I know I have posted about this truck before but it is still giving me fits. I hate throwing parts at a truck to fix it so I really need some help. I have replaced the EGR on my truck and the EVP. I have also replaced the plugs, fuel and air filters, the computer, and EVR and TAD solenoids. And checked timing, fuel pressure etc. Now the problem. The truck idles well but pings and surges on acceleration when up to operating temp. If you jump in and go it runs great for about five stop and go blocks then acts like it is missing but idles good and free revs good. It only acts up under a load, also if you step on it the idle will hang up. I have pulled the IAC and there is no carbon build up and the plunger moves freely and the throttle body is clean. I have checks all the vac line and they look and hold vac well so what am I missing here. when i pulled the plugs they were all dirty from the plugged EGR, and the truck definately has more power but still acts up under a load. Help me out here guys. I love my Ford trucks but this one has a Gremlin in it.

 

gtrab a propane torch (don't lite it) and while the truck is running run the torch along the intake gaskets and vacuum lines. If the idle shoots upwards you have a leak




Jim

 

I didn't see you mention anything about changing the spark plug wires?? They have been known to cause this problem. especially the carbon filled type that expand and contract due to the temperature. Just athought.. Good luck!!

Regards,

Dukernc
1990 F-150 XLT Lariat 4X4 SB 5.0 EFI, 3.55LS, Modified AOD w/auxiliary cooler, cat back, all around farm

1999 F-350 CC Lariat Dually LB 7.3L, 6 speed, 4.10, Linex bed liner, 4" Magnaflow SST turboback exhaust w/5" tip

 

If not the wires then more than likely it is the ECT sensor, the one with two wires on it.
Any codes?

 

I pulled the cap and rotor off this morning the cap has carbon build up and the rotor looks pretty rough. Wires are only 6 months old and not cheapies either. I am having a brain toot what is an ECT sensor and where is it. no codes either

 

Ok with regards to the cap and rotor. When I did a complete tune up (truck had started to shudder) the cap and rotor both (aluminum) were badly pitted. So, I used only a bronze tipped (not aluminum) cap & rotor. Made a very big difference! Good luck..

 

Number 36 (ECT) in the diagram below:
http://i54.photobucket.com/albums/g9...tSensor302.jpg