i converted my carberator to tbi it runs great cold but as soon as it warms up when your driving it gets a real bad spark knock and starts to overheat anyone have any ideas thanks in advance

you got a knock sensor on the motor?

ya mounted on the head it has all the sensors that were on the donor truck

Did you use the distributor from the donor truck ?.

yep

shouldnt you be able to tap the block around the knock sensor and make it run different

got the timing set @ 0*? w/ the plug unpluged.

yep

Does it have an EGR system on it? If so maybe the orifice is too big and it is leaning out the fuel mixture too much? I think the ECM keeps the EGR valve closed until normal operating temp is reached.

Another possibility is the oxygen sensor is bad and causing trouble when the system goes to closed loop operation.

Do you have a vapor recovery system on it. That may have a vacuum leak in it.

it has the origanal egr valve but im not running the o2 sensor or the vapor canister but iv run them with out the 02 before it just runs a little rich. im going to put the vapor canistor on this weekend. where can i get a weld in fitting for a 02 sensor. thanks

oh and would be ok to mount the o2 sensor in the driver side header toward the end.

I believe you can get the fitting for the o2 sensor from an auto parts store or a muffler shop. I think you would be fine putting the o2 sensor in the collector on the drivers side. If you have long tube headers the sensor may cool off too much to work right. You might consider using a heated sensor, it may take care of that.

I wonder if the knock sensor mounted in the head may be giving you some trouble? The sensor is nothing more than a microphone that is tuned to pick up detonation. I wonder if it may be picking up too much valve train noise mounted in the head and confusing the knock sensor module? Is there any way you can move the knock sensor to the side of the block? It is normally screwed into the water jacket drain just above the oil pan near the center of the motor.

I don't know if this stuff will help or not though. It seems like your motor is way too lean by the sound of it, and I would think the above issues would make it run too rich. I hope you do not have a big vacuum leak (the bottom side of the intake manifold or the brake power booster maybe)? The cold enrichment programing may be enough to get it to run but the normal temperature operating programming may not be able to fuel it enough.

its running way to rich like it is now. i wil try to move the knock sensor to the side of the block and see what happens. thanks

tbi's tend to run way rich w/o an 02 sensor, there is a good possibility that you have fowled some, if not all of your spark plugs. Other common fuel mix problems stem from the map sensor and the IAC (idle air controller?), tey are fairly easy to check and it wouldn't hurt to clean the IAC on a 17 yr old motor.