Archived p1689 Misfire and possible solution

[rkressg]

Pin 13, 23 on the ecm?

They are for the DataLink Connection between the ECM and the Injector Pump.

My question is, has any body had any problems with getting DTC 1689 and the problem has revolved around a short in those wires. The wires are black and white respectively.

I plan on replacing replacing the wires between the injector pump to the ECM, the terminals on the ECM, and the connector on the injector pump.



The problem is a communication error between the ECM and the injector pump causing a misfire.

Fueling box has been removed along with other mods to return truck as close to stock as possible.



Has any body done this before to remedy this problem?

-Rich

 

[fest3er]

Originally posted by RGilbert
Pin 13, 23 on the ecm?
They are for the DataLink Connection between the ECM and the Injector Pump.
My question is, has any body had any problems with getting DTC 1689 and the problem has revolved around a short in those wires. The wires are black and white respectively.
I plan on replacing replacing the wires between the injector pump to the ECM, the terminals on the ECM, and the connector on the injector pump.

The problem is a communication error between the ECM and the injector pump causing a misfire.
Fueling box has been removed along with other mods to return truck as close to stock as possible.

Has any body done this before to remedy this problem?
-Rich

Merrick Cummings was having a similar problem. I suggested, when it happened again, to push the wires on the ECM connector more firnly into the injection pump. He reported that this tactic stopped the problem.

I think it may be faulty female 'receivers' in the VP or harness (whichever has the female connectors). A way to correct this problem might be to use a very fine pin (thinner than a fine sewing needle perhaps) and very gently and very slightly bend the contacts of the female receptors closer together. Note that I do not know if this can actually be done, but it should be worth investigating.

Fest3er

 

[MCummings]

LOL,



Fest, and Rich,



I'm just encountering this problem again.



I was having a heck of a time gttin my truck to run,, put, pushing n these pins fixed it,, now it's back again.



I'm gettina 1989, and 0237 (Low MAP). The 1689 is whippin' my butt though... . very low on power (I'd say ~80-100RWHP), very high EGT, and a lopey idle (to the point of dieing) until ~8MPH.



I'll look into these pins, and maybe, pushing on tehm this time will fix it again.....



Merrick

 

[rkressg]

Mcummings,

Check your MAP Sensor. I ended up replacing the MAP sensor, Engine Wiring Harness, and VP44. It took all three to make the problem go away.

My truck would had full power upto about 1600 rpm, then the fuel pump would just stop. The two wires that go from 1,2 pecm to 13,23 ecm should be twisted together, 2x per inch. They should also be properly shielded to eliminate any EMP interference. I have to think if I did anything else while troubleshooting.