Engine shut off / P0129, 290, 325, 330, 340

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DakMack

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So running my 05 KJ the other day (200k on body/100k on engine) up a serious mountain in my area (3,200 ft) and quite step slope about 3or4 miles, my cruise set on 70mph, a/c running wide open bc it was 90some degrees and humid as all get out, stereo pounding and signing along and she just shuts off..

I have had 2 codes on (P0420 and P0430) since swapping out the OEM catalytic converters with flowmaster's before going on a 2,000 mile trip.

Back to my experience, I checked the codes after she shuts off and I'm getting P0129 (barometric pressure low), PO290 (cylinder 10 contribution), P0325 (knock sensor 1), P0330 (knock sensor 2), P0340 (CPS signal reference to wiring/timing).

So I sit there a moment.. Take a look under the hood and all wiring to sensors look fine so I jump back in to turn it over and it cranks for 5or6 seconds, starts up and the rpms are all over trying to get to idle. At this point, I'm 2 minutes from my destination but 35 miles from my garage.

I proceed to my destination and I can't get any type of higher rpm out of my 3.7L. She shifts to 2nd and acts like I'm at the limiter at 2500rpm and will not shift. Also, when letting off the throttle, I'm almost stalling so instantly I'm thinking I have an unsteady fuel issue, possible faulty sensor or dreading a problem with the timing kit/head gasket disaster I completed 5k ago.

Make it to my destination and disconnect the battery to rescan. I'm getting the same codes mentioned plus P0010 (timing sync between CPS AND CKP).

I start by unplugging sensors and try googling codes with 1 bar of service (fun!!). I find interest in the barometric pressure code that bases off altitude and temperature off other sensors and also, the CPS as I've already had 1 faulty CPS (duralast) since timing kit install.

I decide that she's running in failsafe mode and press on home. As long as I stayed in low rpms, up and down hills, it ran okay but a problem was apparent.

Make it to the garage safely and start tearing apart to diagnose. I decided to replace the MAP sensor as the barometric pressure refers to it and not a BPS/BAP sensor on this style engine. I quickly see that I should remove the alternator and ac compressor to gain access to the MAP sensor bolts. Forgetting to disconnect the battery (unlike me but trying to quickly diagnose), the hot wire to the alternator flips back touching the fuel rail, throwing sparks and then ablaze. The spark punctured 2 pin holes in the rail and it's blowing flames 3 feet. I quickly pull the wire off and smother the flame then frantically try unhooking the battery and battery mount to remove from engine bay.

Remove the battery and patch the fuel rail to keep diagnosing. I buy a MAP sensor (duralast) and throw it in, still getting codes for barometric pressure low/out of range and a code referring to CPS wiring return signal.

Do some research and decide that I'll remove the CPS next. When I disconnect the wiring, remove the 10mm bolt and pull out, the end of the sensor (being magnetized to my knowledge) is covered with a dark gray, almost black looking thick liquid (possibly anti seize?). I wipe the sensor clean and throw back in. She still takes 5 seconds to crank then starts and the rpms are all over once again but not as bad.

I jump on the bike and go get a new CPS (duralast) get back home and throw it in. Starts right up without delay, runs perfectly with no codes.

I thought is this real life? I double check everything UTH being plugged up and tight and go for a ride. I think it runs better than before and the shift points seem slightly lower (I prefer living in the mountains).

The end result was a new MAP sensor and a new CPS and I now have no codes.. Not even the 420 and 430 on my converters not being full obd2 compliant so idk but I'll take it.. Idk if the MAP sensor was needing or not but it's staying on there and I bought a new TPS that can sit in the glovebox till possibly needed as well.

I still need to swap the fuel rail off my old engine and do some more research on to what was collected on the tip of the CPS. And I'm buying new converters to avoid future issues. But all seems well with the old girl but I'll thread lightly...

Quite a story and quite an outcome. Hopefully this entire ordeal can help someone else out and maybe shed some light onto diagnosis if anyone out there is dealing with similar issues..

