ECM H31 code... momentary glitch or something on the horizon?
 

I was out today and parked to run into the store. When I restarted my 91 I got a "service engine soon." I drove for about 100 yards, turned it off and restarted and the DIC was clear. I drove home with no other issues.

I got home and pulled the codes. The car was clear except for the ECM module with a H31 meaning a "history" code for a cam sensor signal problem.

The car has been running great with no problems and I know that sometime sensors have "moments" and can throw an intermittent code then "return to normal." But (for those with experience) is this a sign of a future problem, should I inspect and/or begin looking for a cam sensor?

Thanks!

Re: ECM H31 code... momentary glitch or something on the horizon?
 

I had a couple of on/off cycles today- no lights. I also ran the diagnostics again and nothing popped up.

I think it was a momentary LOS (loss of Sh*t)

Re: ECM H31 code... momentary glitch or something on the horizon?
 

Bill,

Just watch for a while. If it recurs, might be starting to see signs of an aging cam position sensor or the weather pack connector may have an intermittent connection on the pigtail.

Steve

Sent from my SM-G950U using ZR-1 Net Registry mobile app

Re: ECM H31 code... momentary glitch or something on the horizon?
 

Thanks Steve- will do

Re: ECM H31 code... momentary glitch or something on the horizon?
 

My experience was intermittent codes then intermittent stop running when idling at a stoplight. Then I started looking for one to no avail until Phil re invented the cam sensor.

Re: ECM H31 code... momentary glitch or something on the horizon?
 

Can you please expand on that one?

Re: ECM H31 code... momentary glitch or something on the horizon?
 

Phil Wasinger is a brilliant engineer and I am using the prototype of camshaft sensor he developed 3 years ago. OEM or aftermarket ones are no longer manufactured. Do a search on this subject. There are a few threads.

My LT5 would just stop running. It would start right up again but I lost confidence on any trips out of town. Since replacement no problems.

Re: ECM H31 code... momentary glitch or something on the horizon?
 

Thanks Steve-- I reached out to Phil.

Re: ECM H31 code... momentary glitch or something on the horizon?
 

How can we contact Phil to buy sensor? I have same problem with my 90', engine stops, H31 code....

thank's