This is my first post so bear with me. I have read lots of posts in these forums but the issue I am having hasn't exactly crossed my path. I have done a lot of work on the van, but still have problems, and have codes that seem like they should have gone away with the replacement new sensors. So, the particulars: I have a full-sized E150 with a 4.9l engine with the EEC-IV control system. The van usually will not upshift automatically at first when D is engaged. The engine runs ok much of the time except erratically, sometimes, until the shift problem corrects itself. To use the van I start in D and soon manually engage 2nd since it will not upshift otherwise; the shift is nice and easy and it stays there for maybe 5 or so minutes. The CEL light is on. Then without really doing anything (it doesn't seem always to help if I rev the engine and speed up in 2nd- sometimes if I slow down the CEL light goes away- sometimes if I switch off the ignition momentarily it helps) the CEL light goes off and usually the engine will buck and backfire somewhat until I floor the throttle to clear the erratic running. After doing the hard acceleration (it doesn't take long at all), with the CEL light now off, the trans shifts quite normally with a tad of hard engagement from first to second, which always happens, and which is mitigated by easing off the throttle at the anticipated shift point. I had done the KOEO code reading some time ago and got codes for the MLPS- 634, the MAP sensor-126, and the EGR valve and EGR valve position sensors-332,334. So I replaced the MAP sensor and the MLPS switch with new units, and took apart the EGR valve, cleaned it (it was full of crud), put it back on and with mouth vacuum verified that it was moving/ working as the engine was running. Sucking on the line did slightly cause the engine to try to die. I put the trans in neutral and lined up the MLPS so the neutral line was perfectly lined up with the notch on the actuator. I still sometimes have problems with not being able to start up in neutral, sometimes not. I never have problems starting the engine. I later cleared the codes using a Sun reader to start fresh and got the same codes as above. I found two vacuum leaks; a broken small feed line to the AC dash control, and a larger black plastic hose going to the MAP sensor. I repaired those. No difference in codes, but the engine ran a little smoother. Some time ago I had a problem with two injectors not working so I replaced them and the engine had been running pretty good up to now, except during the erratic upshift period. I found that the tube to the EGR was leaking so I wrapped it in high temp rubber like tubing, and it got sealed ok. I tried to check for vacuum at the EGR, but could not feel any either at idle or under acceleration coming from the hose/ feed line from the solenoid. The MLPS connector looked clean and I put dielectric grease in there when I reconnected it. Some time ago, maybe a couple of years, because I really only drove the van about 2000 to 3000 miles in that time, I drained the ATF and put in new fluid, but it seemed to be overfilled for a while until finally I spent some time to get the level right as it is now. I did not drop the pan. The fluid that came out looked kinda burnt but now looks clean and pink. After the fluid change I was getting a shudder going up some hills under load so I put in some "Shudder stop" additive. It seemed to help some, but I still get the shudder at times. If I do I downshift and get up the hill, and on the level it shifts ok and stays in gear smoothly.
So I still have the initial failure to upshift, however once in a while it will show no CEL and shift normally, but usually will show the CEL and start the problem. Also sometimes the engine dies by itself as I am driving, usually decelerating; then I restart it and it usually runs and shifts ok. Funny thing is that once the CEL light goes out solving the no upshift problem it will come on later and usually stay on, but as long as I don't shut the engine off for more than a minute or so it will not shift poorly and it will restart and shift ok. If more than a minute it will go through the no upshift, light on, shortly after light out and then shift ok. The CEL light coming on after first start up and idle, if it did not come on right away at start up, affects the engine making it stumble somewhat, but usually not preventing a drive away and manual shift into second until the problem clears. The CEL light going on or off always affects the engine as if a spark plug was skipping or such except if the CEL comes on after I am running ok, but it will always respond to throttle except during the transition period when the engine may surge and die, but not stop. Another symptom which occurs at times is an increasing idle condition which can sometimes get fairly high revs going, particularly if I have to stop going down a steep incline. After I accelerate onto level again it runs ok. Sometimes I have to shut off the engine momentarily to curb the high revs, but usually on level at a light it will idle ok, except sometimes it dies. I have to run the van more to verify this condition still exists, since I cleaned the EGR and fixed some vacuum leaks.
So what I intend to do next is find out why there is no vacuum to the EGR valve and/ or that branch of the line, or how to get vacuum there and everywhere when it is supposed to be there- does the solenoid feed vacuum only under certain conditions; what other solenoids and/ or controls affect the vacuum supply. I read that there is a little hole for an alignment pin on the MLPS, but I don't remember seeing one, and I looked. I will probably try to change the alignment slightly. When I removed the old MLPS I measured the resistance with an Ohm meter and it was within specs. So after treating all the issues raised by the codes, except fully diagnosing the vacuum situation, I am at the same place I was months and dollars ago. I still have also the rear anti-lock warning light on- it is always on. If I run over the highway with the no upshift problem gone I get about 14 mpg.
I have done a lot of mechaniking over the years and the problem seems to be electrical in nature to my way of thinking. Another mechanic friend and I are going to pull the pan and change the filter. He thinks that is where the problem may be. But I would really, really like to get some input from the collective knowledge here on the forum. My other car is a Honda, and I am more experienced in foreign cars, and not much on automatic transmissions. I once had a Pontiac Bonneville that stopped shifting. I pulled it out on the ice, took it apart and rebuilt it. It still never shifted. Oh well. So please let me have it. I am all ears.

 

As far as the vacuum to the EGR valve it should only have vacuum on the it when the engine is warm and at mid throttle. No vacuum at idle or WOT.

As far as the transmission goes if you have to change the filter then it needs to be overhauled. The never should be anything in the filter unless the transmission is bad.
Changing The oil in the a high mile transmission will always make it work not as well as it did before you changed it. It has to do with stuff off the clutches in the oil that makes it work some better than fresh oil after a change.

 

Thanks for the EGR vacuum info and filter observations.. However, there are a number of other solenoids (how many?) I need to check, I presume. All I need to resolve is why it won't upshift. Some transient problem is preventing the shift. Hopefully someone can provide the clue as to why.

 

I did not see a VSS code but that could be because you didn't wait long enough to see the CM codes and you stopped after the KOEO codes.

 

I think I need to clear up all the codes, and fix the ABS warning light. Only trouble is, I dealt with the codes with new units and repair of the problems, but the codes are still coming the same. The reader I was using wasn't too clear on the codes following the KOEO. I will check into that. I wonder if there could be some corrosion or leaking in the PCM. Probably a good idea to open it up and look.