Is it possible that the fuel sync was changed when i replaced the cap and rotor? Is there a hold down bolt to keep the distributor from turning? I emailed hughes and they suggested this but i dont think the distributor was moved.

 

I don't think fuel sync is the problem. Just changing the cap and rotor won't affect it at all.

Did swapping the injectors make a difference?

 

You said you replaced the cap, wires, plugs, and rotor. Just for fun, pull the CKP sensor from the distributor and inspect it for cracks or other slight damage. Also, pull it and check for grease or other debris in the pigtail. When I was reassembling my 5.2L build, I encountered misfires right away and discovered some gunk on the pigtail. I knew a guy who chased misfire issues for weeks until he pulled the CKP from his vehicle's distributor and noticed very fine cracks.

Sometimes, the actual cause is not obvious at all.

 

I haven't been able to drive it since i swapped injectors. I swapped them and got it back together, fired it up and it seemed to idle decent, but then i smelled raw fuel. Number 5 injector was leaking fuel where it goes into the fuel rail. I had to get new orings and throttle body gasket (ripped when i pulled the TB off). Also i discovered a coolant leak at the heater hose pipe that goes into the waterpump, the oring wasn't seated in the pump. I'll get it all back together and see if the injector swap made a difference. I noticed before that the injectors werent sitting straight down in the holes. Could that cause misfires and running rich?

Gary-L do you mean the camshaft position sensor in distributor?

 

Injectors are pretty much held in place by being clamped between the rail, and the manifold. Really not much wiggle room for them.

 

Yes. The CKP is the Camshaft Position Sensor. For future reference, always, always, ALWAYS replace the o-rings whenever the fuel rail is removed and injectors are serviced. It's cheap insurance to prevent a fuel leak. Be sure to lightly coat them with a bit of oil or some other lubricant to prevent tearing before they are installed.

 

I have it all back together. Coolant leak is fixed and it isnt spraying fuel anymore. I went for a drive and its showing p0132 and p0138. No more misfire codes. Its still idling rough and running very rich. When it goes into overdrive sometimes it stumbles and acts like its missing, but no misfire codes. when I slow down to a stop it stumbles and wants to die. Then when i accelerate it stumbles and doesnt want to go unless I accelerate hard. I did a compression test to

Cyl 1 - 160 dry 170 wet
Cyl 2 - 160 dry 165 wet
Cyl 3 - 165 dry 173 wet
Cyl 4 - 145 dry 155 wet
Cyl 5 - 158 dry 160 wet
Cyl 6 - 150 dry 158 wet
Cyl 7 - 153 dry 158 wet
Cyl 8 - 160 dry 165 wet

 

Unplug front O2 sensor, go for another drive. Any better?

 

when you did your intake swap, did you relocate the IAT to the air filter tube? the cooler air temp will fool the computer and add extra fuel, but, shouldn't cause a misfire! Also a few things to check, unplug your crank and cam sensors and get a small pick and try to close the gaps of the female side of the connectors, then get some dielectric grease to put in them before you plug them back in, also put some in your spark plug boots as well,i have also used the dielectric grease to the pcm connectors as well and has solved many of my drivability issues..

 

I did unplug the front o2 sensor, it didnt make a difference. Yes the iat in the intake tube. Many guys moved the iat to the intake tube and it didnt do anything for them so i don't think thats the problem. It only seems to run rough when its warmed up. I pulled the pcv line off the intake and it idled better. I'm gonna try completely resetting the ecm. Would a fuel sync problem cause it to run bad all the time or just when its warm?