Guests - If You want access to member only forums on HSO. You will gain access only when you Sign-in or Sign-Up on HotSpotOutdoors.

It's easy - LOOK UPPER right menu.

  • RECEIVE THE GIFTS MEMBERS SHARE WITH YOU HERE...THEN...CREATE SOMETHING TO ENCHANT OTHERS THAT YOU WANT TO SHARE

    You know what we all love...

    When you enchant people, you fill them with delight and yourself in return. Have Fun!!!

Sign in to follow this  
Cheeser

Problem with '91 Grand Prix

Recommended Posts

Hi guys -

OK, this one has me stumped, maybe one of you guys can help.

I have a 91 Pontiac Grand Prix LE, 3.1 V6 AT, PS, PB. I bought it this winter, and after checking it over I noticed that the twin electric fans weren't coming on. Well, it was winter and I don't think they come on until 210 degrees (or something like that) so I didn't worry too much about that, but I thought that they should kick on when I turn the A/C on max, correct? When I turned it to Max A/C, the compressor didn't engage, so I figured the system had a leak and I believe there is a pressure switch on the low side that won't engage the compressor unless there is 5-10 PSI in the system.

Anyways, I didn't worry too much about it, until now. On a whim, (my wife was complaining about it cry) I threw my gauge on it today, and low and behold the system is good on R-12. However, the A/C compressor won't engauge, and now I suspect the fans aren't coming on either. I was stuck in traffic on 494 the other day and I noticed that the temp climbed all the way to 225 and I didn't hear the fans. I checked all of the fuses in the fuse panel, as well as the ones on both the left and right service panels. I also replaced the relays. I have power at the relay plug, and when I bypass the relay it will turn the fans on and it will also engage the A/C compressor. What am I missing? Help! eek

Mark

Share this post


Link to post
Share on other sites

It is not uncommon for GM's to wait to turn the fan on until the temp reaches 220-230 degrees. It is important to use a scan tool to see what temps the are actually being read by the car.

What relay did you bypass?

Share this post


Link to post
Share on other sites

There are three relays; two for the fans, and one for the A/C compressor. I checked all three, one at a time of course.

If your wondering about the two sensor problem that commonly occurs on the 3.1 V6, I have replaced the sensor below the thermostat with a 2-wire sensor and compared the gauge reading to the scan tool - they are now within 1 or 2 degrees of one another, so I'm pretty sure the gauge is fairly accurate. I know what your saying about the fan coming on at high temps; the last corvette I worked on didn't come on until 232. Wow.

Share this post


Link to post
Share on other sites

I'm sure 4 will chime in sooner, but I would have to look at the diagram to give you some more pointers. If you bypassed the a/c relay than I would be concerned that the message is not getting to the relay. I'm not sure specifically how it is controlled but I might be suspicious of the control head. I won't be able to take a look until Monday but like I said when 4 sees this he will likely chime in with some specifics for you.

Share this post


Link to post
Share on other sites

Sorry I have been out all day, and I am on my laptop now, so I will check in the am.

Share this post


Link to post
Share on other sites

I would first start by checking to make sure you have power on 2 pins of each relay. Then jump a ground to the primary sides of the relays and see if the stuff works. In other words you want to do the ecm's job of grounding the relays. If it works then, you are down to a ecm input, a wire or a bad ecm.

Here are the diagrams.

coolingfans.jpg

accompressor.jpg

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.
Sign in to follow this  



  • Your Responses - Share & Have Fun :)

    • I shoot 2 steel all season long in an improved cyclinder choke . Satisfied with that. Have a buddy who shoots Black Cloud 3's with impressive results.
    • I stopped at Lowes yesterday and got restocked at 9.88 per 18.6 lb double pack. No limit indicated.  
    • I will have to find some more, cause we ate all of them! They were all connected on the bottom as they are supposed to be. I haven't seen a half-free or a Verpa yet this year and I have only seen a couple of Devil's urn's. The popple fuzz was covering everything this morning so they were a little difficult for me to see. Hopefully we get a shot of water with the lightning over night.
    • Good job!  I have never found any Blacks so they look a little different.  Can you take a picture of what they look like cut in half? They look a little scary like False Morel's 
    • I picked for about 2 hours this morning. I'm not exactly haw many I got but its enough for a couple meals. I'm going to chop some of these up and mix with some cream cheese, feta cheese and garlic chives and then stuff some chicken breasts and cook them on the grill. The little bit of rain that we got last week helped the shrooms pop but it really didn't do much else for the woods besides help the mosquito's hatch. There were so many they licked the bug spray off first then swarmed. I found the mushrooms all over, North, South, East and West facing hills. Normally spot 1 has the best results but this trip it was my second spot. All of them had pretty good size too. Only a few that were in direct sunlight were dried up otherwise they are very firm. Spot 1 is the left container. Don't worry, I use a mesh bag while I'm out in the woods!
    • Yup.... 6 & 4 for Lead.... 4 & 2 for steel
    • I ended up framing my house, putting on the T&G , and then spray foaming back against the interior, which may be why I am not seeing any movement... I also used pine vs cedar
    • I agree with the guy who agreed with the other guy.
    • Just wait till they come up with the remote submarine drone with 3d high resolution camera that can see through algae and milfoil and transmit to your eyewear in 3d.   I struggle with properly tying a berkley knot......
    • I agree with rundrave. #4 early and #2 shot later in year