engine trouble codes

[stratt134]

I just recently purchased a 98 GSX from out of state. I live in TX and I am trying to get the car registered here so I can get plates, etc.

I have a few problems with the car though. I took it to the expection shop but they found these codes:

P0505 - Idle Control System Malfunction
P0446 - EVAP Control System Vent Control Circuit Malfunction
P0340 - Camshaft Position Sensor Circuit Malfunction

the "Misfire Status" says complete on the test, but the car does have a big misfire/stumble. When you give it a lot of gas, it will miss/bog for a brief second maybe 1 or 2 times in each gear. For that reason I don't drive it hard right now. I just picked up new plugs and wires today and will install them tonight.

As far as the trouble codes and the missfire, I am very new to these cars/motors/ even turbos for that matter.

Thanks alot for any help,
Sean S.

 

[FusionTalon]

P0505 - Idle Control System Malfunction

This is mostlikley the idle control motor having problems. Im assuming the cars idle jumps?

P0446 - EVAP Control System Vent Control Circuit Malfunction

Something to do with emissions, if you have a OBDII handheld scanner or a buddy that does, clear this code and see if it comes back sometimes its a malfuction in a emission circuit that sets it off. Oxygen sensors can set it off also, or like in my dads Expedition, a blown fuse cause 4 emmision codes to show up.

P0340 - Camshaft Position Sensor Circuit Malfunction

This could also be a problem to your rough running motor. Its a sensor, and needs to be replaced, my moms Taurus had this problem, but for some reason it ran fine.

Also check your timing, see if that needs to be readjusted after the plugs and wires are in. Check intake for any holes because thier can mess the MAF up and cause a bad air/fuel misture.

I may be wrong, so if i am someone correct me, but its just something to start you off

 

[Siral3x]

P0505 - Idle Control System Malfunction. Your ISC/IAC is burnt, or stuck open.
If the car idles lower then 750-850rpm most likely is bad....I got some ISCs around...pm me if you need one.

 

[bomextalon]

the evap code is probally the valve not opening since the evap is for keeping you gas tank building up pressure.

 

[stratt134]

OK so I went and bought one of those little OBD2 reader things.

The lady at the inspection place cleared all the codes for me to see if the come back.

When I plugged the device in last night, it only had 2 codes showing up.

P0446 and P0505. The cam sensor code was gone (sucks cause that was the easiest fix for me)

I then cleared those codes and now I only have 1 code left - P0446 for the EVAP stuff.

How do I replace the "ISC/IAC" and where is it? Siral3X - I'll take one from you and send you a check or something?

I am about to go drive the car around with the OBD2 hooked up to see what else happens, and see if the plugs and wires I put in last night helped the missfire/stumble.

Thanks for everyone's help, I will have an update in about an hour or two

 

[FusionTalon]

go to this page http://www.ecmtogo.com/Idle Speed Controls.htm and scroll down, you will find the ISC motor information. I belive that site also sells them too so you can place your order there too..

Drive the car around for a bit, if the Cam position sensor is bad then it will eventually show up. Some of the systems wait for the fault to show up 6 times untill it triggers the CEL.

 

[stratt134]

OK so I put about 20 miles on it today. THE MISS IS GONE!!! Glad it only took plugs and wires.

For the first 15 miles, I only got the P0446 code. Then when I got home I checked it again before I turned it off, and the P0505 code is back. The code for the cam sensor hasn't come back yet, but I already ordered it and I am going to replace it anyways.

I will look into that website for the ISC monitor to fix the P0505 code...

Any suggestions on the P0446 code?

Thanks again,
Sean S.