1995 Dodge 1500 360 random no start/rough running

On Tue, 22 Mar 2011 15:11:35 -0700 (PDT), Nza
wrote:

>I have been working on my friend's truck here and there for a while
>now.
>He called me today and said that the truck crapped out and wouldn't
>restart..
>I went to look at it and had good fuel pressure but no spark.
>
>I gave the engine a reacharound and shook the harness going to the
>crank position sensor.
>The truck started right up, but randomly runs rough and still has
>random no start.
>
>The CPS affects the running of the engine in that either it works or
>it doesn't, correct?
>I could see the wiring being faulty, but I can't see it causing a
>rough running situation.
>Correct me if I am wrong, please!
>
>He did tell me that he has been running the tank pretty low lately,
>thanks to Obama, so trash in the fuel filter could be partially to
>blame for the roughness..
>
My CPS went but only when it was warmed up. Let it cool down and the
truck ran fine. It took a while before it through a code.

beekeep
 >> Stay informed about: 1995 Dodge 1500 360 random no start/rough running 

On Mar 22, 6:58 pm, Denny wrote:
> On Mar 22, 6:11 pm, Nza wrote:
>
>
>
> > I have been working on my friend's truck here and there for a while
> > now.
> > He called me today and said that the truck crapped out and wouldn't
> > restart..
> > I went to look at it and had good fuel pressure but no spark.
>
> > I gave the engine a reacharound and shook the harness going to the
> > crank position sensor.
> > The truck started right up, but randomly runs rough and still has
> > random no start.
>
> > The CPS affects the running of the engine in that either it works or
> > it doesn't, correct?
> > I could see the wiring being faulty, but I can't see it causing a
> > rough running situation.
> > Correct me if I am wrong, please!
>
> > He did tell me that he has been running the tank pretty low lately,
> > thanks to Obama, so trash in the fuel filter could be partially to
> > blame for the roughness..
>
> Your '95 has a cam and crank sensor. The pcm must see the crank sensor
> to start but will stay running off the cam sensor if the crank sensor
> fails after the engine is running.  The engine will run off the cam
> sensor but it won't want to idle very will. If you play with the gas
> to keep it running, it'll sound like the timing is off by about 20
> degrees.  If it dies, it will not restart till the key is turned
> completely off and then back on.
>
> You are correct that the sensor will either work or not.   The problem
> is the sensor can go from working to not working every few seconds.
> Trust me, that can drive a guy nuts trying to find it.    Alot of the
> time, the sensor works fine cold then acts up as it warms up.

Okay, that pretty much explains the symptoms I have seen. The
truck won't restart while it is rolling down the street, and the
driver is not about to lock the steering by turning the key off while
rolling anyway.. Both times I have tried to start it from key-
off position, it cranked up. The second time it started, then died,
then I didn't turn the key all the way off and it wouldn't restart.

I reckon I will R&R the crank position sensor and look for faulty
wiring.

Thanks!
 >> Stay informed about: 1995 Dodge 1500 360 random no start/rough running 

I assume there's no way to test the sensor with a VOM ?
I didn't find any obvious breaks in the wiring. Boy, that thing was
fun to reach!
 >> Stay informed about: 1995 Dodge 1500 360 random no start/rough running 

Well, I went ahead and took a chance and purchased a CPS from Advance
Auto...

Before I did that, however, I checked the resistance of the coil to
make sure that was not the problem.

Compared to removing the sensor, re-installing it was 10 times
harder.. however, it has been reinstalled and the truck runs better
than i have ever seen/heard it run before.. So, I think that was
definitely the problem. Thanks for the advice!

