1998 Blazer/promblems with 4x4, no vacuum
blazee
12-19-2010, 07:23 PM
This is a repost of the first three posts in a thread that seems to have been removed from the database by a glitch. Please continue to offer assistance to our new member smanis94.
Tue, Dec 14, 2010 at 2:35 PM EST
I just bought this blazer, 4 wheel drive didn't work and I found a vacuum line loose on driver side firewall. I hooked it up and it started working but when I would drive on Interstate and go up incline and when I got to top of incline and let off gas it would make a whining noise and I would have to pull off and when I would come to almost a stop it would make a sound like it kicked out of 4 wheel drive and it would pop and it would do fine until I went up another incline. I read on this form about transfer vacuum switch, replaced it with new one and now I am not getting any vacuum to the actuator, any help would be greatly appreciated. I put a vacuum straight to the actuator because it snowed last night, will it hurt to drive it like this for a little while until I get it fixed? Do you think the new one could be bad or is there something else going on?
Tue, Dec 14, 2010 at 3:12 PM EST
you do not want to keep it in 4wd on dry pavement. the vechicle will "crow hop" When in 4wd the inside tire turns slower than the outside and will cause the vechicle to hop and thereofr damage the transfer case. You dont have any vacumn to the actuator under battery? remember you shld only have vacumn there while in 4wd. while in 2wd there should be no vacumn at idle. if so you have a bad switch. as far as the noise goes. sounds like the chain in the case. try to get all 4 wheels off the ground on ramps or jacks and see if you can pinpoint the noise
Tue, Dec 14, 2010 at 4:24 PM EST
There is no vacuum to actuator under battery and there is no vacuum in 4wd or 2wd. The sound it is making is not like a chain but it going in and out of 4wd. 4wd was working good until I changed the vacuum switch, other than it going in and out when I was on interstate on incline. When in 4 wheel still don't have vacuum.
Tue, Dec 14, 2010 at 2:35 PM EST
I just bought this blazer, 4 wheel drive didn't work and I found a vacuum line loose on driver side firewall. I hooked it up and it started working but when I would drive on Interstate and go up incline and when I got to top of incline and let off gas it would make a whining noise and I would have to pull off and when I would come to almost a stop it would make a sound like it kicked out of 4 wheel drive and it would pop and it would do fine until I went up another incline. I read on this form about transfer vacuum switch, replaced it with new one and now I am not getting any vacuum to the actuator, any help would be greatly appreciated. I put a vacuum straight to the actuator because it snowed last night, will it hurt to drive it like this for a little while until I get it fixed? Do you think the new one could be bad or is there something else going on?
Tue, Dec 14, 2010 at 3:12 PM EST
you do not want to keep it in 4wd on dry pavement. the vechicle will "crow hop" When in 4wd the inside tire turns slower than the outside and will cause the vechicle to hop and thereofr damage the transfer case. You dont have any vacumn to the actuator under battery? remember you shld only have vacumn there while in 4wd. while in 2wd there should be no vacumn at idle. if so you have a bad switch. as far as the noise goes. sounds like the chain in the case. try to get all 4 wheels off the ground on ramps or jacks and see if you can pinpoint the noise
Tue, Dec 14, 2010 at 4:24 PM EST
There is no vacuum to actuator under battery and there is no vacuum in 4wd or 2wd. The sound it is making is not like a chain but it going in and out of 4wd. 4wd was working good until I changed the vacuum switch, other than it going in and out when I was on interstate on incline. When in 4 wheel still don't have vacuum.
MT-2500
12-20-2010, 03:14 PM
This is a repost of the first three posts in a thread that seems to have been removed from the database by a glitch. Please continue to offer assistance to our new member smanis94.
Tue, Dec 14, 2010 at 2:35 PM EST
Tue, Dec 14, 2010 at 3:12 PM EST
Tue, Dec 14, 2010 at 4:24 PM EST
My old pc does things like that to.
I am a little lost on where the thread is at or how far along it is .
If smanis94. still needs help maybe he can start the thread again.
Tue, Dec 14, 2010 at 2:35 PM EST
Tue, Dec 14, 2010 at 3:12 PM EST
Tue, Dec 14, 2010 at 4:24 PM EST
My old pc does things like that to.
I am a little lost on where the thread is at or how far along it is .
If smanis94. still needs help maybe he can start the thread again.
Automotive Network, Inc., Copyright ©2025