Got a few 80 Blazer problems......Trouble-shooters: Please help!?!?!?!

[breakthru62]

Hi Guys! I'm a newbie and I really could use some help trouble-shooting.

I have an 80 Blazer: 4x4, 350, Auto trans (will post model tomorrow).
This Blazer is mostly stock, but I think it has a slight lift (will post specifics tomorrow).

Anyhow, I'm having a couple of problems. My rig will fire right up, but when I come to a stop, the motor starts ideling eratically. It idles where it should, but then it drops to the point I think it's going to die but then the idle goes back up to normal........up and down........up and down. It doesn't always do this, but it's becoming more frequent. Anyone know what might be going on here?????

Another problems is the tranny. When I start it up in the morning and put it in reverse from park, it doesn't engage. However, when I shift from park to drive and then to reverse, it engages and I can move. It also shifts fairly hard sometimes making a loud 'klunk' sound. What's going on here????

Also, I have a "squeak" coming from the rearend. The squeak is only present when the blazer is cold and going below 10mph (at least I can't hear it). For instance, when I back out of the driveway in the morning, the squeak gets higher and higher (the faster I go) but goes away after I reach a certain speed. I haven't noticed when taking of from stop after driving for a few minutes. Got any ideas???

One last thing.........My dash lights aren't working, but the blinkers and highbeam indicators are. I haven't checked the fuse yet ......could this be the problem??

Any and all help is greatly appreciated. I hope you guys can help.

Thanks,

Scott

 

[lectric80]

As far as most of your questions, in 80 it is most likely going to have a 350 trans since they discontinues the 400 that year for the Blazer.

The idle problem could be the module in the dist, dirty fuel filter, or probably a number of other issues. It could also be an issue with the torque converter, hence your second issue.

The tranny sounds to be worn out and may be on it's way out. Mine engages solidly into Reverse and Drive whether cold or hot.

Couldn't tell you what to look for on the squeak as I haven't seen this on mine.

 

[CB77GMC]

Check U-joints on rear D-shaft the "squeak" most times means one is on the way out.

 

[76zimmer]

ditto on the u-joint. And the trans may be getting worn out as well. What does the fluid look like? Should be medium red. Brown is worn parts, black is toast. How does the carb look, may need a rebuild for the idle problem. Maybe a vacuum leak too. I would start checking the simple stuff first.

 

[rcamacho]

For the transmission I'd start with a band adjustment and filter change. Just make sure you get the number of turns right on the bands else bad things happen.

 

[Seafarer76]

That squeak could also be your speedometer cable. One way to tell is if it is a rhythmic squeak, the speedometer needle will pulse in time with the squeak. You should definately crawl under the truck and check all your ujoints too. Move the front and rear driveshafts by hand and see if there is any play at the joints.

For your idle issue, check your engine vacuum and see if it is steady or erratic....you can also check the vacuum line to the tranny and make sure it isn't leaking.

 

[breakthru62]

Thanks guys. My wife wasn't suppose to take the Blazer this morning but did anyhow. So, I can't check this stuff today, but I will tomorrow. Thanks for throwing your ideas out there.......much appreciated.

I hope the tranny ain't going south......though it could explain why I got such a smoking deal. LoL......I thought I was good striking deals.
I've only had the Blazer for a couple of months, so I haven't had much time behind the wheel.

I will post my findings tomorrow. Please stick around for my findings.

Thanks again!!!!!

After thoughts: The carb looked like it was freshly rebuilt. I didn't look too hard, but that was my first impression.

The speedo is off something like 10 or 15mph. And it does sometimes jump around.

I will post more findings soon. Thanks.