Hopefully someone will have the same problem and stumble upon this
thread!
 >> Stay informed about: 1995 Dodge 1500 360 random no start/rough running 

On Mar 23, 7:29 pm, Nza wrote:
> Well, I went ahead and took a chance and purchased a CPS from Advance
> Auto...
>
> Before I did that, however, I checked the resistance of the coil to
> make sure that was not the problem.
>
> Compared to removing the sensor, re-installing it was 10 times
> harder..   however, it has been reinstalled and the truck runs better
> than i have ever seen/heard it run before..   So, I think that was
> definitely the problem.       Thanks for the advice!
>
> Hopefully someone will have the same problem and stumble upon this
> thread!

Yep, they are really fun to get to. Glad it worked out....

Denny
 >> Stay informed about: 1995 Dodge 1500 360 random no start/rough running 

I was just thinking of something -- the guy has been running the oil
way way down in his truck..
I know on one of my Toyotas, if the ECU sees no indication of oil
pressure, it will shut off the fuel pump.

Maybe, just maybe, this is happening on his truck? Usually, I
check the fluids of any vehicle that I service, but I forgot to check
the crankcase oil this time.. I noticed while driving back to his
house the other day that the oil light kept coming on at idle.

I mentioned it to him the other day, and he reckoned he was about 2
quarts low... D'OH! Wouldn't surprise me if he still hasn't put
oil into the engine.
 >> Stay informed about: 1995 Dodge 1500 360 random no start/rough running 

On Mar 27, 11:54 am, "Steve W." wrote:
>
> 2 quarts low is a great way to kill an engine. Sounds more like the
> owner is a few quarts low as well. Tell him that one beer at a bar would
> pay for the oil he needs.
>
> And yes if the oil pressure drops it will shut down.


Ok, great! He called and I told him to add oil and let me know..
I'm amazed it hasn't destroyed itself yet.
 >> Stay informed about: 1995 Dodge 1500 360 random no start/rough running 

Nza wrote:
> I was just thinking of something -- the guy has been running the oil
> way way down in his truck..
> I know on one of my Toyotas, if the ECU sees no indication of oil
> pressure, it will shut off the fuel pump.
>
> Maybe, just maybe, this is happening on his truck? Usually, I
> check the fluids of any vehicle that I service, but I forgot to check
> the crankcase oil this time.. I noticed while driving back to his
> house the other day that the oil light kept coming on at idle.
>
> I mentioned it to him the other day, and he reckoned he was about 2
> quarts low... D'OH! Wouldn't surprise me if he still hasn't put
> oil into the engine.
>
>
>

2 quarts low is a great way to kill an engine. Sounds more like the
owner is a few quarts low as well. Tell him that one beer at a bar would
pay for the oil he needs.

And yes if the oil pressure drops it will shut down.

--
Steve W.
 >> Stay informed about: 1995 Dodge 1500 360 random no start/rough running 

ok, no change in the no start...

pbbtt
 >> Stay informed about: 1995 Dodge 1500 360 random no start/rough running 

On Mar 27, 4:27 pm, "Steve W." wrote:
>
> Got a scan tool?
>
> I would look and see what you have for sensor signals. Could be that the
> harness or connector has failed.
> Could also be something entirely new.
>
> I had a 360 a couple years ago that was running rough, would buck and
> act just like a timing problem. Turned out to be a bad O2 sensor that
> was an intermittent short. You could watch the ECM drop out just a split
> second before it acted up and the O2 sensor signal would drop to 0 at
> the same time. Has almost 130K on it so I swapped all of them and the
> owner is now very happy. He got a good running truck back and picked up
> 2mpg from what he had been getting. (all three sensors were going downhill)

no, I don't have a scan tool.. unfortunately.
I suspect you are on to the culprit even without checking it.

> How is this truck using oil? Burning or leaking?  If it's burning it the
> sensors are probably shot, they don't like oil burning...

The truck has 220K+ on it. I don't think it leaks much, but it puts
out a nice blue cloud when you first start it..
I went out to look at the truck today and couldn't find anything
obvious.... I did fiddle with the connector for the CPS, as well as
unplug and re-plug a few different sensors on the engine. I also
disconnected the battery and reconnected it after about 30 seconds,
thinking that might somehow do something..
The truck fired up and he drove it home.

