1997 GMC Yukon Timing
08-31-2009, 12:18 AM
#1
Staging Lane
Thread Starter
Join Date: Feb 2005
Posts: 95
Likes: 0
Received 0 Likes
on
0 Posts
1997 GMC Yukon Timing Hey all thanks in advance for reading and your responses and also I am not sure if this is the appropriate forum for this question if it isn't mods please take appropriate action. that being said here is the issue.
A family member has a 1997 GMC Yukon with a vortec 5.7 that we just had to replace the distributor. The distributor is set and the truck will start and run with a very jumpy idle and dies after 15-30 seconds. Obviously I am guessing that it is out of time. My question is it does appear to have any timing marks on the balancer and also doesn't have a distributor vacuum line that is typically removed when using a timing light. So what is my answer here??? does anyone know what the base timing is supposed to be and then the computer will pick up the rest??? Is there information that I am not stating that is needed for further assessment?? We have went through and made sure that all the vacuum lines have been reattached and the maf has also been reconnected as well...any help or direction would be appreciated thanks in advance again.
A family member has a 1997 GMC Yukon with a vortec 5.7 that we just had to replace the distributor. The distributor is set and the truck will start and run with a very jumpy idle and dies after 15-30 seconds. Obviously I am guessing that it is out of time. My question is it does appear to have any timing marks on the balancer and also doesn't have a distributor vacuum line that is typically removed when using a timing light. So what is my answer here??? does anyone know what the base timing is supposed to be and then the computer will pick up the rest??? Is there information that I am not stating that is needed for further assessment?? We have went through and made sure that all the vacuum lines have been reattached and the maf has also been reconnected as well...any help or direction would be appreciated thanks in advance again.
09-01-2009, 07:41 AM
#2
Staging Lane
Join Date: Feb 2009
Location: Baltimore
Posts: 53
Likes: 0
Received 0 Likes
on
0 Posts
it has the dist. cap that has the terminals coming out the sides, right? if so, then all of the timing advance is done through the ECM. You have to put #1 at TDC (compression stroke), and insert the distributor with the rotor and post on the cap being phased properly (basically aligned, not advanced or retarded). If it is not phased correctly, it will miss and run poorly.
You can try to loosen the distributor and rotate it slightly both ways and see if it fixes your problem. As for how to see if #1 is at TDC, you can put your finger over the spark
plug hole and when air starts to push out it is on the compression stroke. Then just use a long, thin screw driver to determine when the piston is at the top of its stroke. I'm sure a GM tech could provide a little more in depth information.
You can try to loosen the distributor and rotate it slightly both ways and see if it fixes your problem. As for how to see if #1 is at TDC, you can put your finger over the spark
plug hole and when air starts to push out it is on the compression stroke. Then just use a long, thin screw driver to determine when the piston is at the top of its stroke. I'm sure a GM tech could provide a little more in depth information.
