1988 Dodge Caravan 3.0L Cranks - Won't Start

[Powerarranger]

I've just resumed working on my Caravan that died awhile back. Some helpful folks here gave me some good pointers! I was finally able to get codes from the computer and the important ones are 11 (no ignition reference signal) and 16 (loss of battery voltage detected while engine running).

Is there any other crank or cam position sensor other than the Hall effect sensor in the distributor on this engine (1988 3.0L)? I've checked the wiring harness which seems OK, grounds seem OK. Replaced the distributor, same codes. I'm going to check valve timing tomorrow to see if the timing belt jumped...

What does Code 16 really mean? The battery is fully charged and the engine cranks over just fine. All connections to the computer appear clean. "Loss of battery voltage detected while engine running" seems a little cryptic. Can anyone elaborate on this?

Anything else I'm missing here? Any advice would be greatly appreciated!

[1thunder]

i would say your timing belt is broken

[Powerarranger]

I'm going to pull the timing cover and check for that today. Since the engine has been cranking, I'm assuming that this is a non-interference engine (open valves don't collide with pistons when the T-belt breaks). Hopefully nothings's broken. If the belt is gone, this will be a relatively easy fix...

Thanks for the reply!

[yogi_123rd]

The 3.0L is a non-interference type engine.

Code 11: Did you check the crank position sensor? I think the fuel injection system also uses this signal too.

Code 16: You may want to check and clean the battery cables for corrosion build up and poor contact.

[Powerarranger]

Originally Posted by yogi_123rd

The 3.0L is a non-interference type engine.

Code 11: Did you check the crank position sensor? I think the fuel injection system also uses this signal too.

Code 16: You may want to check and clean the battery cables for corrosion build up and poor contact.

I checked the timing belt and it's in good shape. Valve and ignition timing are to spec. I don't think that there is another dedicated crank position sensor on this engine. I've looked in several service manuals and on the engine itself, and it appears that the Hall effect sensor and card in the distributor is the only source of crank/cam position data for the computer. I still could be wrong. The 3.3 has a crank position sensor on the bell housing and some also have a cam sensor up by the thermostat. This engine does not appear to have either of those sensors.

I'm consistently getting a code 16 (loss of battery voltage detected while engine running) and occasionally a code 11 (no ignition reference signal). I replaced the Hall effect sensor in the distributor and haven't seen code 11 in awhile.

All of the fusible links appear OK, fuses appear OK. Is there anything specific to look for with a code 11? I will take Yogi's advice and trace the battery cables. Anything else to look for while I'm doing that?

We're all stumped over here and running out of ideas. Keep 'em coming!

Thanks again!

[Dtech42]

Very often, a loss of battery voltage occurs from the battery ground cable. You might also check the engine ground for corrosion.

I have a Mopar 3.0 but I have not had any problem like this except a bad ground connection. It looked ok until I took it off, then it all broke apart.

The other explaination is that the ECM itself lost battery power. Check and clean all of the ECM connections (I think its a single harness close to the battery. The ECM is mounted inside the road-side fender, actually inside the air intake, unless it is different on 88s)

Good luck

[Powerarranger]

Originally Posted by Dtech42

Very often, a loss of battery voltage occurs from the battery ground cable. You might also check the engine ground for corrosion.

I have a Mopar 3.0 but I have not had any problem like this except a bad ground connection. It looked ok until I took it off, then it all broke apart.

The other explaination is that the ECM itself lost battery power. Check and clean all of the ECM connections (I think its a single harness close to the battery. The ECM is mounted inside the road-side fender, actually inside the air intake, unless it is different on 88s)

Good luck

I've checked the engine grounds and all looks good there. I'm going to trace the battery cables next. Possibly there's a corroded lead inside the sheathing.

If the ECM lost power, would it not be able to generate codes? I'm using dielectric grease to help get solid connections. Also checked for bent pins, etc.

The thing about this is how quickly it happened. I had just tuned it up (plugs, wires, cap rotor) and was driving it home when it just up and died. Someone said that they've seen the ECM get irreperably scrambled after a tune-up. Sounds like horse hockey to me. If the ECM was dead, it wouldn't generate any codes...or would it? The codes change, esp. after I disconnect the battery and get the battery disconnected code on the first crank. Any other ways to tell if the ECM is or isn't fried?

Thanks!

[jsr92643]

Had the same problem installed new coil then OK Hope it helps!!

[dj1111]

I had an '89 Caravan that one day ran fine going into the garage but would not start the next day. It was the 4 cyl version and I struggled and screwed around with everything to no avail. Had spark and gas but would not start. I was ready to call a tow truck when I was playing around with the fuel injector wire. Disconnected it and the thing started briefly then died. Reconnected the injector wire and it started but ran like crap. Was running very rich. I immediately drove it to the local Chrysler shop and they quickly diagnosed a bad map sensor. It ran perfect after that. In the subsequent years of owning it I replaced that sensor 3 more times. As soon as I'd notice the symptoms off to the parts store I'd go. Ran it until 199,000 miles then had to get rid of it. The original motor was getting real tired and would not pass emissions. Also had the original never repaired transmission.

[zulman]

Whats the story??