Buying 98 3.8 Firebird with problems, need advice

[sobek]

A good friend of mine has a 98, 3.8 Firebird for sale. It has 45,000 miles on it, was only driven by his mom daily to and from work, often was not driven at all for a couple of weeks (recently was parked for 3 months).
It's a red coupe with T-tops, nice condition in and outside, is "supposed" to have all the maintenance done on time - but she's an older lady so who knows..
Their is asking around $6500-$7000 for it, but...

After inspecting it here are a couple things I've noticed:
- when engine is cold I have to crank it for about 3-4seconds before it starts - kinda weird for a car with only this many miles
- after starting (cold) the idle doesn't settle at 1000 rpm, but goes up and down for up to 45 seconds (sometimes almost stalling) - not a huge thing, probably some tune up needed
- oil pressure on idle stays around 35-45 psi - is that normal? Even when I hit the gas hard - barely increases and never gets close to 60 psi
- And the last BIG thing that needs some more explanation:
Red, sticky, clay-like substance in the radiator. A LOT of it actually. The car does not overheat, but I guess thats a matter of time. My question is - what would be the most common cause of it?
The coolant level was very low when I looked at it, so was oil (but oil level still above minimum). She had a new heater core installed in October (just 4000 miles ago) + a "chemical" (whats that?) and full system flush - I saw the papers.
It makes sense that the heater core went bad - it got clogged, but since they did a flush, why haven't they diagnosed the problem?

So - how much time, pain and money should I expect to spend to bring it to "clean" condition?
Will just flushing help? And since I don't know the cause of coolant "gum-up" - do I need to have the engine taken apart, replace gaskets and do some very detailed cleaning to get rid of that stuff??
Apart from that, car and engine runs VERY well.
Any opinions are appreciated!
Thanks a lot!

[Savage Messiah]

Nothing there worries me except the oil PSI.

Most of that will be fixed with a tune up, and the gunk in the radiator is because someone once upon a time mixed Dexcool (the orange stuff, which came in the car) with the old green stuff.... mix the two and you get a mud filled coolant system. a good flush should take care of it.


The oil pressure though, even at 192k miles my 3.8 would be aroudn 60 psi most of the time.... myabe drop down a hair when stopped

[sobek]

Thanks for the reply,
But gunk in the radiator - i don't think anyone mixed green stuff with the red here. You have to remember it was flushed 4000 miles ago, and a new heater core was installed.
I've heard Dex-cool is known for eating gaskets... Would the rusty, clay-like substance be result of mixing with oil?

If I would assume that indeed somebody mixed the 2 coolant types - will just flushing help? I think that this stuff is everywhere, and it's really sticky and thick. what about the whole radiator, water pump, head and such - don't they need to be cleaned or replaced? Am I talking about taking head out and cleaning it?
If anyone has some experience with that stuff, please let me know.

Also - could the coolant problem be the reason why oil pressure is lower? Maybe it's just the sensor. If not - what could be causing oil pressure to be lower than usual?
Thanks for help!
S.

[scoobytuff]

I think a good flush will do the trick. Prestone makes a flush that comes in powder form. I've used it and its really good. It will actually eat bad spots out of an old radiator, you should not have this problem though. That usually only happens with very old radiators. A tune up should fix everything else, if not it could be the idle air control motor. Check engine light on? The car probably has these problems due to lack of driving or driving short distances. You should be fine on this purchase if this is a car you plan on keeping.

[sobek]

No "check engine" light and besides things mentioned, runs very good!

Actually - Prestone is the company that did previous flush - and on the receipt it says "System flush" and next line is "Chemical flush".
Is it possible they just added some chemical to the coolant but no actual full flush which caused the issue? (like I said - it was not driven much last winter).
Also after the car was sitting for 3 months, when my friend took it for a spin, it leaked a bit of coolant. After that there weren't any leaks at all.

What about the oil pressure? Could it be just sensor malfunction/error?

[Savage Messiah]

can try replacing the oil psi sensor, it's right above the oil filter. And believe me, my camaro's the same way, the gunk is a reaction of orange + green.


I've never heard of dex-cool eating gaskets.

[scoobytuff]

The stuff you want to get in called Prestone Heavy Duty Radiator Cleaner. It is also sold under GM part#12346500 and you can get it at the dealer. This would be a good time to replace your radiator cap and thermostat too. Here is a link that may be helpful. http://www.geocities.com/b_gillie/TSB990602012.htm
I know this is not the same application you have but the procedure is the same.

[stieh2000]

Would low oil lead to a drop in pressure

[Savage Messiah]

it could but i doubt it. More likely something to do with seals and/or the pump

[Orion2247]

The odd idle maybe a leak in the vacuum line. Also the difficulty starting may actually be from bad gas. Is it running on the gas that's been sitting in it for 3 months? Try filling it up with some new gas.

[gmack221]

The gunk in the radiator is most likely from the dexcool coolant mixed with green ... or someone could have put a stop leak in there ... in that case your looking at fixing the orig problem, new thermostat, and a flush & fill.

The low oil pressure could be from old oil, as oil gets dirty it thins out, hence why you have to change the oil. I haven't priced V6 models lately, but I'd see if you can pick up the car for under blue book price ... that way you can put some money into it & have a nice car for blue book price. Nothing sounds too expensive to fix, just issues to deal with when buying a used car ... good luck if you buy it, hope everything is as it seems.

[sobek]

Why new thermostat??
Wouldn't just flushing help?
S

[scoobytuff]

Some of the more caustic flushes may destroy the thermostsat, or any debris you knock loose could clog the passageway. Only replace it after you are completey done flushing your cooling system. If nothing else, replacing your thermostat in the process in cheap insurance against further problems and may spare you a future headache.

[izzydjinn]

The gunk youre talking about is normal, I have a 00 v6, and when I did my first flush, at first I kinda freaked out, probably thought the same as you, but after asking around (pitre pontiac in scottsdale) they said it was that the engine, radiator, and water pump settling. Also abut the oil pressure, one thing that I would do, and this is common sense on my part, add a bottle of gunk before an oil change and run for five mins. you might need to do this a couple of times to loosen any build up in the oil pan and oil pump. And after a couple of oil changes check for improvement, if that doesnt help, it might be the oil pump going bad. overall the car should be fine and last you for at least 200,xxx plus since mine has 143,xxx and still going strong with no major mechanical repairs.

[sobek]

Originally Posted by izzydjinn

common sense on my part, add a bottle of gunk before an oil change and run for five mins.

What do you mean by a bottle of gunk?