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[oldguy44]

What are you using to read the data? An obdlink is just the translator, you will need either an app on a phone or a computer running one of the available programs to actually read data. There are a few such apps and programs out there including "torque"

I have a program from the OBD website on my old laptop. The one I use for all my car stuff. It has Mercedes and Beetle programs on it which is probably why it is constantly retching and hade to be replaced. When I put the LT in my Catalina I used a Howell wiring loom and they did a bench tune on the ECM. When it was in and running it had a CEL, I do not remember what the issue was I just remember that my cheapo scan tool could not deal with it. The obdlink program in my laptop took care of the issue. Only time I ever used it. Hopefully it will interface with the van. If not I will look into torque, thanks. Been busy with other issues hopefully will get back to the van next week.
Your remark about your suburban raises an interesting question. I had a 99 that ran as bad as the van. Any time I towed the boat to or from the lake house I used my wifes 06 Lexus hybrid because it had better towing capacity than the suburban! I am beginning to wonder if I am dealing with a California tuning issue (read California air resources board) I ran one of the LAPD repair shops from 80-90. WE had a bunch of late 80's Crown Vics with the carbureted 351 Windsor in them. That engine was not even supposed to be in the state but it was the only engine Ford had that would meet the required performance standards so LAPD quietly snuck them in.

You have a full size van, correct? Even if it is the small (Astro'ish) version, the 4.3 is not strong enough to drive under 2000 rpms without it feeling like dog chit. No amount of timing/tuning is going to help.

Granted 250 cubic inches (4.3) is not a big engine by todays standards but it still should be able to be tuned to run correctly. We ran a 250 straight six in a circle track car in hobby class for years and it was entirely capable of lighting the rear tires in first gear right off idle, even with a cam designed to run between 2500 and 6500, and they were not street tires. I refuse to believe that it is impossible to get better performance out of the van than what it currently has. I will guarantee that it can be done with a carburetor and a distributor, so I don't know why it can't be done with a computer. I just looked back and did not see a response from anyone in California. Hmmmmmmmmmmmmmmm

 

[BeXtreme]

I grew up in cali in the 90's. I left for the Army in the early 2000's and have never gone back. I doubt it is a "cali" issue. I agree, you should be able to get it to perform correctly.

 

[oldguy44]

OK this just keeps getting weirder and weirder. Had a busy week with the nonprofit I work for. One of the jobs took me near the repair shop of a friend of my son in law. I stopped by and he had a couple of minutes to plug in his professional grade scan tool and everything looks OK. HIs scan tool showed the idle timing at 21 degrees and in gear power breaking the timing held steady however 2 different timing lights showed the timing on my marks to be retarding. He had no explanation and did not have time to look at it so I gave up for the day.
Yesterday I went back to finish the last job and when I left the house the van ran differently. It is still not great but is definitely in the OK range for what I need it to do. Do these black boxes have a learn program in them? The van had not been running for a very long time before I got it. I do not know what that might mean in the overall view of what is going on but right now my attitude is it is feeling better I am feeling better leave well enough alone.
I do have a very negative effect on anything electronic so I might just chalk it up to that.

 

[oldguy44]

OK something to put into your memory banks. The van would run bad and then run good back and forth with no apparent pattern. To make a long story short I was in the van with my hearing aids on and heard a faint exhaust rattle. Crawled under the van and the Cat was rattling. Bang on the cat and you could hear in the exhaust note the timing back down. Finally something makes sense. Depending on the harmonics at any given time the cat rattles and the electronics read it as knock. Ordered a new cat and we will see, California cats are not cheap. Another reason to join everyone else and get out of this state.

It appears that my initial assessment was spot on, timing.

 

[L31MaxExpress]

OK something to put into your memory banks. The van would run bad and then run good back and forth with no apparent pattern. To make a long story short I was in the van with my hearing aids on and heard a faint exhaust rattle. Crawled under the van and the Cat was rattling. Bang on the cat and you could hear in the exhaust note the timing back down. Finally something makes sense. Depending on the harmonics at any given time the cat rattles and the electronics read it as knock. Ordered a new cat and we will see, California cats are not cheap. Another reason to join everyone else and get out of this state.

It appears that my initial assessment was spot on, timing.

As many of us pointed out, its not the PCM programming causing it either. Its a mechanical problem.

 

[BeXtreme]

OK something to put into your memory banks. The van would run bad and then run good back and forth with no apparent pattern. To make a long story short I was in the van with my hearing aids on and heard a faint exhaust rattle. Crawled under the van and the Cat was rattling. Bang on the cat and you could hear in the exhaust note the timing back down. Finally something makes sense. Depending on the harmonics at any given time the cat rattles and the electronics read it as knock. Ordered a new cat and we will see, California cats are not cheap. Another reason to join everyone else and get out of this state.

It appears that my initial assessment was spot on, timing.

Agree with L31... 100% not timing. Sounds like your CAT came apart and is clogged, which will cause huge backpressure and detonation issues. As was mentioned many times in this thread, no amount of cheating the computer would have fixed your issue. You could have put all that timing back in and all it's going to do is burn exhaust valves and maybe break a bunch of other stuff, all while still not running right.

Clogged CAT or knock sensor hits should have shown up on the scanner. You can monitor MAP sensor reading and see if you lose vacuum over time while cruising at a steady speed. If everything is working fine, vacuum should be high and steady. If backpressure is building, you will lose vacuum as you drive.

 

[oldguy44]

Let me clarify. Yes a mechanical issue affecting timing but the net result was retarded timing. I could tell that there was a timing issue right off the bat but did not know why. Now I know why. Not a clogged cat because that will not come and go but the guts are coming apart and rattling inside the housing causing the ECM to pull timing out of it. The issue of the timing retarding as you put power on it right off idle finally explained. I am not trying to say I was right you were wrong nanny nanny nanny, I only mention it because if it happened to me it could happen to someone else and knowledge of an out of the box issue could help someone else in the future.

 

[BeXtreme]

Let me clarify. Yes a mechanical issue affecting timing but the net result was retarded timing. I could tell that there was a timing issue right off the bat but did not know why. Now I know why. Not a clogged cat because that will not come and go but the guts are coming apart and rattling inside the housing causing the ECM to pull timing out of it. The issue of the timing retarding as you put power on it right off idle finally explained. I am not trying to say I was right you were wrong nanny nanny nanny, I only mention it because if it happened to me it could happen to someone else and knowledge of an out of the box issue could help someone else in the future.

Maybe its just a communication difference here, but it still comes across as a focus on timing. Timing is the symptom. You don't treat the symptom, you use it to find the actual cause. I'm only replying to this again to reiterate that an EFI engine will always be trying to pull timing like that for a reason, and just trying to force it to go back to the timing you want is almost never the answer. Connecting a reader to it right from the start and looking at what the ECM was seeing(as was suggested in the very first response to your thread) would have likely shown a high knock count and pointed you in the right direction.

For anyone finding this in the future, save yourself the headache and step one is almost always to connect a reader and check the data. Go from there. Knock count should be zero or single digits. O2 sensors should be fairly quickly fluctuating between 100mv and 800mv. CTS and TPS should be reasonable values.