Jump to content
Posted

Well on the way home last night I decided to get on the skinny pedal some on the onramp.  Truck pulled great egt's nice no issues, let out of it somewhat fast and barked the turbo and BAM lost my RPM gauge, CEL pops on.....ugh,  Truck drives fine all the way home so I thought eh who knows.

 

Last night I decided I also wanted to load a new tune onto my ADR to try and clean up some of the low end smoke if I am on it.  I have extra fuel thanks to the DFI injectors so I don't really need the aggressive tuning down low.  So I load the factory tune back onto the ADR.   

 

Jump in the truck this morning and my Quad says my Boost is at 11 PSI just sitting there, :doh: and my oil pressure gauge is reading 10-12psi no change with RPM......

 

RPM gauge on the dash comes and goes, but the quad screen shows RPM fine so I know that the ECM is seeing RPM fine.  WTS is working good and I have .01 ac noise so I am good there.

 

Codes are

p1756

p743

p336

p336 or 337 cant remember

p1688

and p0235

 

So seeing as all of this happened right as soon as I let off I am all but positive that the issue is a bad ground or something, maybe I melted a wire.  

 

Anyways I will dig deeper into it later today, but I figured I would let you guys know the fun I had.  

 

  • Replies 22
  • Views 2.9k
  • Created
  • Last Reply

Top Posters In This Topic

Most Popular Posts

  • So to update people as soon as I unplugged my new Oil pressure sensor I got 5v on my map.    I am not going to tackle the crank sensor as the t

  • Very very valid thought.     I would LOVE to have a spare ecm to pin out.

  • I talked to him awhile ago and he didn't seem to remmeber much.   We might throw some money at him and see if he will sell it all to us.

Featured Replies

  • Owner

the P1688 is the scary one...

Double check your P0235 there isn't such code for our trucks. I would assume its P0236 which would point to a Boost Fooler issues in the Quadzilla. Boost volts are too high too long.

Might have to do a dry run without the quadzilla and see if the code can be cleared and stay away.

9 minutes ago, Me78569 said:

Jump in the truck this morning and my Quad says my Boost is at 11 PSI just sitting there, :doh: and my oil pressure gauge is reading 10-12psi no change with RPM......

Might have to do a dry run without the quadzilla and see if the code can be cleared and stay away.

  • Author

Yea I was a little taken back by the 1688 code haha.  

 

I am gonna reload the quad again, drive home, borrow a scanner and see what comes up.   ( I reloaded the quad last night using a virtual machine with a virtual USB passthrough driver so who knows what effect that had on the flasher program hahahahaha.  I am guess, well hoping that the reload will fix the strange readings.

 

I accidentally unplugged the ADR box with the truck on so some of those codes are due to that.

Edited by Me78569

  • Owner
4 minutes ago, Me78569 said:

borrow a scanner and see what comes up. 

I'm shocked that you don't own a scan tool.

Edited by Mopar1973Man

  • Author

I do....well I did.... it is hacked apart and the USB --> Bluetooth ripped out and bypassed directly to Serial so I can read Canbus data for my turbo controller

 

So I do...but it is too much work to get it working with my phone again.  I need to buy another one, but I have been lazy.

Yep p0237 with the quad plugged in and no code with the quad unplugged. 

 

Only codes present were 336 and 237 so I am guessing that the vp44 is til good ( at least I hope)

 

I now also have a non-starting truck sitting at work.....ugh

 

HOWEVER my oil pressure is now reading 99PSI so I am really thinking I have a ground issue or something similar, I am gonna dive into the wiring diagrams and see if I can't race some wires over lunch.  I just can't imagine 3 sensors going bad at once.  

 

 

  • Author

Yep,

 

strange that this all happened at the same time.   I need to go out there and test the Ground s165 

I really wish I knew which sensor did what between the cam and crank.   strangely the crank sensor is on it's own ground.....  Also very strange that the truck was running fine but the tach was dead.  The tach would come and go, but I suppose that makes sense if the pcm / ecm was telling the cluster hey the cpk is bad.

  • Owner

Remember VP44 has a tone wheel too. So the crank sensor in the block might of died but the VP44 can still operate off its own tone wheel. This is why the BlueChip hot wire trick for testing the VP44 there is no ECM or sensor data its a stand alone VP44.

If need be you might have to go that route to verify too is Bluechip hot wire test and see if the engine starts.

  • Author

I just ran out and tested the grounds on map and coolant and they are good to go so I am ruling out busted ground.

 

Mike,

 

Does the ground on the passenger battery that grounds the pcm and ecm also ground the sensors that are connected to the ECM?  

 

IE if I unplug the passenger side ground connection should all my sensors not ground on their pins?

  • Owner
30 minutes ago, Me78569 said:

I just ran out and tested the grounds on map and coolant and they are good to go so I am ruling out busted ground.

Mike,

Does the ground on the passenger battery that grounds the pcm and ecm also ground the sensors that are connected to the ECM?  

IE if I unplug the passenger side ground connection should all my sensors not ground on their pins?

No. That ground wire is a power ground.

As for the sensor grounds that is a floating ground that doesn't tie to body ground directly. So total to separate issues. ISX learned the hard way and figured he would join all ground to together ended up frying the PCM in result. So treat sensor ground and power ground as separates.

  • Author

ok thanks.

 

So another piece of the puzzle, the map plug shows 1.29v with no sensor connected coming from the ecm, rather than 5v.........  I am also getting a p0236 error with no quad plugged in which makes sense if the ecm is putting out 1.29v vs the 5ish it should be.......

  • Author

Map is weak

 

Coolant is not.

 

I THINK oil pressure is also, but I have not checked it, but it reads high pressure also.

Edited by Me78569

  • Owner

First off. The only sensors you need to make it run is Crank and Cam. MAP sensor will not prevent starting. So I would be aiming more towards the crank sensor and getting tach signal back. Which you'll need. Crank sensor drives the alternator and lift pump. You can drive it without a MAP sensor to get home in limp mode.

  • Author

So to update people as soon as I unplugged my new Oil pressure sensor I got 5v on my map. 

 

I am not going to tackle the crank sensor as the truck sitll won't start when hot, since it threw a crank code I figure it is worth a shot.

Crank sensor fixed my no start issue.  

 

Boost is back to reading right on my quadzilla so that is good.  I guess lesson learned....dont buy cheap oil pressure sensors.

  • Author

I really can't even begin to guess, but it also means that some of the sensors are on one 5v bus and others are on another........wrap your brain around that.

  • Owner

I'm going to assume the oil pressure, crank sensor and MAP sensor are all on the same 5 volt. I bet the oil pressure sensor was shorting out the 5V line caused loss of crank signal  ans well as the MAP codes.

Now the other 2 pin sensors I'm going to assume are on a totally different 5V system because of their nature. The 5V and sense is inside the ECM then bias from sensor ground with resistive sensor. The other system is a separated 5V and sensor set up so I can see thing being different.

  • Author

Very very valid thought.  

 

I would LOVE to have a spare ecm to pin out.

  • Owner

I would love to just play with SCIpod software and a programming cable. Yes, I still got it. Should get ahold of the gent that was doing that and see if we can jump into that project for education purpose. You know who I mean.

  • Author

I talked to him awhile ago and he didn't seem to remmeber much.

 

We might throw some money at him and see if he will sell it all to us.

Edited by Me78569