Lr4 misfire on all cylinders

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AndrewAgh21

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Hi everybody. I am a 21 year old that works with my dad at our shop.

I am new to this forum and was looking for some help.

Just did a timing chain job on a 2012 5.0L LR4.

Cranked the engine and it started up and just died down after about 30 seconds.
Started up fine then lost idle and just died basically.

Now the car will only start if you let it sit for 30 minutes or more. But when it does start the same thing happens. Runs for about 30 seconds then quickly dies. Codes are showing that the LR4 has misfires on all cylinders. We tested the injectors and they fire, Also checked the wires that connect to the injectors and they are good. There is fuel pressure so the mechanical fuel pumps are working fine. Also adjusted the fuel timing that is underneath the crankshaft timing gear to the left.

And the car still shows the same issue. Can anyone give me some new advise.
sorry if I mispronounce anything I am still considerably new to wrenching.

(My dad says that the fuel is getting restricted and that is why the car is shutting off)
 

Azoo

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When you started up the engine after the timing chain job was the idling smooth ? If yes then you wanna check all the wiring leading to the coils. if engine idling was not smooth then the timing is probably off.
 

AndrewAgh21

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Once the engine starts it runs smooth but after about 30 seconds it literally just jumps down 500 rpm then another 500 rpm and just dies out.

Will be checking all wires leading to coils and give an update.
 

Strizzo

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what happens if you give it throttle to try and keep it running? still just dies?
 

djkaosone

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Are there any codes you can share? If there are no codes, you may want to check timing again.
 

AndrewAgh21

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Hey guys, so we double checked the fuel pump camshaft timing and it's a full 180 degrees off.

Will re-adjust that and update on the issue.

to answer some of the questions -

I was not able to get the code, my dad scanned it on the auto-logic and said there were misfires on all cylinders. I would need him
to recheck and write down the codes.

Also if we give it throttle it runs perfectly. Only when we let off and let it idle does it die out.
 

djkaosone

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I really don't think you're 180 degrees off, otherwise you'll have bent valves. I have a thread called diy timing chain. I think you're off by a tooth or so. You might be able to reuse your tensioners by clicking them down and adjust your timing chain. On the back of the cam shafts, place a 1/4" bar to line up the intake and exhaust cam shafts, the crank should be at the 6 o'clock position to line it up properly. There should be timing marks on the chain and line them up with the markers too.
 

AndrewAgh21

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So adjusted the fuel pump timing and checked all wires leading to coils. Also checked all the injectors and they fire fine.

Code reads misfire with low fuel. added about 3 gallons of fuel into the vehicle and still the same problem.

At this point we are thinking it is a faulty ECU.

I have a video I am going to post so everyone can get a visual on what I mean.
 

AndrewAgh21

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Hi guys, That is the link for the video. I had to upload it to Youtube because it said the file was too big to upload here.

I do realize we do not have the fan pulley or the fan pulley belt on and that's because we were just testing to see if the engine would run smooth and idle on its own. (which it didn't)

In the video you can see the car starts after we adjusted the fuel pump camshaft. You can see in the video the car runs on it's own smooth for about 36 seconds then at the 36 second mark in the video the car just starts to idle very poorly. Then about 15 seconds later at the 51 second mark of the video my dad gives it throttle. You can hear the car rev up and run smoothly while his foot is on the gas. He keeps it on the gas and lets off for about a second at the 1:05 mark of the video and you can hear it drop RPM. He then puts his foot back on the throttle and the car runs smooth up until the 1:23 mark of the video where my dad lets his foot off the gas and the car just dies.

This happens every time we are able to start the car, as you can see. It runs smooth for about 30 seconds then slowly dies unless we keep our foot on the throttle.
In this case my dad kept his foot on the throttle to enable the check engine light to come on so we could check the codes.

Please let me know what you think. Thanks
 

Strizzo

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That does not sound like a healthy motor. It sounds like at least one cylinder is down on compression while cranking. Also poor idle while running ok at higher rpms points to this and/or the suspected cam timing being off.

I would do a compression test if possible to see if you have a valve hanging open or out of time enough that compression is affected. At this point it sounds like it’s gonna have to come back apart
 

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