2010 4.0 convertible engine trouble

[Thunder3673]

Hello all, I’m new to the forum and have cross posted this to get as much information as possible. Thank you in advance!! I am reaching the end of my road with this car and not sure what to do next. The car was running decent and I had to pull engine to replace the timing cassettes. After getting it back together I drove it to work a few days, about 100 mile round trip, with no issues. Then I had to run through town one day. It started jerking, just running crappy. It actually cut off at one point and would not start back. After messing a few minutes I finally got it started and made it home. I drove it a few more times to work and it seemed ok at Hwy speeds, maybe a slight jerk here and there. I have been trying to find the source of the problem the last week or so. It keeps throwing codes for po320 and po607. I have changed the crank sensor, cam sensor, plugs, throttle body with both sensors, stripped the wire harness open from engine to pcm and inspected, back probed wires feeding the crank and cam sensor to make sure one wasn't broken or shorted. I have changed the alternator. Luckily I also have an 07 with the 4.0 so I had parts available to swap and not have to go out and purchase parts to try. So far there's no real difference. I notice it terribly when I pull out on the hwy and floor it. Most times it will get up to 2500 rpms or so and cut out. If you continue pushing it it throws codes po2105 and 2107 and U0300. I was sitting in the car just flooring it earlier and saw the battery light flash on for just a second but according to the scan tool and a voltage meter the voltage seems to be consistent. Not sure why the light gets triggered?? I have double checked that I didn't forget a ground cable somewhere but haven't found anything loose. Does anyone have any ideas?

 

[whitmanink]

well u either have a bad spark plug or plugs,,
bad coil block ,

or ecu is corrupt or damaged ..

if i were you id get a compression test to make sure all is ok and it didnt jump timing ..
change the plugs and coil block,

then if it still isnt right id look into the ecu

or the alt is bad too and you dont know it (altho rare)

 

[Thunder3673]

I just changed plugs and coil pack. Al this seemed to start when I pulled engine and put new timing cassettes in. My next move is probably a pcm? I drove it about 50 miles this morning to work and the check engine light did come on but it ran perfect. I didn’t ever floor it but normal drive it was fine. Hoping something about those factory style cable ends were giving issues. I’m going to get it on the lift this weekend and make sure there’s nothing I accessed from the bottom that got left off or loose? I don’t remember any type of grounded straps down there but I don’t remember. I have checked one on shock tower, a main ground wire on the back of the left head and a strap that hooks to the body on the firewall and runs to a small bolt on the intake. Honestly the starter wires are all I can remember underneath? I will also check the new code and see what it has. I also noticed this morning the stereo would not come on. I have had some issues with the SJB in passenger floorboard. I actually removed and checked/cleaned everything on it last week but didn’t seem to make any difference. I had a bunch of trouble with it several years ago causing egr codes. Worst thing with this car is wiring harness and SJB are no longer available and from what I understand the convertible was a one year only for any of these parts. Told my wife we would sale it but I don’t want to give someone else issues by doing that!

 

[Thunder3673]

I had run a compression check several weeks back and it was good. I also swapped the alternator with our 07 and it was the same.

 

[whitmanink]

I'm Wondering if the sjb is bad or ur ecu at this point ..

What were the codes that come up when u just drove it?

I did get back plugs once from AutoZone in my wrx .. thought I had major engine trouble and here it was two fluke plugs?

Im kinda in your boat with my 3v ..
Just trying to get it going

 

[Thunder3673]

I know the SJB caused a lot of headaches with engine codes as well as the stereo system. I will see what codes set this time when I get off this afternoon and let you know. I got the standard motorcraft copper plugs but actually only replaced 5 because 1 of the from O’Reilly had a broken electrode and I just got it swapped yesterday. May be a chance it or one of the other new ones could be bad but I don’t have a consistent skip and pulling plug wires from each cylinder seem to affect it equally. I will post when I get the fresh codes this afternoon

 

[whitmanink]

Maybe even try pulling the sjb and open her up.. take some crc electric cleaner and spray away and maybe get some unseen corrosion off ...

Also just pull the engine grounds and wire brush them and make sure they are metal on metal

 

[whitmanink]

maybe clean the maf ,,
altho im thinking its a bad or corroded board on the sjb or ecu ..

but it happend after the timing ,,
you said it drove fine for about 100 miles then acted up,,

just Dubble check the sjb or ecu dnt have signs of corrosion or burnt spots ,, or spots that seem odd colored ,..

can u do a live data and check your o2 sensors among other sensors ?>