Hi all,
I have a 95 Ram 2500 and it won't always start if it sits too long.
I have to turn the key to the on position and wait 10-15 minutes,
sometimes longer before I hear chatter coming from the ignition coil.
I've change that but still no success. New batter, new starter. I
have an auto starter on it and its about 2 years old. No problems with
that unit and it still works. I heard that may be the problem but I
don't see how.
There was a former posting explaining the exact problem I have, but it
never showed the answer. Does anyone have any ideas on how to resolve
this ? It sounds common.
Here's the old thread...
My problem started as a nuisance and progressively worsened into a
disabled vehicle.
I have a 1994 Dodge B2500 Ram Van, 3.9 L, MPFI with 88k. A few months
ago it would occasionally crank excessively and finally fire up. I
found this got worse and more frequent. When cold, the fuel would
take some time to prime usually about 10 - 20 seconds. Once hot, the
motor would start on the first crank and continue to fire up through
out the day. The problem only occurred when the engine was cold.
I have since replaced the spark plugs, wires, air cleaner, PCV valve,
breather, distributor cap and rotor, and finally the fuel pump. I
also tested the operation of the MAP, Crankshaft postion sensor,
Camshaft position sensor, Throttle position sensor, and the Idle Air
control. This did not fix the problem. It may have created a new one.
Now it takes approximately 2- 10 minutes to prime the fuel. A
pressure tester shows 40 psi at the fuel rail once primed. Now,
however the autoshutdown and the fuel pump relays "chatter" for
several minutes. They toggle on and off very quickly - several times
per second. While this happens the fuel pressure climbs and when it
reaches 40 psi, the relays stop clicking and the ignition is enabled.
Once the relays stop making noise , the motor turns right over and
fires up easily. I tried to ground the relay PCM ground wire ( dk
blue with yellow stripe) directly to negative battery terminal. This
forced the fuel pump on, but would not allow me to start the engine.
I assume this is because although I had fuel pressure, I had no spark.
It would not fire until the jumper was disconnected and the relays
were allowed to continue chattering until they stopped.
The diagnostics show a code 12 - PCM voltage and a 45 overdrive
solenoid. I finally took it to the dealer who spent a few minute
with it but once the tech realized I had installed an aftermarket
alarm and remote starter, he would not investigate any further. I
realize the wiring modifications could cause the intermittent power
failure, but they're not new - they've been working fine for four
years. And if it was the cause why would it only occur when the
engine is cold? I have checked the wiring connections and all appear
OK. The dealer said I would have to disconnect the systems before
tehy will analyze any further. I am willing to do this but in the
meantime, it now stalls,
I've been able to live with the starting issue. It only takes a few
extra minutes to "prime the pump". Since this problem only occurs
after teh van sits for a long period of time, I've spent weeks trying
to troubleshoot it! Once the motor is warm it starts fine. But
now,perhaps I screwed up something while troubleshooting, the engine
won't accelerate smoothly past idle speed. If I give it a little gas
it sputters rather violently and then stalls. If I give it a lot of
gas it sputters and revs past the stalling point and then it runs OK.
(Well I have lost a lot of power now, and I keep the van in the
driveway until I can figure this mess out.) I have monitored the
voltage coming off the TPS and it consistenly increases from 0.6vdc,
when closed, up to 3.6 when the throttle is open. Even through the
stalling point. It seems to be vacuum related although vacuum is
steady at 17 in Hg. I relaize theis may be kind of low. It was 18 in
Hg when I first started messing with it, but it's been rock steady the
whole time.
I believe have two separate issues, although they may be related. I
thought if I spent the money, the dealer five star expert techs would
be able to tell me what the runnablity issue was with stalling above
idle speed. Unfortunately they won't go past the starting situation.
Why am I stalling?
Jon - 14 Dec 2006 16:48 GMT
Hello James,
Well, the good news is that the lady just picked up a Jeep -- and in
the recent past at the Jeep NG there was a discussion about chattering
fuel pump relays. I see you talk about the coil buzzing (haven't heard
that since I was in Gramp's antique engine shop), but your pasted
posting talks about relays -- so I'm going for the latter. I imagine
the info applies since we're under the D-C banner. Check it out:
http://groups.google.com/group/rec.autos.makers.jeep+willys/browse_thread/thread
/aaf26350d25ade2a
Also, James, are you saying that the fuel pump doesn't kick on for the
1-second or so priming when you first turn the key -- so it doesn't
kick on at all until the 10-15 min period has elapsed and the relay
chatter begins? Typically you can hear it with the door open for a
brief on-off cycle when you first turn the key from off to on. I think
this info will help greatly for myself and others grinding this one up.
Jon
> Hi all,
> I have a 95 Ram 2500 and it won't always start if it sits too long.
[quoted text clipped - 74 lines]
>
> Why am I stalling?