Hey guys I'm new to the bronco world. I just purchased a 1990 bronco with the 5.8. Upon purchasing from a family friend he said it stalls out at a light sometimes. I bought and drove home about 5 miles and stalled at a light. It fired right back up and got me home. I then cleaned the k&n airfilter and also did a good cleaning on the throttle body spacers which seemed to be pretty dirty. I drove it Sunday and it worked perfect all day not even a sputter when it was 105 out. Me being very excited hoped in it Monday 105 again drove about a quarter mile and went a a pretty steep inclines street and it cut out about halfway up. And wouldn't start again. Went back several hours later it fired up but when I tried to go it was not running good. Made it to the top of hill it started running great. Any ideas would be greatly appreciated. Guy said he recently changed fuel pump and the throttle position sensor. Thanks guys.

 

couple things, get a stock airbox assembly back on there and get rid of the K&N setup. Also remove the throttle body spacer, these are paperweights.

This could be several things. TFI module on the Dizzy being faulty, these act up when they overheat. I would get a fuel pressure gauge and test key on engine off, start up the truck and see what the pressure is. You should see 39psi running and driving.

check for vacuum leaks as well. check the timing with spout connector removed. should be 10* btdc

 

+1 to what Kemicalburns mentioned. The next time itt stalls shoot it with some starter fluid and if it does nothing the 30 buck TFI module would be at the top of the suspect list for causing this problem.

I like to test before replacing a part. The problem with testing a TFI module is they can test fine when cold and only fail at high temp.

The TFI is about 30 bucks & the tool to remove the recessed screws is about 10 bucks.
If you do replace it remove the screws and pull down on the TFI

 

I just replaced the fuel filter on the bronco. I used my code reader and I am pulling code 23 throttle sensor out of range. I was told by previous owner they just replaced the sensor. Any ideas. Thanks. And the tfi was replaced. Found the old one in a box in bronco.

 

Measure the TPS output to see if it truly is out of specification.

 

it probably is. we have seen plenty of out of the box TPS fail. look at getting a motorcraft tps from rock auto or ford

 

Figured it out finally guys. Forgot to write about it. Narrowed it down to the power wire to the fuel pump relay was not making a good connection. It would rattle loose and cause for the sputtering and stalling. Did a temporary fix to make sure that was it until buying new harness. So far so good.