Give me a yell if you have any questions to anything..

Dakmack out...
 

tommudd

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I'd be buying some MOPAR replacement parts to have so when the duraneverlasts die soon, you will be prepared
 

DakMack

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I'd be buying some MOPAR replacement parts to have so when the duraneverlasts die soon, you will be prepared

I've been told duralast are quality replacement parts with OEM numbers but I looked into it and spoke with a Autozone rep.

I was eventually told that their batteries are made in China and I say, if they are, they all are.

I plan to get mopar brand sensors to replace. Any take on Rock Auto or Parts Geek etc. being quality mopar parts?
 

Billwill

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I am surprised the "Fusable Link" did not blow when you created all those sparks! This is the thick wire that goes from battery positive to the alternator and has a fuse built into the wire to blow when you get a short like this.:confused:

You would know if it had blown as your Battery Charge light would come ON when running...must have been a very short duration short!

I saw a post somewhere where a KJ Owner had a CPS problem...on removing the CPS he found small metal particles sticking to the magnetised end...not a good sign!o_O
 

DakMack

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I am surprised the "Fusable Link" did not blow when you created all those sparks! This is the thick wire that goes from battery positive to the alternator and has a fuse built into the wire to blow when you get a short like this.:confused:

You would know if it had blown as your Battery Charge light would come ON when running...must have been a very short duration short!

I saw a post somewhere where a KJ Owner had a CPS problem...on removing the CPS he found small metal particles sticking to the magnetised end...not a good sign!o_O

As far as the fusable link goes, I don't believe I've ever took notice to it. Although, I'm quite glad I'm not having the issue you mentioned atm at least. The sparks were a short duration but the alternator was unhooked. Signal unplugged and the hot to alternator is what touched the fuel rail.

On the CPS sensor issue, I really do not know what to assume to be covering the CPS metal tip (Reader/Indicator to cam gear). It was just the magnetized end. The rest of the CPS was clean and coated with motor oil as we would expect.

I'm going to continue to research what may have been coated on that sensor. Is anti seize magnetic haha :rolleyes: Thanks, @Billwill
 

daves06lrenegade

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The fuseable link is between the battery and the alternator and is there to protect the battery "if" the alternator or the wiring going to the alternator gets shorted to ground,,, Like a "slow blow" fuse the link didn't have a short to ground for a very long period and the link survived...
I have had days like yours but they don't last :)
Dave
 

DakMack

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The fuseable link is between the battery and the alternator and is there to protect the battery "if" the alternator or the wiring going to the alternator gets shorted to ground,,, Like a "slow blow" fuse the link didn't have a short to ground for a very long period and the link survived...
I have had days like yours but they don't last :)
Dave

Well that makes for pretty good luck to me.. I did a little looking around and was able to see in there a little bit.. The fuse on my 05 KJ is wrapped up in a factory electrical tape mixed with shrink wrapping.. I was lucky indeed and better days always come around.. Thanks, @daves06lrenegade
 

Billwill

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Yeah if that "fusable link" blows you are supposed to replace the whole wire as a unit.

Different year/models have different color wire with different Amp rating!

Many years ago, fresh out of Tech Collage and working for IBM in the field, I was stranded with a Toyota pickup....measured that the fusable link was blown for some reason or other!:eek:
I was in the middle of nowhere so was forced to bypass the fused section to get me home. Fitted a new fusable link and never found out why it blew in the first place!:confused:
 

DakMack

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Seems to be good information to know and I'll take all the knowledge can get.

As far as to your experience, seems odd enough out of a good old *** truck but every dog has his day, for better worse.

At least you knew your way around the engine bay, being high and dry that far out can be a serious drag, I know it.
 

Blue Gen

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So running my 05 KJ the other day (200k on body/100k on engine) up a serious mountain in my area (3,200 ft) and quite step slope about 3or4 miles, my cruise set on 70mph, a/c running wide open bc it was 90some degrees and humid as all get out, stereo pounding and signing along and she just shuts off..

