Hey guys, got a weird issue here.

In my 94 Z28 after a few minutes of driving, around 10 or so, the SES light comes on as well as the fan on full blast, I can hear it from inside. The car is only around the 1/4 mark when this happens. Any ideas what it could be?

Thanks

 

No use speculating, have it scanned and pull the code(s).

 

Exactly what part of "The car is only around the 1/4 mark when this happens"? The coolant temp gauge?

The fans run because a code is being set that turns the fans on as a protective measure. Scan it.... you will have your answer.

 

Well I bought an Actron CP9145 scanner, this thing is awesome, I love this thing!



UPDATE 5/21/11:

Code 63 Right Oxygen Sensor (Bank 1 Error) - Replaced the drivers side (lol), need to still replace the passenger's side, need some help on how I should get up in there to take it out!


Thanks everybody for your help so far, greatly appreciate it.

 

Bank 1 is the driver's side.

 

Use Shoebox's code list. DTC 63 is for Bank 2 (passenger side) - open circuit

http://shbox.com/1/Dtcs.htm

 

Start by looking at the wires running down the inner fender that are wrapped with silver foil. When headers are present, the wires get cooked under this wrap and then split. I been there. BTW what does the car is at the 1/4 mark mean? Temperature?

 

Yeah temperature. Coolant temp is around 178-180 according to the scanner. Engine light just seems to come on after about 10-20 minutes of driving.

 

I know that this may sound crazy but check the fuse block under the hood. I think its location 7 ( in my Z28). Its a 20 amp fuse and see if its blown. This cured my problem

 

I'll check out the fuse for it first. So it's the Bank 2 oxygen sensor? Weird cause it said Bank 1. Thanks for your help guys.

 

I had the same thing happen - come on after a few minutes - fans on - temp not moving ever hotter than 1/4 - turned out to be the smog pump which the dealer replaced for free on a 1995 z28 because there was an open recall on it!

after that, SES light has never come on

 

Fuse is good.

 

You are both probably talking about the same thing. On a 94 fuse #7 in the under hood box is for the AIR pump. While the fuse is a common problem, it could also be a problem with the relay for the AIR pump. If it was related to the AIR pump, the SES light would come on as soon as he starts it. The diagnostic is a simple check of the signal circuit to the relay.

But there's no substitute for a scan that works.

 

If it's DTC 63, it's the other side. Pull the codes again to be sure.

 

Yeah it was 63, I'm just gonna have to do the passenger side as well. Any tips for getting to it? I took a look and it looks like a pain in the *** to get to.