I hvae read all the threads I can find about this problem and it hasn't solved my issue.
I have an 86 305 TPI swapped into a 64 C10. New injectors, all new sensors except MAF, new throtlle body, new regulator , new fuel pump and filtere, Hansen chip in ECU, headers with heated o2,etc etc.
Truck starts and runs great. Once it is warmed up and I am coming to a stop it will always stall. Starts right back up and runs fine.I have noticed that just before ,or as it stalls the tach needle with jump up a bit.

Any help would be appreciated.

 

sounds like you never installed a vss

 

http://www.tpiparts.net/inc/sdetail/7586

 

You are correct I do not have a VSS.The wiring harness I used instructed me to ground circiut 437 on the ECU and I wouldn't need a VSS???
Can you comment please.

 

You don't say if this is maf or map, assuming that you grounded the p/n switch pin B10 on a 1227165 ecm the ecm thinks its in park or neutral and adds to the idle speed. You stated your running a hansen chip in the ecm. I have no idea what that is and if its based on stock gm programing 32, 32b or 6E. Since the ecm never sees that you are moving coming to a stop the ecm does not know the vehicle is moving and the sudden slowdown will cause a rpm to drop and may cause a stall. Install a vehicle speed sensor.

 

Thanks for the help. The swap the stock MAF sensor.I will install VSS as soon as I can figure how to install one. The speedo cable is a direct bolt in on the trans (T5) so I have to figure out if I can install the recommended VSS conversion up at the speedometer end.

Thanks again

 

not sure how you installed your fuel system but if it was a cavitation it would be noticed on hard cornering or hard take off. the vss needs to go to a buffer than optical out to the ecm. I have a buffer but no harness they can be found on ebay.

http://www.ebay.com/itm/VSS-Vehicle-...ef398a&vxp=mtr

 

I had this same problem and it was a bad MAF sensor.

 

Other possible solutions if stalling occurs after installing a VSS. This is straight out of my 86 GM Camaro Shop Manual

 

I appreciate the input but I am dealing with a situation that sees the engine die when rolling to a stop not a hesitaion or stumble.

 

From my experience, I had the same issue too. So what I did was switch out a few things and the problem went away. The things I did was replace MAF Sensor, installed a speedo cable (never had one), and I noticed that my Idle Air Control Valve had backed out and was creating a vacuum leak. After replacing, installing and retightening the valve, my iroc never died when I let off the pedal.

 

I had the exact same problem and it was the MAF.

 

Well a bunch of cash and effort to install a VSS in my truck.
Got it all completed and I still have stalling issues. I am beginning to think that the TPI install was a mistake! Don't know what to do next.

 

Check the IAC Valve. May be loose and creating a vacuum leak. Also you may want to remove the IAC and clean the port and needle with carb cleaner spray. When You reinstall the IAC, pull back the spring and turn the needle so that it screws into the motor. If its too far out, you can damage the IAC motor when you screw it in with the needle all the way out.

 

Thanks for the input. I have done exactly that twice...once with a new IAC. I have read every thread and tried everything suggested except replacing the ECU and still no results.
TPS, IAC, BOTH TEMP SENSOR, MAF, COIL, DIST, RELAYS WERE NEW, THROTTLE BODY WAS NEW,ETC ETC