Truck cranks but won’t start!

[87Danger_Ranger]

1987 2.9L Manual. So I was on my way home today, when the truck just died out on me. Has been running just fine. Had a half tank of gas so I know having fuel isn’t the issue. Coming down the street and just lost power. Was able to turn onto a side street and get up to the curb. Tried starting her back up but nothing. Cranks and sounds like she wants to start but just won’t. Got her towed home and got dark on me so will be working on her tomorrow. My guess is the fuel pump, but I know these trucks have two. Any of you had this issue? Any help is appreciated. Thanks in advance guys.

 

[cobrajocky]

I've been struggling with POSSIBLY the same issue - ran fine, made a few errands, then suddenly won't start the next morning. I got lots a great suggestions for looking at everything from Fuel Injectors, tecting fule pressure at "the rail" to bad Coil, to the dreaded pull the truck bed to replace the Fuel Pump. No one suggested tracing out the electrical from the Fuel Pump Relay to the Fuel Pump.

So the next warmer morning I did just that with a 12V probe and found the problem being as simple as the Fuel Pump Entertia Switch which is always in the cab of the Rangers/Mazda B-Series trucks. Mine is on the firewall on the passenger side right at your feet. Now I am not saying this is your issue, but worth checking, it is resistible, UNLESS it has become faulty (mine is). After doing a bit of Google research, I've found that these are an age / mechanical fail limited weak link in the Ranger / B4000 series trucks and the damn things cost $108 retail at Advanced Auto. I'm thinking of just jumpering it out of the circuit. I have a '97 Mazda B4000 4.0L SE model, same as a Ranger XLT.

Read my post for more info and the other advice I got.

Oh Brother - suddenly B4000/V6 won't fire up after running the day before!

First find out if it is fuel or spark related. What superunknown98 said is the best way, you can use starting fluid or throttle body cleaner directly in intake if it cranks it is fuel if not more than likely spark. Just don't get crazy and spray to much about a 1 sec burst into the front of the...

www.therangerstation.com

 

[RonD]

1987 2.9L Manual. So I was on my way home today, when the truck just died out on me. Has been running just fine. Had a half tank of gas so I know having fuel isn’t the issue. Coming down the street and just lost power. Was able to turn onto a side street and get up to the curb. Tried starting her back up but nothing. Cranks and sounds like she wants to start but just won’t. Got her towed home and got dark on me so will be working on her tomorrow. My guess is the fuel pump, but I know these trucks have two. Any of you had this issue? Any help is appreciated. Thanks in advance guys.

Do 50/50 test, spray fuel into the intake and try to start engine
If its starts and then dies spark is OK, fuel delivery is the issue
If it doesn't start then spark is the problem
50/50 instant results

If it starts and dies then its a fuel delivery issue, turn key on and off and listen for the fuel pump to run for 2 seconds each time key is turned on
Fuel pump is not quiet, you can hear it run in the cab, a HUMMMM for 2 seconds just after key is turned on
Yes there are two fuel pumps on a 1987 Ranger so can be tough to hear if both are working

If it doesn't start with added fuel then its a spark issue
If you have a CEL(check engine light) in a 1987 it should come on with key on
CEL should go OFF while starter motor is active IF computer is getting a timing pulse from the TFI module(spark module)

 

[87Danger_Ranger]

Thanks for the responses guys. So I got in the truck and found the inertia switch and reset it. As was said, it should have resistance which it did. I held it for a good bit, turned the key over, let it go and the truck fired right up. Ran for a bit parked it and let it be. Later in the evening, it didn’t not want to start yet again. So I did the same thing with the switch and started right up again. My guess is the switch is bad. You guys know how I can bypass this switch and just connect it to a rocker or toggle switch. I want to go that route.

 

[sgtsandman]

The switch is there to kill the pump if the vehicle in an accident. If it’s bypassed, you have the potential of the gas tank getting emptied all over the scene of the crash and create a big fire hazard because the pump will keep running until the ignition is shut off. Better to replace it than by pass it.