1989 Iroc Camaro

[Albee44]

and I am back again

we can drive the camaro all over the place, for long or short periods of time,with no problem.........however, whenever we go up the incline roadway ( a hill or the mountain access as we call it) at the same spot everytime, the engine light comes on...(and I mean the exact same place everytime), we cleared the codes and drove it this evening, and on it came again, so we got the code.........it is showing code 45.

Does anyone have any rhyme or reason for this? What does this mean? Doesn't come on at any other time, only on the incline.

Any help once again will be appreciated.

[malletslinger]

Haynes Repair Manual says:
Code 45 = Rich exhaust...Rich condition caused by restricted air filter, fuel in evaporative canister or crankcase, malfunctioning carburetor/fuel injector, high fuel pressure, etc.; defective TPS; defective MAP; defective oxygen sensor; defective ECM

[silicon212]

It's most likely the air filter, so check that first. You should be able to see light through it.

[malletslinger]

Have you had a tune up lately? if not !!!
Check your air filter and evaporative canister filer(the canister is the large, black plastic cylinder with vacuum hoses connected at the top... it is held down by 2 or 3 screws around its base, remove screws, the filter is on the bottom. You can pick up a new filter at an autoparts store of your choice, but get the one that looks like the origional, it's round and looks like fiberglass).
Some fuel injector cleaner couldn't hurt eather...I use the stp additive.
But from what you have described, I think you can safely assume that the TPS, MAP, and ECM are just fine.

I'm guessing the problem is maintenance related and RELATIVELY small...just big enough for the computer to notice it under just the right conditions....HOWEVER...you should still fix the problem as soon as possible because when the ECM throws a code 45, the ECM operates in the open loop mode. It controls fuel delivery in accordance with a programmed default value insterd of feedback information from the oxygen sensor. This effects performance and economy.

[wrightz28]

Originally Posted by malletslinger

; defective oxygen sensor;

Or wiring

Try and recreate the problem on jack stnads or ramps, or heck even go to that particualr spot, open th hood and check to see if any of the mentioned sensor wires for that matter are grounding out (o2 being most likely). Could be a bare spot in the wire and on that particular incline, it's enough to ground the wire.

[Albee44]

ok, taking this one step at a time, this morning we removed the black canister and low and behold there is no white filter on the bottom, I guess there should be, so should I just replace this filter or the whole canister, and I was wondering out of this canister thing, should there be a faint smell of gas?? because I don't smell any at all, and I was wondering if the control valve is actually working......maybe that should be replaced as well??

thanks for your help

[malletslinger]

If it isnt there, then try cleaning it off, maybe try using an aircompressor at low pressure and blowing it off a little, put a filter on it and that will probably be fine.
I was just wondering, does this light always go off at the same place or just most of the time?
Did you check the air filter and spark plugs?

And as for what wrightZ28 said about a wire grounding out...that is a real possibility as well.
I there is only one wire that comes from the oxygen sensor, and that could be swaying toward the exhaust pip and making a slight connection. High voltage in this circuit can set code 45, and grounding out, if only for a millisecond, will set this code(but the sensor itself is probably fine).
So jack up the front of the car and check that first

[Albee44]

always at the same place, it's like it is timed to the second.....weird

will try cleaning it off and putting on the filter, and will check the wires.

will post the results

thanks