Weird one...

[santafepilot]

Hi guys,
First off this site is great! Have used it many times as the go to guide.

Had a strange one happen today on a 86 ranger 2.9 4X4, was driving along just fine after several stop and starts and the engine just quit. No noises/surging etc, just dead. Pulled over (deserted road and a convenient pull off just ahead thankfully) popped the hood and looked around and found the TPS sensor unplugged. Very strange, connection is solid. Put it back on and went to fire her up and cranks but won't fire. Tried switching tanks in case of fuel pump, same thing.

After a tow home, dived into it some more and there's no spark. Is a relatively new Motorcraft distributor though the ignition coil is pretty old. So the question is, without a TPS sensor the truck won't even drive right? If the TPS fell off while driving would it have overloaded the ICM? What should I be looking at??

Use the truck for work and need her back up ASAP! Please HELP!!!

Thanks so much!!!!

 

[adsm08]

I would chuck a TFI at it before going any farther.

 

[RonD]

The MAP sensor could be used alone if TPS failed or wasn't working, but you would notice a lag in throttle response.

Yes, no spark = TFI problem, they have a 100% failure rate
Good point by point diagnostic here:
http://www.therangerstation.com/tech_library/TFI_Diagnostic.html

Print the worksheet and follow the steps

 

[santafepilot]

Thanks!

TFI and ICM are the same thing right? Looks like a pain to get to, is it humanly possible to get it off without pulling the distributor? Read it's a 5.5mm socket, but they sure feel like allens...

 

[santafepilot]

Thanks again!

Thanks for the links RonD. Guess that special tool it is the trick! Will get them both tonight hopefully.

 

[santafepilot]

Thanks again and wish me luck!

Am waiting on my girl to get back so I can go get the parts, thankfully in stock for $40 with lifetime warranty. For that price and my time-frame, I'll skip the tests. Just wanted to say thanks so much again for your quick help! Been lurking this site for awhile (years) and will try to contribute more, though my expertise is mainly with bikes, some of it translates. Not quite as many bits though.

This truck has always felt sluggish, but I drive her like a grandma (never really above 3.5rpm) and am used to 150+HP bikes, so most cars feel slow...

Have read a lot of the tech articles and replaced almost all the sensors when I got the truck along with a bunch of other work, but somehow I missed this one. Love this truck, parts are cheap and mainly easy to work on!

 

[santafepilot]

Nailed it!

Thanks guys, got her going this morning as no light outside and the garage is for bikes, was surprisingly easy with that tool. Just dipped my hands in ice to make them smaller...

Runs way better with the TPS connected...

On a bike if that disconnects you're basically dead... I reset/calibrate/test them every year.

Thanks again!!

 

[RonD]

Good work

 

[billpac4u]

Way to go, SFP!

I love happy endings!