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Opinions needed - Performed Optical Bump

Just went on a test drive without doing the relearn to see if the trans shifts and if I get a SES light.
no codes and no light but... no power ether! all I can get is 4lb of boost. I also noticed when letting off the fuel pedal and coasting down the off ramp the rpm surges from about 1k to 1300 until my speed is under 45 or so. weird. so I am going to do a relearn and try again to see if boost comes up and the surging stops.
 
Here are the results after I did the relearn. -.7 for the offset!
 

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So with no boost stepping on it hard should give you lots of black smoke. That junkyard PCM is likely a stock tune and won't give you very much boost. Pop the cover off your original one and see if the prom says anything on it.
 
Not a whole lot of black smoke but I did see it in my mirror lol

something else I noticed is with this pcm when I let off the throttle the rpm doesn’t just drop it gradually falls Even revving and letting off if gradually falls. With my pcm it would immediately drop to idle unless I was coming off the exit ramp it would go to about 900 until I pressed the brakes

I haven’t gone back out on the highway again yet since I did the relearn to see if the surging was gone when coming down the exit ramp with the JY pcm. Maybe I can just connect the vacuum pump directly to the actuator and try that.

I just went around the block after the relearn and punched it and saw only 4 lb boost again. I think I screwed up the solenoid because sitting in the driveway I can push the actuator by hand now where I couldn’t before
 
Dug out the power washer and gave her a bath before it got dark outside. Now she’s look’n mighty fine lol. Just hope she doesn’t fall apart after washing the tree sap and bubble gum off. :D

My in-laws had an old Ford Tempo that they’d swear every time it got washed something would break!!
 
I will have to try that. Just curious though. How does everyone else’s in an obd1 series do on the deceleration or revving and letting off. I honestly thought it was the “normal” for most gas vehicles ( I’m not that well versed with diesel) to have a delayed deceleration to idle rpm with no load. When I bought the truck the immediate fall to idle after blipping the throttle was one of the first things I noticed was different! When I say delayed, it’s pretty quick going back to idle but it’s enough to tell it’s different.

As for the wastegate solenoid, I’ve always gotten the code 78 when on the freeway, but it always kept full vacuum to the actuator so I’ve never bothered to replace it. After seeing a video clip of someone cleaning one with brake cleaner I thought I’d try it. Lol what have I got to loose. I’m sure I probably finished off the diaphragm inside it!
 
Well we made the trip
 

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How’s things going y’all!

even on vacation I couldn’t resist the addiction of working on my truck lol

I decided to pull the 9 blade fan and cheap Chinese clutch and reinstall my old one! The roar was just too much with the clutch not releasing!

In doing so I have two questions...

when I pulled the Chinese clutch off. With it y hands I worked it back n fourth several times and it broke loose to freewheel but would no do that installed on the truck!! What gives. Lol. Maybe it’s not a reverse rotation like it’s marked to be?

second question... at idle with the 9blade fan installed it wasn’t pulling enough air to make the condenser fans spin with the air being sucked through the front, with the 6blade fan it does. Is this something where the 9 blade fan is designed to pull more at a higher rpm but not as much at idle? Or a positioning thing? I did notice that the 6 blade fan sits slightly closer to the engine where the blades can be seen and the 9 blade sits further into the shroud about where the back side of the blade is somewhat even with the shroud.

anyhow I have the 6 blade fan and modified clutch installed since it was working fine and now I won’t have to listen to the constant roar. I’ll return the clutch I bought and plan to invest into the better water pump and a good clutch for the 9 blade fan.
 
Will L. said:
Fan shroud should cover half the blade. That is for any fan, any shroud.
Click to expand...
That’s probably why it wasn’t pulling more air That’s how the 6 blade fan seems to sit in the shroud. I guess once I get into doing the balanced pump which will probably have a spin-on thread and the good clutch I will have to check the alignment of the blades with the 9 blade fan. Although not sure what I’ll be able to do for adjusting it. Lol maybe a shroud for a newer model truck!

but no doubt that 9 blade fan was sucking lots of air once the engine rpm was anything over idle speed!
 
Hey guys! we made it back home today! the truck never missed a lick! ran perfect. although I discovered something on the AC. as long as I keep it under 65mph the AC cools real good. vent temps stay down to 45 but if I hit near 70 it slowly warms up to vent temps towards 60 degrees. It just might be still a little low on freon but overall runs great!. did my mileage going up there with 12.3 mpg. since I changed back to the old 6blade fan and a working clutch I need to go fill up and see how much of an improvement there was.
 
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