new owner questions 92 b2600i

[codyblake]

Hey guys, I just bought a 92 b2600i with about 96000 miles on it. And I'm glad I found this site.

First off, the check engine light is constantly on. I first tried getting the code but when I turned the key to ON the engine light never turned off. I tried grounding it in a few different spots and still nothing. Then I took the computer off and checked it for damage. My untrained eye saw nothing, maybe a slight yellow gunk around one of them but that also appeared across the board - looked like some sort of sealing coat on some of the solder joints. Any ideas as to why I can't get a code? I've read something about the light just turning on for a maintanence check - I don't know when it turned on and I'm out of ideas.

Also, there is a very faint ticking sound coming from somewhere behind the center dash, though I'm not sure if thats exactly where, the acoustics are strange and the noise is so quiet I can't hear for sure where it comes from. I don't think it speeds up with the rpm's but it's hard to tell as the sound of the engine drowns it. Any ideas?

And the idle - I've read lots on the board about different idle problems but I don't think mine is as severe. I think it might actually be normal and I'm just not used to it. When I start the truck up it revs high for a while at idle, about 1200 and slowly comes down over the next ten minutes. Also when driving and shifting for the first ten minutes it seems to come down a bit slower then normal while between gears. Is this normal?

Lastly, and this proves my ignorance of mechanics and vehicles - the exhaust seems to smell a bit strong. It's not black and it might have something to do with the truck sitting for a few months. I'm pretty ignorant about fuel mixtures and how that effects the exhaust. Thats about all the info I have on that one.

Thanks for any and all help, suggestions, ideas and wisdom.

[Tyranitar]

The code is most likey a maintenance light. Perform all required tune up items as recommended in your manual for a vehicle with about 100,000 miles, the switch the maintenance trigger. It is located under the driver side dash. You will find a connector and 2 pigtails it can fit into. Just unplug it from the one and plug it into the other. The light will then go off. Make certain you perform the maintenace rather than just clearing the light, especially since you say that the exhaust smells. Everything else seems normal.

[originalmazdawg]

Tyr.. you dont have pictures of this plug to reset the maintenance light do you. I read that it was located on the backside of the instrument cluster, I pulled my cluster and did not find such a thing....hmmmm. You, however, said it was "under" the dash. Thats the first time I heard that.

[Tyranitar]

Ok, lay down and look up under the dash. It is not hard to find, just a single wire pigtail and 2 plugs that it can connect to. It is near the outside wall. I'm not sure where you read that it was behind the instrumnt cluster, but it is not, it is under the dash. I have reset mine many times.

[originalmazdawg]

You know what Tyra.. you are gonna laugh when I tell you where I read it.......one word......."Haynes". Man, I'll tell you what,I think I am gonna throw that @#$% book away, LOL!! I ended up taking the stupid light bulb out from behind the chk engine light just so it would pass inspection. My buddy and I hooked up a Snap-on scanner to it and we were not able to pull any codes out of it, "no codes stored". Thanks to you, (I think), I can now put that little bulb back so the light can do it's job, LOL!! Thanks again!!

[codyblake]

Thanks for the info. Glad to know the truck seems to be running alright for now. I'm off to do some maintainence.

[smuryof]

geeez I wish my 2600 only had 96000 on it - yours has its whole life ahead of it, buddy!

I notice an exhaust smell on mine, always have. Of course who knows if we're talking about the same sort of "strong exhaust" smell.

If you open your vent on the drivers side, does the ticking get any louder? If so I bet you have a small leak in your exh. manifold. I have that problem. Of course I've been driving it forever without worrying about it. I don't think I've seen any of these trucks without some sort of ticking that comes and goes.

[Tyranitar]

My exhaust manifold is also cracked. You may want to check yours, as it may be the source of the ticking.

[codyblake]

I checked the exhaust manifold quickly and saw no obvious problems, I'll have to do a more thorough check though.
The idle though still gives me worry. The past two mornings when I've started it the idle has gone as high as 2500 rpm and stayed there for about three minutes. When I give it a bit of gas it just revs higher and stays there. Putting it into gear, neutral and pressing the clutch in seem to have no effect, until I start driving then the engine revs normal, except for when I shift the rpm's return to their high state between gears. Maybe it's normal but combined with my gassy exhaust it's pretty unpleasant. This weekend I'll do a bunch of maintenance as far as filters and changing fluids, hopefully that will help.

[originalmazdawg]

could be the i.a.c. (idle air control valve/motor)