Engine won't run after tummy tuck install

[glenntroy]

Hi, I recently purchased a 2005 4.0, 6 speed unlimited wrangler. The car has run perfectly until this past weekend when I did a tummy tuck. Since the TT, the car turns over a lot longer before starting, and then it idles rough and dies. It feels like the engine is not running on all cylinders. I pulled the code from the dash (on off on 3 times) and it gave me code P0522 which is the oil pressure sender.



A few questions for the group. I’m hoping someone could answer:

1. from what I understand the oil pressure sender is used for the gauge in the dash and therefore it should have no effect on how the engine runs, is that correct?
2. when I was doing the TT (i know stupid of me), I hadn’t unhooked the battery and I put a socket wrench on the battery terminals and it sparked for a second, is there a chance this affected the ECU and therefore the engine running properly?
3. for anyone who has done a TT? Are there any wires, sensors or hoses that are in the way and potentially got smashed when pushing up the tranny?

My plan tomorrow is to lower the skid plate and transmission to see if anything got smashed or any wires that were damaged, but I’m hoping someone has had experienced with this and has some ideas. Thank you in advance.

 

[cb4017]

Welp, I'm new to the TJ world but have to ask. What is a Tummy Tuck??

 

[GregBelleville]

Hi, I recently purchased a 2005 4.0, 6 speed unlimited wrangler. The car has run perfectly until this past weekend when I did a tummy tuck. Since the TT, the car turns over a lot longer before starting, and then it idles rough and dies. It feels like the engine is not running on all cylinders. I pulled the code from the dash (on off on 3 times) and it gave me code P0522 which is the oil pressure sender.



A few questions for the group. I’m hoping someone could answer:

1. from what I understand the oil pressure sender is used for the gauge in the dash and therefore it should have no effect on how the engine runs, is that correct?
2. when I was doing the TT (i know stupid of me), I hadn’t unhooked the battery and I put a socket wrench on the battery terminals and it sparked for a second, is there a chance this affected the ECU and therefore the engine running properly?
3. for anyone who has done a TT? Are there any wires, sensors or hoses that are in the way and potentially got smashed when pushing up the tranny?

My plan tomorrow is to lower the skid plate and transmission to see if anything got smashed or any wires that were damaged, but I’m hoping someone has had experienced with this and has some ideas. Thank you in advance.

Is it possible you damaged the crankshaft position sensor? It's located on the top of the bell housing.

 

[hosejockey61]

Check for pinched wires as well. @jjvw chased a cut out issue for a long time. I would wiggle wires around while it's running to see if there is any change.

 

[macleanflood]

When I did my tummy tuck I also installed MMLs...I pulled the evap line off my charcoal canister causing a high idle.

My guess is you pinched a fuel line...I'd verify your pressure...or your fuel pump decided today was the day.

Did your Jeep sit for a while during the tuck?

-Mac

 

[jjvw]

Check for pinched wires as well. @jjvw chased a cut out issue for a long time. I would wiggle wires around while it's running to see if there is any change.

Best I can figure is that mine was a loose O2 sensor after replacing all of them in the months prior. The problem disappeared after I unplugged and reseated every sensor on the engine and transmission.

Since the Jeep is new to the OP, my best guess is that the raised engine and transmission moved something that was already loose.

 

[glenntroy]

When I did my tummy tuck I also installed MMLs...I pulled the evap line off my charcoal canister causing a high idle.

My guess is you pinched a fuel line...I'd verify your pressure...or your fuel pump decided today was the day.

Did your Jeep sit for a while during the tuck?

-Mac

View attachment 593602

No, the work was done in one day. I’ll check fuel lines and see if something got tweaked. Thanks

 

[jjvw]

Welp, I'm new to the TJ world but have to ask. What is a Tummy Tuck??

Tummy tuck is when we raise the Jeep's belly up.

 

[glenntroy]

Is it possible you damaged the crankshaft position sensor? It's located on the top of the bell housing.

This in one of the items on my checklist when I drop the pan. Would a bad CPS cause the engine to run rough, in my experience it only make it harder to start but then the engine runs fine afterwards?

 

[L J]

Welp, I'm new to the TJ world but have to ask. What is a Tummy Tuck??

 

[glenntroy]

Welp, I'm new to the TJ world but have to ask. What is a Tummy Tuck??

Tummy tuck is when you lift the tranny and transfer case and replace the stock (shovel) skid plate with a high clearance skid plate. The result is better clearance and it looks better

 

[JKP]

Spark is based off the crank sensor. Can even cause a no start. 05 and 06 will eventually start with a completely bad one IIRC, but with a long crank.

My guess is chafed wires for both issues.

If you are getting codes from the PCM, it's at least up and running.

 

[glenntroy]

Does anyone think the mistake with the socket wrench on the battery terminals caused any issues with the ECU? I wouldn’t think so but curious what others think.

 

[glenntroy]

Spark is based off the crank sensor. Can even cause a no start. 05 and 06 will eventually start with a completely bad one IIRC, but with a long crank.

My guess is chafed wires for both issues.

If you are getting codes from the PCM, it's at least up and running.

This is very helpful information, thanks

 

[GregBelleville]

How do your terminals look after you arced your wrench to it?

 

[jjvw]

Does anyone think the mistake with the socket wrench on the battery terminals caused any issues with the ECU? I wouldn’t think so but curious what others think.

A short between pos/neg directly at the battery should have no impact on the PCM. The current only passed though the wrench.

 

[glenntroy]

How do your terminals look after you arced your wrench to it?

It was just a second so they look normal.

 

[glenntroy]

As an update, I lowered the skid plate and didn’t see any issues, so I replaced the crank position sensor and tried to start the car again and apparently the car runs better with the crank position sensor unplugged then when it’s plugged in. I’m also getting codes P2308 and P0016 now. My question for you all is should I replace the OPDA and the camshaft sensor too? I hate throwing money at this but the engine has 300k miles and I have no idea how old the OPDA is.

I’ve read that if either the camshaft position sensor or the crankshaft position sensor is bad then the engine will not run well which I think is my issue. Has anyone had a similar experience to this? I really appreciate your help, this is all new to me.

 

[JKP]

Normally the crank sensor triggers the spark and the cam sensor is used to fire the injectors. 05 and 05 have a different PCM and cam/crank sensor setup than previous years and can use 1 of them to figure it all out if needed.

I'd start with replacing the crank sensor.

If the OPDA has LDI on it, it is the original design, which has issues.

You at least need to pull it and see if the OPDA gear is worn.

Keep the original cam sensor if you replace the OPDA, as they tend to be better than the aftermarket ones. Assuming it's not bad.

 

[jjvw]

...I’m also getting codes P2308 and P0016 now. ...

And what are those codes?