I have had 2 codes on (P0420 and P0430) since swapping out the OEM catalytic converters with flowmaster's before going on a 2,000 mile trip.

Back to my experience, I checked the codes after she shuts off and I'm getting P0129 (barometric pressure low), PO290 (cylinder 10 contribution), P0325 (knock sensor 1), P0330 (knock sensor 2), P0340 (CPS signal reference to wiring/timing).

So I sit there a moment.. Take a look under the hood and all wiring to sensors look fine so I jump back in to turn it over and it cranks for 5or6 seconds, starts up and the rpms are all over trying to get to idle. At this point, I'm 2 minutes from my destination but 35 miles from my garage.

I proceed to my destination and I can't get any type of higher rpm out of my 3.7L. She shifts to 2nd and acts like I'm at the limiter at 2500rpm and will not shift. Also, when letting off the throttle, I'm almost stalling so instantly I'm thinking I have an unsteady fuel issue, possible faulty sensor or dreading a problem with the timing kit/head gasket disaster I completed 5k ago.

Make it to my destination and disconnect the battery to rescan. I'm getting the same codes mentioned plus P0010 (timing sync between CPS AND CKP).

I start by unplugging sensors and try googling codes with 1 bar of service (fun!!). I find interest in the barometric pressure code that bases off altitude and temperature off other sensors and also, the CPS as I've already had 1 faulty CPS (duralast) since timing kit install.

I decide that she's running in failsafe mode and press on home. As long as I stayed in low rpms, up and down hills, it ran okay but a problem was apparent.

Make it to the garage safely and start tearing apart to diagnose. I decided to replace the MAP sensor as the barometric pressure refers to it and not a BPS/BAP sensor on this style engine. I quickly see that I should remove the alternator and ac compressor to gain access to the MAP sensor bolts. Forgetting to disconnect the battery (unlike me but trying to quickly diagnose), the hot wire to the alternator flips back touching the fuel rail, throwing sparks and then ablaze. The spark punctured 2 pin holes in the rail and it's blowing flames 3 feet. I quickly pull the wire off and smother the flame then frantically try unhooking the battery and battery mount to remove from engine bay.

Remove the battery and patch the fuel rail to keep diagnosing. I buy a MAP sensor (duralast) and throw it in, still getting codes for barometric pressure low/out of range and a code referring to CPS wiring return signal.

Do some research and decide that I'll remove the CPS next. When I disconnect the wiring, remove the 10mm bolt and pull out, the end of the sensor (being magnetized to my knowledge) is covered with a dark gray, almost black looking thick liquid (possibly anti seize?). I wipe the sensor clean and throw back in. She still takes 5 seconds to crank then starts and the rpms are all over once again but not as bad.

I jump on the bike and go get a new CPS (duralast) get back home and throw it in. Starts right up without delay, runs perfectly with no codes.

I thought is this real life? I double check everything UTH being plugged up and tight and go for a ride. I think it runs better than before and the shift points seem slightly lower (I prefer living in the mountains).

The end result was a new MAP sensor and a new CPS and I now have no codes.. Not even the 420 and 430 on my converters not being full obd2 compliant so idk but I'll take it.. Idk if the MAP sensor was needing or not but it's staying on there and I bought a new TPS that can sit in the glovebox till possibly needed as well.

I still need to swap the fuel rail off my old engine and do some more research on to what was collected on the tip of the CPS. And I'm buying new converters to avoid future issues. But all seems well with the old girl but I'll thread lightly...

Quite a story and quite an outcome. Hopefully this entire ordeal can help someone else out and maybe shed some light onto diagnosis if anyone out there is dealing with similar issues..

Give me a yell if you have any questions to anything..

Dakmack out...
That is quite a story, I'm on this morning looking for info on something else and noticed your comments. Notwithstanding your problems and accidental damages, reading about the codes, sensors and such issues... doesn't everyone prefer Non digital autos running off mechanical distributor ?
 
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