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1995 Chevrolet C3500-HD

My 94 however is intake bolt which also doubles as alt bracket bolt and the passenger side goes to the coolant crossover. I'm going to be doing battery cable upgrades on the 94 so I think I'll move it to a regular intake bolt while I'm at it.IMG_20180927_183417.jpgIMG_20180927_183435.jpg
 
Moved the ground to a intake manifold bolt.
I replaced the eye ball inside the pump. I lost all the codes that go with it.
But, the coolant temp switch is bad. Will have to replace it before I can relearn TDC.
I am slowly knocking out the issues.
 
On too the next issue.
I got all codes cleared. But, I now have new ones. I have;

56 - injection pump calibration resistor error
88 - TDC offset error

I attempted a TDC relearn using GMTD scan. After following the instructions I got.
desired 8.6 - actual 8.7 - TDC 0
Then relearn and it drops too
desired 8.6 - actual 7.5 - TDC -2.02
Before I did anything I had around
desired 8.6 - actual 8.6 - TDC -1.89 - these numbers are a guess, I failed to copy them.

I guess my next step is too turn the pump?

I replaced both temp sensors and the plug on the one mounted in the cross over was bad.
It seems this truck is fighting me every step of the way.
 
IIRC you should be in the 3.5 range. I'd think your too far advanced. Is there a timing marks on the timing cover? Rule of thumb is to put the FSO vertical for a starting point.
 
OS?
FSO?
What are you asking?
I did nothing with the pump.
All I did was follow the instructions that GMTD Scan has on there website under FAQ.
 
OS is optical sensor, I thought you had changed it.
FSO is fuel shut off selenoid, round vertical cylinder on the IP
 
ok, the pmd was bad. I installed my spare and got rid of the other codes.
I moved the pump, it was way off. I aligned it with two marks already scribed in to both sides of the pump.
After that I got it set almost TDC perfect!
The spare FSO I had was bad. The one in the pump is good.

Now I just got to figure out why my boost is at O.50 psi per GMTD scan.
I also have the clutch on the A/C throwing sparks.
I can look at the bright side. I got the motor running good with no codes!!!
 
I’m thinking that I read in the past that you have to calibrate or do something to the optical sensor when you replace it. I’m assuming that GMTD software might could do it if it needs it but I’m not sure.

Since it’s running good you might not have to do anything to it.
 
I’m thinking that I read in the past that you have to calibrate or do something to the optical sensor when you replace it. I’m assuming that GMTD software might could do it if it needs it but I’m not sure.

Since it’s running good you might not have to do anything to it.

That is why I did the TDCO relearn using the GMTD Scan. It is running better, just got to figure out why the turbo is not working.
 
I am not sure how to do that. I will play with it tonight. Thanks!
What is the fuel rate at idle? If the OS is set in correctly, the fuel rate should be around 7-8mm3 of fuel iirc at a hot idle. If the fuel rate os off, you will have to bump the OS until it reads correct, then you have to reset your pump.
 
What is the fuel rate at idle? If the OS is set in correctly, the fuel rate should be around 7-8mm3 of fuel iirc at a hot idle. If the fuel rate os off, you will have to bump the OS until it reads correct, then you have to reset your pump.

I have 10mm3 of fuel at 700rpm. So to fix this I have to move the eye ball(OS)?
I don't see a way to do this on GMTD Scan.
Is relearning the TDC resetting the pump?
 
Relearning is resetting the pump. You basically have done an optic bump. Could end up with a touchy throttle. Since you know you have 10mm of fuel you now have to physically move the OS and then recheck. You'll probably be sick and tired of moving and checking by the time you're done.
 
Does anybody know which direction of move does + or - ??
I was already tired before I installed the new OS.
Actually throttle is not that bad. Not having a turbo sux!
 
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