up the two holes on the cam position sensor (with the sensor removed), secure it in place (I taped in a drill bit after I inserted it through both holes), then slip the sensor back down in the hole in the block. You will probably have to gently rotate the sensor back and forth until it slips ALL the way down. Secure the sensor and then remove the drill bit/tape.
 
#8 ·
ok so i did what you said and i got the jeep to run for about 30 seconds but it would not idle, the codes all went away but now it wont run again, im sure all wires are hooked up correctly and that the timing has to be close, when it was running the motor sounded a little tight, do you think that i could have over torqued the rocker arms to much causeing it not to run?
 
#9 ·
So did it run better or worse in your opinion? Sounds like if the codes didn't pop up and it wasn't backfiring, you are getting closer.

You ask if you could have torqued the rocker arms too tight... I'm curious as to how you came to ask that question. Did you use a torque wrench or do you feel you did tighten them too much?

It ran for 30 seconds... did it die on it's own?

Here's something you can attempt. Loosen the hold down for the camshaft position sensor and VERY slightly turn it one direction... like 1 degree slightly. Try to start it. No luck, turn it back the other direction very slightly. You may be off a bit still. When mine was off, it had a hard time idling but it could handle a small amount of throttle. Once I hit about 2k rpm, it would die and have trouble starting back up. Mine was also running very rich.
 
#10 ·
I am curious about the rockers because I was reading the book on the torque wrench and I may have been using the wrong line on the wrench so it would be about 5 pounds over tightened when I get home from work in going to do what you said turning the cam sensor if I.can't get it to run tommrow I am going to re torque the valves
 
#11 ·
Sounds good...

I assume the engine you put in was running before you put it in, right?
 
#12 ·
I did not hear it run but I did see the totalled jeep it came from. Ok so I got it running it will not idle around 2k rpms it surges but not all the time the engine turns over easy then all of a sudden it will turn over hard and then easy again. I can get it to run now another thing cats are red hot.didn't have an.issuse with them.before thinking.its just the way its running. So far no.codes any ideas
 
#13 ·
Ok mine did exactly that - the cat's turned red on mine meaning it was not timed properly. If I were in your shoes, I'd either fiddle with the cam position sensor by slightly turning one way or the other OR I would re-do what you did yesterday. It sounds like you got it close but not quite close enough. Honestly, the latter is probably the best choice. Remember, once you slip the sensor back in the hole in the block, tighten it down before removing the nail/drill bit. When tightening that bolt down, do not move the sensor at all. That WILL throw it out of time.

I'll try to watch this thread as best as I can this evening but I have a 4 hour gig tonight so in about an hour, I won't be able to check in on the issues until at least 10 - 11 tonight.

Good luck, and don't run it too much if it's acting funny or turning the cat's red. I imagine it's a little hard on them!
 
#15 · (Edited)
have you replaced the crank sensor or at least put your old one on. When the crank sensor goes, it causes weird codes and stalling and no run issues. Most of the time the crank sensor throws codes that are in no way related to the crank sensor, like misfire, crank and cam sensors, etc. For a $30 dollar part at a parts store or your old one it's worth swapping...a little bit in the pain to swap, but at least it is a bit of reassurance.

Also, did you gap your plugs? and what plug are you running?
 
#17 ·
the map sensor usually throws a code, but since you have so few run cycles on your engine, it may not hurt to slap on your old one and see what happens. I swapped all my parts to my new engine and it ran crappy and backfired when I tried to give it gas, it would eventually throw the map sensor code...I guess it got wet or something so I swapped it with the donor car's and all was fine!
 
#18 ·
If the plug on your 01 coil is opposite of your 99, you NEED to use a 99 coil again. It'll fire at 180 deg off.
 
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