88 Caravan 3.0 V6 persistent code 13

Normally I'd say corrosion somewhere. Check your grounds, very important!

But in this case I'd go to a wrecking yard and get another engine controller just to be sure.

Ted

The engine controller *is* new. Only about 5 tanks of gas since dealer replacement.

Set of symptoms that prompted replacement is identical to current symptoms.

Good idea about checking the grounds. I am suspecting that giant

60-pin connector. The female terminals in that connector at the end of the wiring harness are round stamped metal and may be losing contact with the male pins on the controller module.

I wonder if those individual pins come out to be tightened up ...

The test wires I solder-spliced in were only one or two inches away from the 60 way junction so the next logical step would be to check the female pins on the connector itself. I only hope that they can pull out, be crimped with pliers and then be put back in.

Serial data somewhere on the mostly parallel 60-pin connector? Didn't know that. Why is there serial data and where would it be going?

"The Bathtub Admiral" wrote:

They can, but you'll need the proper tools otherwise you risk mangling the connectors and terminal block.

No, serial data transmitted by the PCM to the diagnostic connector located under the hood.

For diagnostic purposes, it goes to the diagnostic connector located on the left side of the engine compartment, slightly behind the battery, near the row of relays mounted to the inner fender. the data is meant to be retrieved by (initially) a Chrysler DRB type scan tool although there numerous other aftermarket scan tools available.

Has technical Service bulletin # 18-14-88 been performed?

How about TSB # 18-09-91?

These bulletins involve relocating the MAP sensor and installing a bleed hose assembly to the MAP vacuum harness and a purge jumper vacuum harness.

There should be/would have been a modification label attached somewhere underhood if the TSB was done at some previous point.

I made a Molex pin remover for PC power connectors once from brass tubing. However, I think I can use a sharp tool to bend the connector a bit in the housing to ensure contact.

It's an 88. I will buy a reader when I get a newer vehicle and I need to buy one. The vehicle might be too old for the newer code readers.

I don't hink either one has been performed. There wasn't anything plugging the hose or sensor at all.

It's a 1988 model and the MAP sensor is on the alternator bracket.

Be very careful, as these vehicles age, the connectors and terminal blocks get brittle. Terminal extraction tools can be gotten from any of the major tool suppliers or via the "Help" brand (Dorman) parts and accessories line that many national parts chains carry.

If you mean waiting and getting a scan tool to fit a 96 or newer vehicle, then yes, it most likely will *not* be capable of communicating with your 1988 MY vehicle. Check e-bay, there is lots of stuff for sale at pennies on the dollar compared to what it sold for new.

You'd be best served to visit a Chrysler or Dodge dealership and ask them to dig up the part numbers for or a copy of the latest TSB (18-09-91) and then see if the parts are still available, if so, install them before you dig any deeper. Once these TSBs were issued/ implimented, cronic /false code 13 problems pretty much evaporated. If the parts are no longer available new, a visit to a wrecking yard should yield everything you need. You're looking for a plastic fitting "Tee'd" into the MAP sensor hose, at the end of the "Tee" there is another plastic fitting (the bleed valve), the distance it is installed from the MAP sensor is critical so pay attention to how it's installed in the vacuum line.

I fixed my code 13 problem! Thanks to all and especially to Neil Nelson for inspiring me to test all the possibilities. We were ready to buy a near-new van but have to be in money-saving mode for awhile yet. You would not believe how relieved I am this problem is fixed and much money saved. History: After having the engine controller replaced, MAP sensor replaced, checking for vacuum leaks and checking ALL the relevant electrical connections ALL the way back to the module over literally months and months, it still complained of a non-responsive MAP sensor. Today I unplugged the 1/8" ID hose that the dealer had installed and blew into it. It was clear, but there was a hint of an obstruction. It was OIL! Cleaning it out with solvent fixed the problem like magic! Then I went by a wrecking yard to see if could could find the TSB parts mentioned but there weren't any to be seen. However, I did manage to see what the proper hose was and grabbed one. It was 1/2" ID at the manifold end and 1/4" at the MAP sensor end. I would have been problem-free longer had I the right tapered hose to start with but the dealer who replaced the controller just assumed a thin hose was all that was needed. So blow-by must have been depositing oil into the intake and it built up over weeks in the 1/8" (wrong) hose. I suspect this as after a highway run, a huge cloud comes out when restarted the next day. Never in town though. I suppose that the by-now-discontinued TSB part must have been some sort of oil trap to prevent gumming up the MAP sensor. That engine controller must check for a change in MAP voltage too early, before engine vacuum has had time to build up and get past the plug of oil, no matter how runny it was in there.

- gw

Neil Nelson wrote:

Glad to see that you got it fixed. Any time I replace a MAP sensor on a Chrysler product, I replace the entire hose/tube with a length of 1/4" vacuum hose.

Shame on the dealership that originally replaced the SMEC without doing a TSB search and/or just plain not recognising that this thing should have the bleed valve installed.

FWIW, a friend went thru similar > I fixed my code 13 problem! Thanks to all and especially to Neil

Thanks for the info.

My 88 New Yorker is starting to throw intermittent 13's at me. I will check the hose to the MAP sensor first !

Steve