ides ok but back fires and tries to stall when accelerating

[kolaughlin]

i have codes p1506 p 0402 p 0172 p 017 its a 97 ranger 2wd vin x

 

[RonD]

Did you look up the codes?

There is no p017
I will assume p0171, and with p0172 these mean one bank of the V6 was running too lean and too rich at some point.
So most likely symptom not the problem, but O2 sensor on that side could be suspect.

p1506 points at the IAC, idle air control
This is a valve on the intake that opens and closes to let more or less air into the system, it is operated by the engine computer(PCM or ECM) based on the readings from other sensors.
These can be tested and cleaned.

p0402 points at the EGR, exhaust gas recirculation, this is also a valve that opens and closes to let exhaust gas into the intake to reduce pollution.
These can be tested and cleaned.

None of this means the IAC or EGR is at fault, it could be something as simple as a cracked or unplugged vacuum line somewhere, allowing too much unregulated air into the system and the sensors are trying to compensate for it.
A clogged PCV could even be the problem, easy to clean and test.

One thing to remember about sensors and the ECM(engine computer), the ECM has a memory and simply swapping out sensors often doesn't work because of the ECMs memory.
If you do work on a sensor, i.e. clean it or replace it, disconnect the negative battery terminal for 10 minutes, like while you are working on the sensor.
When you connect the ECM back to power it will reconnect to all the sensors and relearn their engine off settings, so the cleaned or new sensor's settings are being used not the old settings.

 

[kolaughlin]

ive checked for vac leaks. only place i could find a leak was where the egr tube goes into upper intake. the rubber bushing wasnt sealing. i cant find the part anywhere, i tryed rtv but maybe still leaking.

 

[97RangerXLT]

Clean the IAC. On the 97s, there is an issue with a gasket failing between ports in the fuel rail to lower intake. you cannot see this because it is completely internal, and you have to take the upper intake and fuel rail off to see it or fix it. But it is common enough that Ford issued a TSB on it. so if you are confident that there are no external vacuum leaks, I would look at this. And even if you are confident there are no leaks, I would grab a can of carb cleaner and spray it around the intake at different areas while the engine is running. if the engine revs up a bit, you have a leak...

And after it is all said and done and you have exhausted the easy fixes, take a look at the fuel rail to lower intake gasket... Here is a glimpse of what you are getting into:

http://www.therangerstation.com/forums/showthread.php?t=94437

you don't have to remove the valve covers, but it might make it easier to work on the intake if you take the lower intake out, in which you will need to remove the valve covers as they seat against the intake as well as the heads.

AJ

 

[kolaughlin]

i think ive fixed it. the rubber gasket/ o ring that is on the egr tube where it enters upper intake was not seated properly. just got it to seat this morning. so far no cel and no sputtering on acceleration. im going to drive it around a bit to see.

 

[RonD]

Good work

 

[97RangerXLT]

Sweet! Thanks for posting back with your solution. This could help someone else down the road.

AJ

Sent from my DROIDX using Tapatalk 2

 

[kolaughlin]

that tube was a pita to get back into upper intake.