OBD1 scanner not communicating
Thread Starter
7th Gear
Joined: Feb 2022
Posts: 7
Likes: 3
From: Vermont
OBD1 scanner not communicating
So after changing pretty much everything related to my issues this car still seems to be dumping fuel into the engine to the point that I saw flames in my rear view mirror, I did get a check engine light this time it was a code 23. haven't checked what that is yet, I may have walk away from this thing for a while before I go nuts, come back to it later, I did find a rebuilt prom chip, waiting on that before I continue. Any help would be helpful.
Pro
Joined: Jan 2022
Posts: 689
Likes: 245
From: Spokane Wa.
Have you checked the various grounds to make sure that you are getting continuity? My scanner notes that is one of the most common causes of no communication. If you have a FSM it will show you where they are. I believe there is a specific one for the ALDL terminal and others for the ECM and related modules.
Thread Starter
7th Gear
Joined: Feb 2022
Posts: 7
Likes: 3
From: Vermont
I did check clean and about ten different grounds I found in the FSM. I jumped A&B at plug and got a 23 code after seeing what that was I found that I left the intake air temp. sensor unplugged so I guess it is sending and reading codes in that manor. Decided to back track today and start over
, pulled all the new spark plugs and did a compression test and had about 160 on all cyl. Plugs were all pretty wet and black. tested all the injectors and had 16.2 ohms. tested fuel pressure turn key on and get 60 pounds for two secs. then drops to 40, when I start the car the pressure starts jumping quickly from 45 to 65 and when I shut it off it goes to 40 and holds for a few mins before slowly dropping . Any thing sound wrong with this picture, Thanks in advance.
, pulled all the new spark plugs and did a compression test and had about 160 on all cyl. Plugs were all pretty wet and black. tested all the injectors and had 16.2 ohms. tested fuel pressure turn key on and get 60 pounds for two secs. then drops to 40, when I start the car the pressure starts jumping quickly from 45 to 65 and when I shut it off it goes to 40 and holds for a few mins before slowly dropping . Any thing sound wrong with this picture, Thanks in advance.
Pro
Joined: Jan 2022
Posts: 689
Likes: 245
From: Spokane Wa.
Sounds to me that the pressure spike to 65 could be a problem. I believe that your system should be at 40 psi range and 65 seems too high. Have you tested or changed the fuel pressure regulator? But no comm with the scanner is strange also. What type of scanner are you using?
Thread Starter
7th Gear
Joined: Feb 2022
Posts: 7
Likes: 3
From: Vermont
I brought it to my buddy who owns a repair shop to scan it , and it would not scan, he has the latest snap on scanner, he thinks the EGR valve is bad and causing low vacuum which he said was at 9 in. and that controls the fuel pressure regulator, so I'm going to check into that tomorrow
