bronco keeps dying while driving.

[jeremyposey]

Ok, a little about myself, I used to be a mechanic in the us army, I have short trem memory loss and slight brain damage now.

So I need some help.

I have a 1991 ford bronco xlt with a 5.8l.

this vehicle sat for 6 years at my dads house, untill 3 weeks ago.

I have changed my fuel pump, fuel filter, blew out fuel lines. changed both green and brown relays. changed coil, Grey TFI on side of dizzy, changed pip inside of distributor.

1. Past issues. 2 weeks ago I was driving and the engine lost power, started pinging and backfiring. then it would die. after about

40 mins it would fire right up. and then 10 20 mins later would do the same thing SO I CHANGED MY TFI. the problem was still the same,

would run great cold, and then would die when warm. but now it would fire right back up, instead of waiting 40 mins.

SO then I CHANGED MY GREEN RELAY AND BROWN RELAY. CHANGED MY COIL AND PIP INSIDE OF DIZZY.

NOW it starts rights up, will run but is constantly dying. will pull off the road wait 5 mins. and then I am good for another 10-20

minutes of driving before it dies agian.

WHAT AM I MISSING? I have spent all 4th of july weekend cleaning grounds and checking connections. all seems ok.

Here are some questions I have.

1.WHAT IS THE GREY RELAY? UNDER THE HOOD NEXT TO THE GREEN AND BROWN ONE. DOESNT SEEM TO MAKE A DIFFERENCE IF I REMOVE IT OR NOT.

2. COULD A FAULTY TPS SENSOR CAUSE THESE PROBLEMS. I HAVE DRIVEN WITH IT DISCONNECTED. STILL DIED. JUST SHIFTED HARSH.

3. COULD THE COOLANT TEMP SENSOR CAUSE THIS PROBLEM?

4. I am suspect of my starter relay, silinoid on the passenger firewall next to the vaccum canisters.

Please Please point me in the right direction.

Because of my short term memory loss I have a really hard time working out of a repair book now. I cant remember the steps or where

I am at in the diagnosis process.

Thank you for your help.

 

[miesk5]

yo jeremyposey,

Welcome!

And most importanty, appreciate your sevice and sacrifice soldier!

re; WHAT IS THE GREY RELAY? UNDER THE HOOD NEXT TO THE GREEN AND BROWN ONE. DOESNT SEEM TO MAKE A DIFFERENCE IF I REMOVE IT OR NOT.

I have no info on the Grey Relay, but others may have the answer fr you soon.

EEC Relay is the BROWN Connector

it is next to GREEN Fuel Pump Relay Connector

Under hood behind air cleaner assy)

Location pic in a 90 and all up to 91

http://img130.imageshack.us/img130/9307/temp90pics033ru4.jpg

Source: by Need4racin (The 90 Bronco, Dean)

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EEC Relay Location in a 90 Diagram; on driver's side fender apron

Source: by Seattle FSB (SeattleFSB) at SuperMotors.net

Fuel Pump Relay Socket Corrosion Info; "...if you had corrosion in your relay socket, then you probably have it other places. one at a time unplug all relays and connectors on that fender and spray them down with contact cleaner. then after you let that do it's job for about 30min-1hr, go back and unplug each relay and connector again (one at a time) this time put them together with di-electric grease. you can buy a tube of it from any electrical/electronics supply or auto store. make sure you get everything plugged back in..."

Source: by datrimm

Next is to Check for Diagnostic Trouble Codes (DTC)s

I alsways need my better-half tohelp on this;

Try a Self Test by my pal, BroncoJoe19

do the KOEO = Key On Engine Off portion first

& Remember to have engine @ Normal Operating Temperature before doing the KEY ON ENGINE RUNNING (KOER) portion

And Post em here according to

KOEO

& KOER

I suspect any NON- FORD MOTORCRAFT PIP or Ignition Module.

Be well, hang in there and the DTCs will help lead us all to a bad PIP part or other part, but don't buy any now.

 

[Rons beast]

Just a thought....Pinging and backfiring indicate a possible lean fuel mixture. Since this happens after the engine get warmed up, I would look for a vacuum leak from a line or device that gets vacuum at full engine temperature. After the engine cools the temperature controled vacuum source would close and the lean condition would not exist. There should be a code or codes stored to help diagnose this as Miesk said.

Thanks for your service.

Good Luck and let us know what you find.

 

[Seabronc]

The pinging could be a timing problem. It could also be caused by the EGR not opening when it is supposed to. Have you checked the basic timing which is set with the SPOUT connector removed. I believe your truck should be set at 10 BTDC with it removed. Check on the emissions sticker under the hood to make certain.

Good luck,