1997 Ford explorer bucking and jumping when accelerating

[billwilliams]

Yes I have a 1997 Ford ranger XLT 2 wheel drive on acceleration at bucks and jumps and will not accelerate more than 20 miles an hour I've changed all the sensors I've done EGR valve I've done the coils the coil packs the plugs plug wires and still just jumps and bucks when I accelerate on it anybody has any ideas

 

[franklin2]

Check your fuel pressure while driving.

 

[billwilliams]

Check your fuel pressure while driving.

Checked while parked but can't get it to high rpm to drive it thank you

 

[scotts90ranger]

Parts cannon method is hard to diagnose, anymore new parts doesn't mean good parts...

I would look pretty good for vacuum leaks too, MAF systems really care about that. Also, the main fuel pressure that matters can be read with the engine off, just key on and let the pump cycle and it should go to the regulator pressure (don't remember what it should be). Also, pull the vacuum hose off the pressure regulator and see if there's fuel there since there shouldn't be any. I would also suggest connecting to the engine with an OBD II reader and watch the fuel trim values as you drive if possible

 

[billwilliams]

Checked while parked but can't get it to high rpm to drive it thank you

Parts cannon method is hard to diagnose, anymore new parts doesn't mean good parts...

I would look pretty good for vacuum leaks too, MAF systems really care about that. Also, the main fuel pressure that matters can be read with the engine off, just key on and let the pump cycle and it should go to the regulator pressure (don't remember what it should be). Also, pull the vacuum hose off the pressure regulator and see if there's fuel there since there shouldn't be any. I would also suggest connecting to the engine with an OBD II reader and watch the fuel trim values as you drive if possible

Thank u very much I think I mite of found problem but can't see it that well here at night and I don't feel like pulling out drop lights I'll check in the morning it seems like the fuel cut off switch that's under the dash is bad and it's cutting it off but I'll find out in the morning thank you for your advice I appreciate everything

 

[RonD]

30-40psi is running fuel pressure in 1997 and earlier Ranger(or Explorer)

+1 on MAF sensor, but CLEAN IT, don't replace it, common cause of bucking in the 4.0l vehicles is dirty MAF sensor
Change fuel filter, every 5 years

Put a vacuum gauge on the intake, start engine, should see 18-21" of vacuum
Raise RPMs a bit and hold it there, if vacuum starts to drop you have a Clogged Exhaust, air(exhaust) can't get out so new air with fuel can't get in, so limited RPM and bucking
Vacuum gauge is maybe $30 and one of the best tools to diagnose a running gasoline engine

Is the CEL(check engine light) on?
You can get a OBDII Bluetooth code reader for $15
It will tell you if a sensor is out of range, not bad just out of range, so NEVER EVER change sensors(except O2s) unless you get a CEL and code, AND you test the sensor first
Just a heads up

My 1994 4.0l has over 400k and all original sensors, except O2s, they wear out after 12 years, only sensors that do
Not lucky just most sensors never wear out
95% of DIY sensor changes were not bad, but the one that gets me the most are 60% of Pro-Mechanic sensor changes were not bad, lol, but they still charge you for the new sensor you didn't need

 

[billwilliams]

30-40psi is running fuel pressure in 1997 and earlier Ranger(or Explorer)

+1 on MAF sensor, but CLEAN IT, don't replace it, common cause of bucking in the 4.0l vehicles is dirty MAF sensor
Change fuel filter, every 5 years

Put a vacuum gauge on the intake, start engine, should see 18-21" of vacuum
Raise RPMs a bit and hold it there, if vacuum starts to drop you have a Clogged Exhaust, air(exhaust) can't get out so new air with fuel can't get in, so limited RPM and bucking
Vacuum gauge is maybe $30 and one of the best tools to diagnose a running gasoline engine

Is the CEL(check engine light) on?
You can get a OBDII Bluetooth code reader for $15
It will tell you if a sensor is out of range, not bad just out of range, so NEVER EVER change sensors(except O2s) unless you get a CEL and code, AND you test the sensor first
Just a heads up

My 1994 4.0l has over 400k and all original sensors, except O2s, they wear out after 12 years, only sensors that do
Not lucky just most sensors never wear out
95% of DIY sensor changes were not bad, but the one that gets me the most are 60% of Pro-Mechanic sensor changes were not bad, lol, but they still charge you for the new sensor you didn't need

I appreciate the heads up you have a great weekend sir

 

[billwilliams]

Parts cannon method is hard to diagnose, anymore new parts doesn't mean good parts...

I would look pretty good for vacuum leaks too, MAF systems really care about that. Also, the main fuel pressure that matters can be read with the engine off, just key on and let the pump cycle and it should go to the regulator pressure (don't remember what it should be). Also, pull the vacuum hose off the pressure regulator and see if there's fuel there since there shouldn't be any. I would also suggest connecting to the engine with an OBD II reader and watch the fuel trim values as you drive if possible

I appreciate the heads up and thank you have a great weekend

 

[JoshT]

I hate to even suggest this, but what does your radiator/coolant look like? Last few times (yes, it was a few times) my truck acted like that was due to failed headgasket. Biggest symptom prior to the bucking/jumping was the dirty coolant. After installing a different engine I haven't had another problem.

Probably not your problem, but if all else fails...

 

[billwilliams]

Thank u about ready to pull motor and get a good look at it

 

[rusty ol ranger]

Whens the last time it had a fuel filter?

 

[2011Supercab]

Always a good idea to post your engine size in each new thread when having engine problems

You have another thread saying you have a 2.3.

Very possible the timing belt has slipped.

 

[rusty ol ranger]

Always a good idea to post your engine size in each new thread when having engine problems

You have another thread saying you have a 2.3.

Very possible the timing belt has slipped.

The title says explorer but the post says ranger....

Im lost.

 

[scotts90ranger]

Probably like me and has multiples... just registered vehicles I have two Rangers and two Explorers... when I ordered hood struts for the Explorers I ordered two sets, the company messaged me making sure I meant to order two sets . That's the assumption I made anyway...

 

[JoshT]

Thank u about ready to pull motor and get a good look at it

Pretty extreme measure for diagnosing and fixing a problem. If you suspect that I could have been right about the gasket, it would be a lot easier to rent a compression tester from the auto parts store. If it is a 2.3 It's probably not difficult to yank the motor, but I would still want to do more diagnosis in the vehicle before pulling it.