Best way to test

[AlcHEmiE]

Best way to test charcoal filter cannister?

Whats the ebst way to test, or check the "charcoal filter cannister". I just replaced my EGR valve thismorning and it did nothing to my rough idle. Under hard acceloration the car is fine. But even under a steady pedel id seems to "Buck" a little.. I stumbled upon this comment below when i was searching the boards, and the my car is the same year and this describes my problems to a T. So i was wondering if anyone knew how to check this, and if this is the proper name for the part, so if it is indeed broken, i can replace it.


"Hi, I have a 91 that did the same thing and the problem to worse as time went along. Ultimately the engine ran so poorly I had to find the problem. The car had been in the Chevy garage and one private garage. In short, there is a charcoal filter cannister (spelling?) in the right rear quarter panel that handles fumes from the gas tank. The line from there goes forward to the fuel injection system. Anyway, the cannister had ruptured internally and the small granules from inside had completely filled the line going forward the sensor it attaches to. No codes showed up, but it sure caused my car to idle rough, steady pedal was rough and as I said enventually shut me down. I dont know if this applies to your 1987, but hope the info helps. Boz"

 

[Dougs91]

I believe you just replace the cannister, don't think you can test it. I'll check my Helm's tonite and let you know.

 

[AlcHEmiE]

Is that the correct name for it? I'm just using the term i heard in another thread. Im going to try and clean the TB and IAC because i also understand that the could fix it. These rough idle problems seem to be almost a "standard" on these C4's

 

[WNH]

going to try and clean the TB and IAC because i also understand that the could fix it. These rough idle problems seem to be almost a "standard" on these C4's

Same here, but I may stick a new IAC valve in while I have the TB off, costs about $45.

 

[AlcHEmiE]

$45? Wow.. Must be different than my 91, cheapest i can find is almost $70. But as far as the oil pressure goes, it stays between 45-50 for the first few minutes the car is running, then after i get to about 190° it drops into the 30's and at around 220° is drops into the low 20's to high teens.. After i clean the TB and IAC tomorrow i have to do an oil change anyway, so maybe i will just drop the pan and replace the oil pump.. I think its only like $40 or so..