I think I'm going to pass this one off to someone with a scan tool and
quit wasting time on it!
 >> Stay informed about: 1995 Dodge 1500 360 random no start/rough running 

Nza wrote:
> ok, no change in the no start...
>
> pbbtt

Got a scan tool?

I would look and see what you have for sensor signals. Could be that the
harness or connector has failed.
Could also be something entirely new.

I had a 360 a couple years ago that was running rough, would buck and
act just like a timing problem. Turned out to be a bad O2 sensor that
was an intermittent short. You could watch the ECM drop out just a split
second before it acted up and the O2 sensor signal would drop to 0 at
the same time. Has almost 130K on it so I swapped all of them and the
owner is now very happy. He got a good running truck back and picked up
2mpg from what he had been getting. (all three sensors were going downhill)

How is this truck using oil? Burning or leaking? If it's burning it the
sensors are probably shot, they don't like oil burning...

--
Steve W.
 >> Stay informed about: 1995 Dodge 1500 360 random no start/rough running 

Nza wrote:
> On Mar 27, 4:27 pm, "Steve W." wrote:
>> Got a scan tool?
>>
>> I would look and see what you have for sensor signals. Could be that the
>> harness or connector has failed.
>> Could also be something entirely new.
>>
>> I had a 360 a couple years ago that was running rough, would buck and
>> act just like a timing problem. Turned out to be a bad O2 sensor that
>> was an intermittent short. You could watch the ECM drop out just a split
>> second before it acted up and the O2 sensor signal would drop to 0 at
>> the same time. Has almost 130K on it so I swapped all of them and the
>> owner is now very happy. He got a good running truck back and picked up
>> 2mpg from what he had been getting. (all three sensors were going downhill)
>
> no, I don't have a scan tool.. unfortunately.
> I suspect you are on to the culprit even without checking it.

You can get a good deal on a Genisys unit on Ebay these days. I use mine
a LOT, as well as the Tech-2 and DRB and a couple others.
The investment isn't bad if you want to DIY and expect to work on your
own and help friends/others.
Make sure the one you get has ALL the cables and cards. The newest ones
are great and I plan on replacing my secong generation unit with a new
one or a Pegisys.

>
>> How is this truck using oil? Burning or leaking? If it's burning it the
>> sensors are probably shot, they don't like oil burning...
>
> The truck has 220K+ on it. I don't think it leaks much, but it puts
> out a nice blue cloud when you first start it..

Sounds like a candidate for the intake pan gasket repair, there is a TSB
on that one. Excessive oil burning at start and low vacuum while running.

> I went out to look at the truck today and couldn't find anything
> obvious.... I did fiddle with the connector for the CPS, as well as
> unplug and re-plug a few different sensors on the engine. I also
> disconnected the battery and reconnected it after about 30 seconds,
> thinking that might somehow do something..
> The truck fired up and he drove it home.

Same thing on the one I had in the shop. You could pull the ECM fuse and
it would start and run fine for a while.

>
> I think I'm going to pass this one off to someone with a scan tool and
> quit wasting time on it!

That or grab one of the cheaper tools that allows you to watch real time
data and see what the sensors are doing. I have an Actron unit that is
my loaner tool and it allows you to do limited testing and see most live
data.
http://www.actron.com/ (mine is older and no longer listed but the
newer ones do MUCH more anyway)

--
Steve W.
 >> Stay informed about: 1995 Dodge 1500 360 random no start/rough running 

On Mar 27, 3:15 pm, Nza wrote:
> ok, no change in the no start...
>
> pbbtt

You installed an aftermarket crank sensor right?? Try an OEM sensor, I
learned my lesson a long time ago about using aftermarket electronic
parts.

Denny
 >> Stay informed about: 1995 Dodge 1500 360 random no start/rough running