Fuel Injector Voltage
#17
CF Veteran
Since you asked, it's an 8 channel oscilloscope that costs about 100 bucks (or there are ways to rent one). Anyway, you could test the performance of the CPS, CKS, injectors, and PCM (injector drivers). If you arbitrarily start replacing stuff, and the problem is the last shot of the parts cannon, you could end up dropping about 400 bucks.
Here's what a good injector looks like
and matching up CPS, CKS and one injector (the CKS is AFU cause the acquisition rate has been exceeded, but you get the idea):
Here's what a good injector looks like
and matching up CPS, CKS and one injector (the CKS is AFU cause the acquisition rate has been exceeded, but you get the idea):
The following users liked this post:
BlueRidgeMark (09-05-2019)
#18
CF Veteran
Here's a good CPS/CKS. I can build a good CPS/CKS/injector pulse if you end up going this route and need an example:
The following users liked this post:
BlueRidgeMark (09-05-2019)
#19
CF Veteran
Join Date: May 2012
Location: Lost in the wilds of Virginia
Posts: 7,964
Received 956 Likes
on
771 Posts
Year: 1998 Classic (I'll get it running soon....) and 02 Grand
Model: Cherokee (XJ)
Engine: 4.0
Really good stuff, Dave!
I may have to pick up one of those.... Do you have a model number for me?
I may have to pick up one of those.... Do you have a model number for me?
The following users liked this post:
BlueRidgeMark (09-05-2019)
#21
CF Veteran
The following users liked this post:
BlueRidgeMark (09-05-2019)
#22
Junior Member
Thread Starter
Join Date: Mar 2018
Location: ATL, GA
Posts: 45
Likes: 0
Received 1 Like
on
1 Post
Year: 1995
Model: Cherokee(XJ)
Engine: 4.0
Update: I spliced in the new injector pigtails and now I have no more check engine lights! My engine is also no longer running like dog sh$t. The issue must have just been some bad connections between the old cracked plugs and the injectors. The bad news is that I still have a little bit of a rough idle that gets really rough if I give it a little gas right at 1k rpms (runs smooth anywhere after 1k). I'm not sure if this issue is related or just something else that happened to come up at the same time. Going to start checking for vacuum leaks now.
#24
CF Veteran
Join Date: Mar 2016
Posts: 3,522
Received 654 Likes
on
558 Posts
Year: 96
Model: Cherokee (XJ)
Engine: 4.0
Update: I spliced in the new injector pigtails and now I have no more check engine lights! My engine is also no longer running like dog sh$t. The issue must have just been some bad connections between the old cracked plugs and the injectors. The bad news is that I still have a little bit of a rough idle that gets really rough if I give it a little gas right at 1k rpms (runs smooth anywhere after 1k). I'm not sure if this issue is related or just something else that happened to come up at the same time. Going to start checking for vacuum leaks now.
#25
CF Veteran
The bad news is that I still have a little bit of a rough idle that gets really rough if I give it a little gas right at 1k rpms (runs smooth anywhere after 1k). I'm not sure if this issue is related or just something else that happened to come up at the same time. Going to start checking for vacuum leaks now.
#26
CF Veteran
#29
CF Veteran
Join Date: Mar 2016
Posts: 3,522
Received 654 Likes
on
558 Posts
Year: 96
Model: Cherokee (XJ)
Engine: 4.0
I'm sure there is others who would appreciate being schooled up a little
#30
CF Veteran
IDK I have the CH3 parameters there (which isn't running) I'll have to rerun it. Should be in the neighborhood of about 100 tho.
Last edited by Dave51; 09-07-2019 at 05:40 AM.