1st Datamaster scan - help
Thread Starter
Instructor
Joined: Mar 2012
Posts: 170
Likes: 0
From: NH
1st Datamaster scan - help
I just got setup to do a scan with datamaster and I am really not sure what I am looking at. Is there a sticky or something to tell me what each value means and what I should expect? Also, I am not sure how to upload a file for people to look at. I took some data in my driveway in nuetral until the engine got to 240F (fans never came on). I had the issue with intermittant PCM sync, but I was able to find a couple threads on that so I will try the recommendations there.
I have a couple concerns:
1. My MAP is reading ~10-10.5 inHg at idle, when I put my vacuum gauge on the EGR port, I am reading ~19.5. Does this indicate something wrong with the MAP? I do have a high idle issue.
2. My ECM never goes into closed loop operation.
3. Where there are two columns, which one is pass/drivers side? My O2 sensor on the right column never changes value from 457mV.
4. The spark advance is 23, is that normal?
5. I immediately get a number of ~200 knock counts and then it doesnt change. I do have a DTC 43 that I am sorting through.
6. What should I expect for my IAC Position values? Starts off at 14 and goes to zero, it then jumps up to ~20 when the accelerator is depressed.
Thanks
I have a couple concerns:
1. My MAP is reading ~10-10.5 inHg at idle, when I put my vacuum gauge on the EGR port, I am reading ~19.5. Does this indicate something wrong with the MAP? I do have a high idle issue.
2. My ECM never goes into closed loop operation.
3. Where there are two columns, which one is pass/drivers side? My O2 sensor on the right column never changes value from 457mV.
4. The spark advance is 23, is that normal?
5. I immediately get a number of ~200 knock counts and then it doesnt change. I do have a DTC 43 that I am sorting through.
6. What should I expect for my IAC Position values? Starts off at 14 and goes to zero, it then jumps up to ~20 when the accelerator is depressed.
Thanks
Safety Car
Joined: Apr 2003
Posts: 3,793
Likes: 9
From: VA
What's the history on the car and problems?
I'd start by diagnosing the fans before you overheat.
O2 swap left and right sensors to determine if it's wiring or sensor.
Then fix the KS problem.
Don't worry about the other stuff until you have those things fixed.
I'd start by diagnosing the fans before you overheat.
O2 swap left and right sensors to determine if it's wiring or sensor.
Then fix the KS problem.
Don't worry about the other stuff until you have those things fixed.
Thread Starter
Instructor
Joined: Mar 2012
Posts: 170
Likes: 0
From: NH
Just bought it as a project so history is unknown. AIR system deleted, long tube header high flow cats to what looks like stock exhaust. A/C and also EGR deleted.
I spent some more time on it yesterday, looks like the relay connector got fried as well as the 5amp fuse. I have to check out the wiring as it has been monkeyed with. I ran another scan to see if I could lose the intermittant based on some comments here and both O2 sensors were responding. The system did go into closed loop, and I realized that the A in MAP is absolute so a ~10inHG value makes sense. I have a lot of intermittants and I basically traced the KS fault back to the ECM/PROM so looks like a new ECM is in my future. Just going to get a spare as I dont think the PROM has been tuned to delete the EGR/AIR/AC.
I agree, I got a little bit ahead of myself on the whole scanning idea. I just wanted to have a look at whats going on inside and got off track.
I spent some more time on it yesterday, looks like the relay connector got fried as well as the 5amp fuse. I have to check out the wiring as it has been monkeyed with. I ran another scan to see if I could lose the intermittant based on some comments here and both O2 sensors were responding. The system did go into closed loop, and I realized that the A in MAP is absolute so a ~10inHG value makes sense. I have a lot of intermittants and I basically traced the KS fault back to the ECM/PROM so looks like a new ECM is in my future. Just going to get a spare as I dont think the PROM has been tuned to delete the EGR/AIR/AC.
I agree, I got a little bit ahead of myself on the whole scanning idea. I just wanted to have a look at whats going on inside and got off track.
Safety Car
Joined: Apr 2003
Posts: 3,793
Likes: 9
From: VA
With long tubes on a pre-94 car you may have problems with it not going into / staying in closed loop because it has unheated O2s.
Solution is to add wiring for heaters and use the 94+ O2s.
Check if that has been done.
Solution is to add wiring for heaters and use the 94+ O2s.
Check if that has been done.
