Hey everyone. This has actually happened before. I had changed out some parts (fuel pump, fuel filter, fuel pressure regulator, in tank fuel pump) and it had gone away. Yesterday I put my truck in reverse and it makes what I best describe as a knocking noise. Not a motor knock, I have heard that before in a few cars and I know its not that. It happens when I push on the gas and the truck hesitates. It is not only in reverse. It used to do this in drive as well. I also noticed a little hesitation on acceleration right before this happened yesterday but no knock. Any ideas??? I ran the codes and it is codes about the Gas recirculation system which was taken out. The same ones that have been there since I got the truck. There were no new codes.

PS I started it up after unloading the drywall in the bed and it didn't make a knock in drive or reverse.

 

I think I would check the condition of the motor mounts, transmission mount and the driveshaft universal joints. If 4x4 check that the front driveshaft slip joint is greased and moving freely.

 

Thanks for the reply. I'm pretty sure the motor mounts are good. I will def check the transmission mounts and drive shaft joints. Didn't even think that direction. Thanks alot! The slip joint is coming out of the transfer case right?

 

On the front driveshaft the slip joint is in the driveshaft itself, forward of where it bolts to the transfer case output flange. It is often neglected for grease.

 

I bet that is it. I will let you know after I get a chance to take a look. Thanks again.

 

Sounds like it's pinging to me. Spark knock, detonation, whatever you want to call it. Very well could be from deleting the EGR system. The computer adds 4* of spark advance when EGR is active, and if you're EGR is not really active and the computer adds the spark, you get ping. Try unplugging the spout connector and see if it still happens.

 

Thanks for the input. When you say the Spout connecter you are talking about the plug that sits from on/next to the intake manifold? This could also be an issue because I had put a new distributor in a while back. i went to set the timing and the timing pully has no markings on it at all. So i basicly have no idea of the timing. Should I just leave it unplugged and drive it?

 

Well yeah, that could be your whole problem right there. Your balancer will have timing marks on it, you just need to clean it and mark it with a marker. You need to find the spout connector, a small gray plug-in connector at the Dr. front corner of the intake, or in the driver's inner fender, by the data link connector. Take it out, set the timing to 10* and put it back in.

 

The spout should be right on the wiring for the distributor, hanging right next to it(at least on my '89 F150/302 it is). My '96 F350 was on left inner fender.

Take some light sand paper and wipe over the balancer and look for a "/" mark, as that is TDC. Unplug spout, set that for 10* and plug spout back in. Likely it's so far advanced it's detonating.

 

I may be crazy or blind, but I looked at the pully over and over and I see no marks what so ever. I have not tried to clean it, so I will give it a shot. Why would the timing suddenly change though? It has not done this knocking for 4 plus months since the new distributor was put in. I know exactly the plug you are talking about. I will disconnect it and see if that helps.

 

Ok I just took sand paper to the entire pully and I still do not see any lines. Any ideas? I see what looks like two rivet holes, but no timing marks.