Ok, here goes. My truck has a miss from time to time at an idle. It also has a stumble or hesitation when accelrating. I had to put a new motor in it 4500mi ago. Here is what else I have done to it trying to fix the problem. New fuel pump, still has good presure. New plugs, wires, cap, rotor, 2 times. New fuel injection spider kit, new coil, new fuel filter. I can not pick up any codes with modis snap on scanner, or the GM tech scanner. This all started about 2500mi after I put the motor in. Please help thank you. Paul

 

How many "long" trips have you taken with the new motor?.........reason........the computer needs to "relearn" with the new motor. also did you reset the the idle and timing using a scan tool? This is imparitive when you do a motor change, I just did one myself and had the same problems untill I had the idle/ timing reset. Basicly you set base timing and then go through several steps or rpm changes so the computer relearns the timing advance for the higher rpms.

 

my truck did the same, like when you accelerated hard it would just die unless you let go quick, the problem was that the timing chain was off, all i did was get some special tool it was like an offset wrench and readjust the timing chain from behind the distributor cap.

 

HUH????????....never heard of such a thing.....and its IMPOSSIBLE too!!!!!!!!!!!!

 

K, so after I fixed the timing chain with an allen wrench I changed the fuel pump with a letter opener. True story.

 

What kind of truck/engine are you talking about?

 

At hazard of highjacking the thread, I'd like to say that someone else already did...this morning I'm faced with some brakes that simply aren't behaving on my K2500. I've done Chev drums before, and haven't had a problem. My questions apply to a full-float 8-bolt rear hub...

1. - How tight should the retaining nut be on the outer bearing ?

2. How do I stop the son of a gun from overtightening after 100k. - it insists on burning a little bit every time I loosen it, it retightens...

 

Paul,

not sure if you got a new distributor with your new motor. I had to replace mine b/c the gear that engages the camshaft was worn, making the timing fluctuate a bit. It was missing once in a while at cruising speed, and gave me a P1345 trouble code. Once I replaced the distributor the trouble code and miss both went away.

 

Yeah Paul check that dist. gear. As far as timing chain, Im sure he means the timing, not timing chain.