92 Caravan 3.3L will not start

Hello,
Bought a used 92 Dodge Caravan 3.3 and started having problems with it
cutting off at stop lights and going into curves when I let off the gas.
Well whatever was going bad went bad and now the vehicle will not
start. The engine will turn over, but there is no power to coil pack or
to fuel pump. I can jump out one of the relays on driver side near
battery to make fuel pump come on, so I know the fuel pump will work. I
bought a Hayes manual, but it covers so many engine sizes and years.
There is not a wiring diagram in my manual for my needs of
troubleshooting. Does anyone know where I can get a schematic for the
electrical system for a 92 Dodge Caravan 3.3L? I have been through the
Hayes several times and have not found the information. Any help would
be appreciated. Thanks,
Brian

 

Yet they have the gall to label the book as a manual for your vehicle.
In any context other than aftermarket car manuals, that would be called
fraud.

It's just as well that Haynes does not have the schematics, because if
they did, they would be labeled "Typical" and one schematic would not be
specific to your vehicle, which, IMO, makes it worthless (kind of like
like using a roadmap of the highways between Denver and LA to try to get
from NYC to Chicago).

www.alldata.com - subscription to on-line access to good info. right out
of the factory manual, plus other information, including full TSB's and
the real (factory) schematics specific to your vehicle. $25 for a
year's subscription ($15 for subscriptions for renewal after first year
and/or any additional vehicles).

Bill Putney
(to reply by e-mail, replace the last letter of the alphabet in my
address with "x")

 

Quit trying to "jump" things. Your problem is most likely a dirty throttle
body. R&R the TB and clean it well including the AIS motor and pintle. You
may also have an EGR valve and it too may be malfunctioning. Neither of
these will throw a MIL but the EGR will store a code (if you have and EGR
valve). These are quite simple vehicles and trying to get deeper into very
minor things like this will only wreck it.
Larry

 

Brian,
My guess would be the EGR Valve. It should "actuate" during acceleraton and
"return to idle position" during deceleration.

Good Luck and do let us know what you find.

Jesse

 

When you jump the relay (I'm guessing it's the Auto Shutdown Relay) what
happens when you try to start up? The Auto Shutdown relay will interrupt
the circuit that energizes the fuel pump, the fuel injectors and, I believe,
the coil when it goes bad. Also, do you get any fault codes?

In my '88, that circuit has wiring that is green with a black stripe.

 

I have no fault codes, I have replaced the cam and crank sensors and
replacd the ASD relay. I also cleaned the throttle body as
recomended..all to no avail. I need a code scanner as it appears the
ASD appears to be looking like the guilty part, but don't want to
purchase one unless necessary.
Brian

 

From what you've written you also have no service manual. The Haynes book
is worse than worthless. You really need a *factory* service manual. They
are easy and relatively inexpensive to buy. You can get them new from the
dealer's parts counter, or used on Ebay.

This doesn't make sense...you've already replaced the ASD relay. That's
all there is to the ASD system...there is no such a thing as "the ASD".
Just the relay.

You don't need a code scanner. You've already checked for flash codes and
found none. (Is that because the "Check Engine" light flashes "12" and
then "55", or is it because the "Check Engine" light does not come on or
flash at all?)

At this point what you need is a multimeter. Use it to check the power and
ground at the ASD relay socket. With the engine being cranked, the socket
slot that mates with relay terminal 30 should show battery voltage when
you put a voltmeter across it and ground. The socket slots that mate with
relay terminals 85 and 86 should show battery voltage when you put a
voltmeter across them with the engine being cranked.

If not, then there's a problem in the wiring upstream of the relays or in
the SBEC (Single Board Engine Controller, engine control computer, ECU,
ECM). Corrosion can develop in the 60-pin connector to the SBEC, which is
at the left front corner of the engine bay, often accessible only by
removing the battery. The connector is held on with one 10mm screw. Loosen
the screw, remove the connector and inspect the pins and sockets for dirt
and corrosion. Sacrifice a pink pencil eraser to clean the pins pushwise.
Apply Ox-Gard or Noalox (sold at well-stocked hardware stores for working
with household aluminum wiring) liberally to the connector sockets, then
reinstall the connector, secure the screw and try again. If still no go,
do the same thing with the connectors at the firewall.

If still no go, it's probable you have one or more blown fusible links
upstream of the SBEC and relays. I had a '91 a few years back...drove in
from getting groceries, parked in the driveway, shut it off. Went to use
it 20 minutes later and it would crank endlessly but not start. The wires
to the heated O2 sensor had fallen out of their guide tube and onto the
hot exhaust manifold. When I turned on the ignition next, the direct short
to ground in the O2S heater circuit took out two fuselinks -- voila, no
power to the SBEC, no power to the ASD, no power to the fuel pump or
ignition.

I replaced the fuselinks in an unauthorized but effective manner, repaired
and rerouted the O2S harness, and the car started right up.

DS

 

I replaced the the engine control module and now have a functional
vehicle. There was direct voltage from the battery, but there was not a
9 vdc or 5 vdc present to operate the sensors. Alldata.com was my
greatest tool for repair.
Brian