new injector pump now problems

[jt]

97 k2500 replaced injector pump now wont idle or no tack and same codes come up

[a5150nut]

What are the codes?

[jt]

po251 po370

[racer55]

P0251 Injection Pump Cam System
P0370 Timing Reference High Resolution


Tach is run from the alternator so check connections and functions there.

Has the TDCO relearn been done?
KOKO procedure?
Scan tool TDCO value?

Is the optical sensor connected properly?

[greatwhite]

po251 po370

If the IP is new (as in new unit or fresh rebuild) and assuming everything is connected properly (especially the OS connector) then I'd say you have air in the pump.

Both these codes can be related to low fuel levels and getting air in the pump

Put a clear piece of line on the return and see if you get air bubbles or a clean stream of fuel.

Nothing to be done with air except keep bleeding it out.

These two codes also pop up with an OS failure, but very unlikely with a new pump.

As mentioned, tachometer is driven off an alternator signal and is unrelated to the IP. Unless you have the alt plug disconnected that is.

:)

[racer55]

Nothing to be done with air except keep bleeding it out.


Good point about air entry but something can be done.

Repair the leak in the fuel line between the fuel level in the tank and the LP.

The sending unit dip tube,rubber and metal lines as well as O-rings at fuel nut connections can all allow air entry on the suction side of the LP.

[greatwhite]

Good point about air entry but something can be done.

Repair the leak in the fuel line between the fuel level in the tank and the LP.

The sending unit dip tube,rubber and metal lines as well as O-rings at fuel nut connections can all allow air entry on the suction side of the LP.

Sure, if there is a leak.

OP made no reference to it being a problem prior to IP replacement so a slug of air in the pump seems to make sense.

If the clear line goes on and the bubbles don't go away, there's obviously a leak in the system somewhere that needs to be tracked down.

:cool: