96 Sho Shuts off while driving... Brown Coolant.

[frankanthony]

I was wondering if anyone had any advice or experience with this issue... The car had shut off a few times in the past week but I hadn't had much time to investigate but when the low coolant light came on yesterday I decided it was time to get to work. The coolant light popped up on my way home so I stopped at a Pepboys I was near and grabbed some coolant (Peak long life 50/50) thinking I would top it off too safely make it home and park the vehicle. When I opened the reservoir I noticed that the coolant was a brown rusty color but it was full. So I have drained the coolant out of the radiator I couldn't find the block plugs and will try to locate those next time I get under it. Do you guys think this coolant issue could be related to the vehicle shutting off or do i just need a good flush and separate diagnosis?

BTW the coolant was flushed and refilled 12-10-2009 and the Vehicle just hit 110k miles yesterday.

 

[1998v8sho]

The coolant issue should not cause the car to shut off. As far as the coolant color being rusty brown, you may need to flush it out again. Something rusted is getting in the lines. Not good. You do not want the rust circulating through the engine.

Is the car shutting of on you at a light, a stop sign, or at idle? If that is the case, the Idle Air Control Valve might be on it's way out. I would also clean the MAF with an electrical parts cleaner. Try replacing the Idle Air Control Valve first and see if that resolves your issue. Then work on the MAF.

 

[frankanthony]

okay i will flush it again... the car has shut off 3 times and twice was backing out of a parking spot and once was pulling over to the side of the road... okay i will give the IACV and MAF a try thanks for your help.

 

[1998v8sho]

Good luck. Give an update as to how things turn out.

 

[frosho]

Does the coolant smell like oil, or have an oily film on it? How's your oil level?

 

[frankanthony]

Okay so the new IACV is installed and I haven't experienced a shut off as of yet but it was always imposible for me to purposely replicate...

I have re-drained the coolant and put in the Peak super flush solution and filled the rest up with water while the engine was running as the instructions said but the low coolant light will not shut off even after driving around today for about 45 mins or so and the reservoir level doesn't go down. The engine runs at normal temperature at all times.


@frosho As much as I remember I dont think it smelled like oil and it looked like it had an oily film when drained but I am not sure of that because I used the drain pan that I commonly use for oil changes. I actually was over due for an oil change and did that today while I was under there... less came out then normal though probably like 4.5 qts but I didn't measure before or after.

 

[1998v8sho]

The low coolant light is an easy sensor fix. The coolant level sensor might be clogged with the rust in the lines. Take it out and clean it with an electrical parts cleaner. If that does not help, time for a new one.

Is there any more rust in the coolant tank?

The V8 SHO should take about 6-7 Quarts of oil...I believe. Keep an eye on your oil level. Check it once a week to varify that you are not loosing, burning, or leaking oil.

 

[VortecGT]

I would also do a compression check for the head gaskets.

 

[1998v8sho]

Compression test would def. not hurt at all.
Good call VortecGT.

 

[frosho]

I would also do a compression check for the head gaskets.

This is why I was asking about the oil. Keep en eye on both the oil and the coolant to see if they're mixing and/or leaking somewhere.

 

[SHOZ123]

The coolant sensor is usually non repairable. They come with a new tank and a new cap. I would just get a new tank and be done with it.

Be sure to completely flush the coolant out. After the flush chemical drain and fill with distilled water. Drive a while and if that turns brown too add more flush chemical and repeat. Again fill with distilled and if it stays clean then drain and fill with a 50/50 mix.

If you mix your own coolant from 100% be sure to use distilled water when diluting it.

 

[frankanthony]

Okay guys thanks for the responses... Car has still not shut off since installing the IACV... I removed the Coolant reservoir and cleaned it out as best I could and the gunk was making the sensor float stick to the bottom... after spraying it out it works well and the low coolant light does not come on unless the coolant is actually low.... I have drained the coolant a few times now and its getting less brown every time I had the peak coolant flush in and drove around with it in for a few days like the instructions said and after filling it yesterday it is still looking green so I think I may be in the clear for with that issue. Should I still look into getting a compression test just to be safe?

 

[1998v8sho]

I would get the compression checked out just to make sure. Like I said it doesn't hurt. Glad things worked out well. Enjoy the car.