How do you know a TFI may be going out?

[88 Fox GT]

This isn't my Mustang, but rather my 5.0 truck. It won't run. I drove it the other day and it ran just fine all the way to point A to B and back. I parked it in front of my driveway and when I went to start it to put it in the driveway, she wouldn't fire. A few hours later, she fired right up and ran fine. Now it won't fire again. I checked to see if the coil was sparking and it wasn't. So, I tried another coil that did work and it didn't spark either. Could my TFI be going out on this truck? Would a bad TFI keep the coil from sparking? Thanks.

 

[jrichker]

No working TFI = no spark, no matter how hard you try.

My TFI recently died in a similar manner. The engine fired up and promptly died. It refused to start from that point on until I replaced the TFI.

 

[88 Fox GT]

I think it's probably the TFI, but the parts house said they can test mine for me and a new one is like $30. So, I will probably go and have it tested tomorrow. I imagine I will probably end up buying a new one cause I know it's fairly common for these to go out and this one has 170k miles on it. Thanks.

 

[z9_87]

170k, yeah replace it. These things suck, they can go out while you're driving down the road... at 70mph, just die.

 

[tripwhite93]

Check out this web site. http://www.dccurrent.com/fbt/tps.htm

 

[z9_87]

Check out this web site. http://www.dccurrent.com/fbt/tps.htm

TFI, the thing on the side of the distributor, not the TPS.

 

[bcd]

they can test a tfi at advanced auto parts

 

[gork1rogues]

My F150 would do the same thing. Start up fine then run for a while, shut off, no start up, wait a while, would start up, then it finally wouldn't start anymore. Replaced the TFI and all is well.

 

[tripwhite93]

TFI, the thing on the side of the distributor, not the TPS.

OOPS your right

 

[RsStanG1987]

My friends car needed one the car would start and run fine, But once it warmed up it would cut out. He replaced and the problem went away.