1988 Jeep Wagoneer 1988 Wagoneer starting problems

Tiny
HAMMER13
  • MEMBER
  • 1988 JEEP WAGONEER
  • 6 CYL
  • 4WD
  • AUTOMATIC
  • 175,000 MILES
My 1988 jeep wagoneer 6 cylinder has a random problem of not starting, usually after a trip somewhere like to the store or church. If you try again later (sometimes within 30 minutes, other times 1 - 3 hours later) it will usually start and runs fine. I have replaced the igintion module, fuel filter, cleaned the idle air control valve and EGR valve. I have read that the crank sensor is a problem on these models. Could that be the problem?
Sunday, June 6th, 2010 AT 5:27 PM

7 Replies

Tiny
OBXAUTOMEDIC
  • MECHANIC
  • 3,711 POSTS
Hello,

If I am not mistaken that year does not have a Crank or a Cam Sensor.

With what you describe it sounds like the Ignition Control Module which is located on the passenger side wheel well.

.
Was this
answer
helpful?
Yes
No
Sunday, June 6th, 2010 AT 8:09 PM
Tiny
OBXAUTOMEDIC
  • MECHANIC
  • 3,711 POSTS
Please Post responses here in forum and not by email.

Thanks

Ok, doesn't show a Crank Sensor on that year. Howerver, yes it can cause the problem, the knock sensor can also cause the problem.

.
Was this
answer
helpful?
Yes
No
Monday, June 7th, 2010 AT 3:53 PM
Tiny
OBXAUTOMEDIC
  • MECHANIC
  • 3,711 POSTS
Ok, Also when the vehicle wouldn't start did you check to see if you had spark going into the Cap and at the Plugs?

Also did you check for fuel if you have good spark?

.
Was this
answer
helpful?
Yes
No
Monday, June 7th, 2010 AT 4:02 PM
Tiny
OBXAUTOMEDIC
  • MECHANIC
  • 3,711 POSTS
Ok, according to specs the fuel pressure should be 31 psi and with vacuum line removed from regulator pressure should be 39 psi.

So, I would say you have a weak fuel pump.

Here is another test you can perform for comformation.

1. Remove cap from pressure test port in fuel rail. Connect Fuel Pressure Gauge (J-37730-1) to pressure fitting. Start vehicle. Pressure should be approximately 31 psi (2.7 kg/cm 2 ) with vacuum hose connected to pressure regulator.

2. Pressure should be 39 psi (2.74 kg/cm 2 ) with vacuum hose removed from regulator. If fuel pressure is not to specifications, check for kinks or restricting bends in fuel supply and return lines. Check fuel pump flow rate. Pump should deliver minimum of 1.06 quarts (one liter) of fuel per minute with fuel return line pinched off.

3. If flow is inadequate, check system for plugged fuel filter or filter sock. Fuel pump flow rate can be checked by connecting a hose to fuel test port on fuel rail and inserting other end in clean container.

4. To operate fuel pump, install a jumper wire into diagnostic connector terminals D1-5 and D1-6. Pinch off fuel return line to ensure that no fuel returns to fuel tank. If fuel pressure is still not to specifications and fuel flow is normal, replace regulator.

.
Was this
answer
helpful?
Yes
No
Friday, June 18th, 2010 AT 7:45 AM
Tiny
OBXAUTOMEDIC
  • MECHANIC
  • 3,711 POSTS
Ok, Check for loose or bad wires in relay harness.

If all appear tight and in good condition check numbers on relay then check other relays for matching numbers and swap them out. Then start vehicle and see what happens.

Also Please reply to this post and not by email.

.
Was this
answer
helpful?
Yes
No
Monday, June 21st, 2010 AT 7:29 PM
Tiny
HAMMER13
  • MEMBER
  • 3 POSTS
I could hear the EGR solenoid click when forcing the fuel pump relay to close so I tapped the EGR solenoid, fuel pump picked up and everything is working fine.

I replaced the crank sensor and the vehicle is running great! Much better than it has in several months.
Was this
answer
helpful?
Yes
No
Tuesday, June 22nd, 2010 AT 7:40 AM
Tiny
OBXAUTOMEDIC
  • MECHANIC
  • 3,711 POSTS
Great! Good Job.

If need anything else just ask.

.
Was this
answer
helpful?
Yes
No
Tuesday, June 22nd, 2010 AT 5:04 PM

Please login or register to post a reply.

Sponsored links