Baja

AFC diaphram has been replaced.

gunracer1

pull the afc off, cover it with a shop rag and take it for a drive.

Lil Dog

I am with gunracer1, you have a problem with the AFC. Either they bound up the actuator with the install of the diaphram or something inside is binding. You have to be careful with installing springs or diaphrams that you ensure the AFC cam travels freely. This is also true with installing the AFC housing on the pump, you can have the AFC cam bind on the cam plate if you install the housing crooked.

Baja

I'm listening, I'm listening. I did have the diaphram replaced. It was given a vacuum check and failed, so it got replaced accordingly about one month ago. It made no difference in the performance at all. In fact, since then it has gotten worse! Since this has been such a slow process, can anything in the AFC get slowly bound up, or out of adjustment? If I pull off the AFC and cover it, what will I be looking for, I assume new performance, but what will this check tell me?
Thanks for all of your help.

gunracer1

it will tell you you need to look at the afc for it jambing up. just take it for a ride and see how it does, if it doesn't smoke pretty well you are missing fuel.

Ocmechanx

Alright you probably have already done this but I had a guy around here complainin about the same sort of thing and it ended up that everone he had taken it too had neglected to change the fuel filter and it was simply starving for fuel.

BC

Baja

OK, I got my truck back, and you are going to love this.
First, he could not get my plate to work, messing with the AFC all he could, but no luck. He then changed it and got it to run, setting the plate and starwheel. He does NOT really know what plate it is, just a Bosch. He says, "these work, trust me, the truck will say it all" okaaaaaaaayyyyy.......
Second he changed the timing of the IP. How, by removing the oil filler gizmo on the front cover, popping the gear from the tapered shaft, and rotating it, or the harmonic balancer, I am not sure, about 3/8th of a inch, after setting the engine @TDC. He has done this so many using a dial indicator, that he knows that 3/8" = about 2 degrees advance. okaaaaaaaaaayyyyyyyyyy.....
He increased the fuel pressure at the overflow valve by adding spacers behind the spring, increasing the compression of it. OK.
The funny thing is that all of this works. I cannot deny it, the truck absolutely runs much better. It cruises @70 much better than it ever did. The engine really comes on @1800rpm and stays alive longer, much better that ever before. It runs quiter.
I don't really know if I got ripped off. In some ways I did, I have no idea what he did, but in some ways I did not, the truck runs much better. I can only hope that this guy knew what he was doing!
I hope that he really torqued the timing gear nut!
My next question is how to get the engine to come alive at a lower rpm. Any ideas, thoughts?
I want to thank the DTR's who responded. I learned a lot through this, hopefully I will learn a lot more. Now I can get to work improving the truck instead of fixing it!

mr T

the guy sounds like a dork...no offence

cumminsdriver635

I cant believe it runs better. First of all; it doesent matter how many times he has done timing. Thats not how it should be done, and the overflow valve should have been REPLACED, not just rigged up to put out more pressure. Also; dont let him keep your #10 plate. Put that thing back in. The plate should have nothing at all to do with it unless the governor lever arm was hitting under the plate. Your wastegate line could possibly have a leak in it. If this happens your truck will drive like it has a valet switch on all the time, and it will just gradually pick up a little power as rpm's increase, but not have much pull/boost down low. With my Valet open(less power) I can still get 30psi, but I dont get over about 15 psi until after 2k rpm's. It actually does feel something like it doesent have a turbo. So regardless, I would check that out. The easiest way would be to take vise grips and clamp down tight on the rubber part of the hose going from the AFC to the turbo. Its good that its running better, I just feel like he didnt do it how it should have been done. And like was said; be sure and get your #10 back! Good luck.

Eric

rattlerbob5.9

Baja
I think most of your problem was related to timing when you had it checked before and it was found to be at 12.5 you should have told them to put it up to 15 . I feel this last guy just got lucky because the pop the gear and turn it 3/8
of an inch is a shot in the dark you might be up at 20+ degrees now! Overly high advance will kill your low end performance and can take out your headgasket due to excessively high cylinder pressure. With your mods timing at 15.5-16.5 should work good for you. Make sure whoever does it for you has a dial indicator with the proper delivery valve adapter and uses the CPL number from your engine data plate to check the chart for the proper amount of lift in MMeters this is the right way to set it . And by the way i was serious about the #10 plate.

Baja

I do have my plate back, I would never let it go. The mechanic did replace the overflow valve, I just did not say it very well.
No, I admit, I am not thrilled about his methods at all.
About 2 weeks ago, I pressurized the intercooler to 10psi. I did find a few small leaks in the line from the AFC to the turbo, now fixed. The repairs really never made a difference in performance. I will try the vise grip, easy and fast, no reason not to.
I still need to drive it a bit more to really figure out what he did, what the differences are. I will post them.
I had to laugh, my wife likes him, "he is intuitive, sort of like a cook who doesn't read the receipe". "Well", I say, "he can work on your car!"
I think that my whole problem was that the adjustments and governor arm were all AFU'd in the AFC. Odd thing is that the truck used to really go, it just slowly started to lose it, I would have never thought the AFC was the culprit.