Hi all,
just found this forum and I've learned a lot about the Chevy Venture tonight, here in Europe it's called Trans sport.

I just bought a -97 which according to the previous owner was loosing cooland fluid so we suspected blown head gasket so the car was bought with that assumption. The prev owner just wanted to get rid of it so I got it dirt cheep considering it has just 130 000 km (~80 miles) and is in good shape in the body and internally.

When my father and myself went to look at it there was no battery so we couldn't start it but we checked the oil and coolant fluid which looked and smelled fine. No "mayo" could be seen neither on stick nor on cap and nothing floating in the refrigerator. The initial idea was to take it on a trailer as the prev owner said it couldn't be driven far, but since he also said that he had to add coolant fluid just every month or so it didn't seem too much. We were going to take it to my parents farm as there we have facilites for such work, my father and I have changed head gaskets on traktor and truck engines before.

Since the oil looked good we though to give it a try to drive it, since we don't have a car big enough to tow it on a trailer. So we bought a battery, brought bottles with water to fill it up when needed along the road and my father was driving behind with my other car in case we would need to tow.

The Chevy hadn't been started for 9 months so there was also a risk that something would have frozen during the winter but when I had installed the battery and cranked it started imediatly and run evenly without any bad noice nor smoke. After letting it run on idle for a few minutes we checked oil and coolant but they were fine.

We started to drive slowly to not stress it but it handled just fine. After 60 km on smaller roads driving 70-80 km/h we took a break and checked the oil and coolant again but it was fine. The coolant level was down at the MAX line as we had overfilled it before but any engine would have pushed out the excess water.

We had another 100 km to go so we kept off the high way to not stress and took the old main road instead but it behaved so well that after a while I went on the high way and it could easily maintain 120 km/h without effort. I kept an eye on the temperature gauge all the time and it kept at ~85 degrees celsius but when I stoped for a few minutes it went up to almost 100 degrees celcius but when driving it went down again. The red mark is at 110 degrees and it was never up there.

On arriving we let it idle for a while so it went back up to 100C and noticed that the electiric fans was running but not at any speed. Now I've learned that it is normal and the fans don't switch to high speed until 110C. We checked oil and coolant which still looked and smelled normal and there was no unusual noise or smell from the engine. The coolant level was still at MAX line, it had not changed for the last 100 km.

From our previous experience with blown head gaskets this behaviour doesn't fit that scenario. I've learned from this forum about the LIM gasket so that could be a possibility but doesn't that show by either smoke, water in the oil or exhaust in the coolant?

A friend had problems with his SAAB that it was loosing coolant and it tuned out to be a small leak in a hose that only came when the engine was warm and the system under preasure so it was really hard to find it, so that could be a possibility in my case also.

Anyway, my plan now is as follows:

Check oil again for any traces of coolant eventhough we haven't seen anything before. Is there a simple way to analyze that?
Check coolant. How to analyze if there are any fuel or exhaust traces in it?
Drive it for a while to see how fast it's loosing coolant, keeping an eye on the above as well as engine temperature.
Check fault codes from OBD-II, I've ordered an adapter for bluetooth.
I also observed some other issues:

The climate system is not working, the fan is running but no air is blowing. Is that controlled electrically or by vacum?
Fuel gauge is dead, it's fallen below empty mark. It doesn't even move during self test which I've understood it should so it seem to be either the gauge or PCM, not the sender.
Overhead display is dead
Radio display is dead
Power window on driver side has reversed operation, it goes down when up is pressed on the button and vice versa.
That's all I've discovered so far so I'm pretty satisfied. Any suggestions on the above is highly aprechiated.
Best regards
Sverker

For LIM leaks, look at ends of intake under the Power Steering pump and the other end for signs of wetness. Use good gaskets when reassembling, here in the US we have a Rubber over steel backing, I used those (FELPRO PERMADRY PLUS), and I love'd 'em.

AC/Heat Blower motor IS running, but not blowing air? Pull the glove box door down, the door in the back of G/B is for the air filter cartridges, check them....

My 97 the guage only moves when gas is used/added no self test.

As for the displays, check the dimmer switch on the dash.....

Hi Lester,
thanks for your input. No visible leaks found on LIM and it's keeping the coolant level, will continue to keep an eye on that.

Regarding the climate system I removed the control and there is no vacum in the hoses. From where does it take vacume for that? I changed the filters, the old ones were completly black and full of old leaves and other trash...

Regarding gas gauge, I filled the tank to full and then it moved up to empty position and when using the fuel it's moving below the empty position. I.e. the gauge is working, probably the problem is the sensor in the tank. Haven't looked at it yet but from what I understand it should give between 40 and 250 ohm depending on the level, or something like that.

The problem with the displays was not the dimmer, I had already checked that, but now all is working so I hope it keep that way...

Could be a bad ground on some of that stuff, The sender in the tank may be available separate from www.rockauto.com (http://www.rockauto.com), keep an EAGLE eye on the coolant level, it will bite ya. LIM is NOTORIOUS on these motors. IIRC the Vacume for the HVAC is taken from the top passenger rear intake manifold (behind alternator), the line crosses over the serp belt and off into ?

Yes, the sensor is availible on Rockauto as a kit, both standard and "extended length"

I'm keeping an eagle eye on both the coolant AND the engine oil and is prepared mentally that sooner or later the LIM, and possible the head gaskets needs to be replaced. I'm not too concerned about having to fill the coolant once in a while as long as it's not going into the oil as the latter is a major issue. So far I've been checking them after each time driving and it looks fine.

Last night I changed the engine oil, it was really black but nothing strange about it. No jelly, no water, no mayo, neither in the filter, everything looked just fine.

The vacum hose from intake had been disconnected from the split behind the battery so that was easy to fix. A/C is not working, will have it diagnosed.

About the fuel gauge, the comupter shows remaining range which seam to be correct so then the sensor in the tank must be ok or where does it take it's signal from?

Maybe the dash guage is toast. Had a guy with a bad guage and the motor was bad that drove the needle, he got on ebay and got 10 of the motors for $35 or so, GM wanted like $400 to rebuild the unit, he was quite glad to install his own motor (even tho he had to buy in minium quantity of 10.)

Acctually it seems that the motor is ok but just the needle that has been dislocated.

That ought to be a quick fix........ :-)