Help!!!!

[Rusty Shackleford Gribble]

Hi all and thank you in advance for any advice!! So I have a 91 ranger 2.9. I was driving one day and it started running really rough. I made it home and then it wouldn’t start. It took me FOREVER to figure out that it was the ecu that went bad. Bought one from rock auto and fired right up. A couple weeks later it died again. Same exact symptoms. The ecu was under warranty so I ordered a replacement. Fired right up again. Well…it just died again. Same symptoms. I’m pretty sure I know what the culprit is. My question is, are any of you aware if there’s something else faulty the system that could be frying these units? Or is it possible these remans are just garbage? Oh, and when I swapped it the first time, the ecu that was in the truck when I bought it was a reman from 2015 so someone had already replaced it before. Thanks!

 

[SenorNoob]

Sounds like you have some bad wiring somewhere to kill computers that fast.

 

[Curious Hound]

Whats your system voltage?

 

[Rusty Shackleford Gribble]

Whats your system voltage?

Pardon my ignorance but what voltage am I checking and where? Thank you

 

[Uncle Gump]

Pardon my ignorance but what voltage am I checking and where? Thank you

He means system voltage... more precisely running system voltage. Across battery terminals is system voltage.

That ECM should be protected for system voltage at 16 volts and above.

 

[Rusty Shackleford Gribble]

He means system voltage... more precisely running system voltage. Across battery terminals is system voltage.

That ECM should be protected for system voltage at 16 volts and above.

Thank you. Sorry but I’ve never checked that before and wouldn’t know where to start. Any advice? I’ll try looking on the web

 

[Uncle Gump]

Here is the best picture I have...

It just pulls straight out.

 

[Rusty Shackleford Gribble]

Sorry. I’m confused. Is that a fuel pump/sending unit? Are you saying I need to check voltage there?

 

[Uncle Gump]

Oh my bad...

I posted that in the wrong thread. It

 

[pentode]

Thank you. Sorry but I’ve never checked that before and wouldn’t know where to start. Any advice? I’ll try looking on the web

All you need to test your voltage is a multimeter. Set the meter to DC volts and touch the black lead of the meter to the black (-) terminal on the battery and the red lead on the red +

 

[Rusty Shackleford Gribble]

It reads 14.34 volts at the battery

 

[Uncle Gump]

That shouldn't cause a problem.

 

[Rusty Shackleford Gribble]

That shouldn't cause a problem.

Yes sir. Really scratching my head. So I went to a scrap yard and got 2 ecus. It’s running again and I guess I’ll see if this one lasts. Up until now it’s only had remanufactured ones in it since I got the truck. Hoping maybe when they “reman” them they maybe use cheap components? Cracked this one open and all it looks like they did was change two capacitors.

 

[Terrys87]

Clean your grounds real well. On post 39 on my build, I show several of the locations of the grounds.

My 87 Ranger I will be restoring soon I want to keep track of my progress and add information as I find it.

www.therangerstation.com

 

[SenorNoob]

That probably is all they did. Most of the rest of the parts in there are probably unobtainium now.