Keith

Dad and I swapped a HT383E into his 1999 3/4 ton OBS CCSB. All went well, it fired right up and we noticed an good difference from the old dead 350. The service engine light came on and we figured it was the broken coolant temperature sensor and replaced it. We unhooked the battery for two hours, swapped in the new sensor and the light came back on.

Today, dad went and had the truck scanned at autozone and came up with two codes:

P1345: Manufacturer Control Ignition System or Misfire
P0327: Knock Sensor Circuit Low input Bank 1 Sensor 1

I need help with the P1345.

About the P0327, can I Ohm out the knock sensor like on the NBS trucks and check for 100ohms across the sensor?

Whippled2dr

iTrader: (4)

For the P0327 code check the electrical connection on the knock sensor. Maybe clean the connector?

Check this link:
http://www.pacificp.com/forum/viewto...ht=p0327#34222

For the P1345, the distributor might be off a tooth.

Check link:
http://www.pacificp.com/forum/viewto...ht=p1345#41434

Keith

Thanks for the quick reply. I'll do the distributor when I change the oil tomorrow morning. I'll take another look at the connection at the sensor. I put two wraps of teflon tape on the sensor since they are pipe threads. Could that be the problem?

Keith

The distributor is in the right spot. I moved it one tooth CCW and it would not fire. Brought it back one tooth CW and it fired instantly. Hmmm...

Grumpy5.3

iTrader: (14)

can you read your CMP retard on the scan tool??? I know on stock engines it should be + or -2degrees from 0.

Keith

I'll have to go to autozone and see. What is my CMP?

Keith

Is there any possibility that the misfire could be caused by a bad crank sensor? The swap in the link had a bad one right from GM. I wonder if ours is like that too.

James B.

iTrader: (1)

The problem with the knock sensor can indeed be the ground. Use thread sealant, not teflon tape.

Keith

Quick update:

We swapped the new crank sensor for the old one, disconnected the battery and the service engine light was still on.

We then swapped in the old distributor and voila, the light went off. We went for a little drive and everything felt good, but...


When the accelerator is floored, the truck will downshift, but not accelerate. The RPMs will jump up and the truck won't get out of its own way. When the accelerator is let up, the truck upshifts, comes down in RPM and accelerates. It is almost like the transmission is slipping, but the RPMs don't go to redline, only to about 4,000 RPM. Everything at low throttle inputs feels stronger than the old 350. Only when the throttle is floored, does it act up.

James - Thanks for the input, I'll swap the tape for sealant when we flush the coolant in a little bit. Do you have any ideas about the other problem above?

Grumpy5.3

iTrader: (14)

sounds like you have a plugged fuel filter or stopped up cats....