PDA

View Full Version : Interesting CEL on 80


timmbuck2
12-18-2008, 10:11 PM
OK, on my '97 80 I have had the check engine light on for a few months...finally got the time to go pull the codes. 146 (I think) something about the coolant temp changed too much, and the dreaded 401. I started researching the fixes, then last week in the middle of the cold snap, the CEL turned off. :confused: Yes, the light still works. So any ideas? I thought the CEL would stay on until it is reset??

Thanks

T

powderpig
12-19-2008, 05:51 AM
Yes Tim, that is what I have thought as well. Most codes are a 2 trip set and then need to be reset. But again, some (like the 02 sensor) have turned them off when all was good. I will spend a little time today with the book and see what I can come up with. Maybe you have a short in the wiring harness and it reset it self when the cold shrunk the cable into some metal. who know's, did the both codes go out at the same time or just the coolant temp code? If jsut coolant temp, then maybe just a ground issue. If both, then either a ground issue or a wiring harness issue.

FJBen
12-19-2008, 08:17 AM
Yeah I've had a strange code come up and go away. In Nebrasksa (which is odd) the code goes away and stays away no matter what type of driving, same for when we went to South Dakota on vacation.

As soon as we are back in Colorado, whithin a start or two the code comes back. Went and got it checked and they said P3011 or P0311...can't remember I"m getting old
1996 FZJ-80

It's says "02 sensor in Bank 1, slow to respond"

I"m guessing I need to just replace the O2 sensor, just odd that it goes away out of state. :confused:

timmbuck2
12-19-2008, 08:20 AM
Thanks guys...Robbie, the codes did not necessarily go away, just the light. I have not pulled the codes again since the light went out. I will try and do that soon.

Thanks!!!

T

nakman
12-19-2008, 08:23 AM
Timm I beat my head against the wall a few times with the 401, eventually did what I should have just done in the first place- I gave the truck to :robbie: and said make it stop. Year later, couldn't be happier.. :thumb: :bowdown:

60wag
03-22-2009, 08:19 AM
Yesterday I too got the P0401 EGR code. After reading a bunch of stuff on MUD, it appears that the code is usually related to a malfunction of the VSV behind the intake manifold. I might go through the easy checks on the EGR valve and the modulator but it appears that the VSV is usually the culprit. Is there any point in checking/cleaning the VSV or should I just replace it with a new one? What's a good price for a new VSV? TIA

60wag
03-25-2009, 11:17 AM
So I checked and cleaned the modulator and EGR valve and reset the light. It was gone for a couple of days but returned when coasting down Mashall Mesa on 36 into Boulder. Maybe after the light has been on for a week, I'll learn to ignore it but for now its bugging me. So how tough is it to service or replace the VSV hidden under the intake manifold? I can see it but haven't yet tried to remove it.

nuclearlemon
03-25-2009, 01:33 PM
So I checked and cleaned the modulator and EGR valve and reset the light. It was gone for a couple of days but returned when coasting down Mashall Mesa on 36 into Boulder. Maybe after the light has been on for a week, I'll learn to ignore it but for now its bugging me. So how tough is it to service or replace the VSV hidden under the intake manifold? I can see it but haven't yet tried to remove it.

I find it easier to leave the scangauge hooked up and just clear the codes as they come ;)

nakman
03-25-2009, 04:01 PM
I find it easier to leave the scangauge hooked up and just clear the codes as they come ;)

Yeah but when you're swapping your one good battery between all those trucks the codes kind of clear themselves anyway, don't they? :hill:

treerootCO
03-25-2009, 04:44 PM
I leave mine on to amuse LexusBen.

Crash
03-25-2009, 08:49 PM
I leave mine on to amuse LexusBen.

Have you noticed that LexusBen is no longer LexusBen? Now ThreeWheelBen!