Hi all! I've been a long time lurker, and usually able to solve my problems by just browsing. But currently I am at a loss of what to think of my van and need some advice.

She ran perfectly up until a few days ago on a particularly colder day when she just refused to start. She cranks, but won't start. The gauges on the dash were all dead and I got the dreaded "No buS" on the odometer. I was already losing sunlight at the time so decided to leave it alone for the next day. The next day was much warmer, and she started right up, ran for about 20 minutes in idle, then shut herself off again. A couple hours later, tried again, and same thing, started right up, ran for about 20 minutes in idle, then shut herself off. Each time she shut down, it would revert back to gauges not working, and the codes 920, 921, then "No buS" would appear in the odometer.

We've checked the battery, fuses, wiring, the crankshaft position sensor, and there's no sign of corrosion or wear or tear, connections all seem clean. We removed the PCM and even peeked inside, and the jelly was intact, the circuit board seems to be intact.

Reattached the PCM the following day, reset it (disconnect negative battery and held key in on position for 10 minutes, etc), and she started up. But this time she only ran for maybe 3 minutes before shutting herself off. I checked for codes, there weren't any, but the check engine light came one. She started up again right after, but only lasted 5 minutes this time. Then it was back to codes 920, 921, 999 was new, then "No buS". The check engine light also started blinking before it disappeared. That was yesterday. There has been no change since.

What do you think? Is it the PCM? Is there something else I should look into before dropping $400 on a part that might not fix my problem? We replaced the ignition coil and distributor cap less than 2 years ago, could they have already gone bad? Any advice would be greatly appreciated!

 

I'd bet on the PCM. Get the number off of it and check Ebay -- you can usually get a used one for about 200.

 

Bad PCM.

 

agreed.


Also, did you get p0920 and p0.... etc.


Those are actually transmission selector faults, so Id double check there, but it does sound like the PCM. Ive gone through 2

 

if you can send your original pcm to the place in fla that you can get off internet. They fixed mine 300 bucks no need to reflash

 

Thanks everyone for the replies! I had a feeling that's what it was, but I guess just needed some reassurance before spending the money. I found a PCM on ebay for about 300, and they're only about an hour away from us so hopefully it'll get here within a day or two.

The codes I got didn't start with p0, but I did get 920 and then 921 before the "No buS" came on. Would that be any way related?

 

wow they are -- I had to look those up. They are actually bus/instrument clusters codes



920 The cluster is not receiving a vehicle speed message from the PCM.921 The cluster is not receiving a distance pulse message from the PCM.

 

That's what I found out when I did my own research as well. And the "No buS" seems to indicate there's no information being received from the PCM at all, if I'm reading correctly? Hopefully a replacement will fix my issue then. Fingers crossed! Thanks again!

 

yes and yw