1999 Ranger 3.0 Rough Idle and Shakes violently under load.

[Svtkidd23]

Truck is a 1999 ranger 3.0 4x4 with manual trans.

It was driving perfectly fine and started idling terrible. Its done this before I changed plugs wires and it was fine.

This time I was in traffic truck has been fine for 5k miles. Waiting in traffic stop and go stop and go it had same idle...

Dug deeper into the truck found a tornado in the intake LOL. pulled that out cleaned MAF and IAC. Had 2 codes on my scanner P0171 Bank 1 too lean
and P0302 Cylinder #2 misfire.

Changed plug again on #2. Checked and verifyed spark on #2 cylinder. Still running rough as can be. I checked the injector and it had .29 ohms so i replaced that. Lean code went away. Still missing. yet no code.


I found a hole intake and plugged it with a bolt it came from oil filler cap vent to the intake. Something somewhere has a vac leak I think... We have spark and fuel. Unless the compression is bad.

Pulled plug and started it and it sounded like it had a lot of compression, wont know till tomorrow.

sprayed carb cleaner all around the motor and nothing changed rev wise.. so I dunno on vac leak

Cliffs:
Truck idles terrible and shakes truck violently until 2800 ish up
Coil is good
New plugs, wires, injector
po171 and po0302
plugged intake from oil filler cap
carb cleaner caused no change in idle around hoses
new dpfe sensor
No power... driving me bat shit crazy

 

[oldmodman]

I have a 92 Explorer with nearly identical idle problems.

It was a bad connector from the coil drivers to the coil. I found a good wiring harness sub assembly and a nice clean coil pack at "Pick Your Part" and installed them.

All problems gone. Total cost - $3.00

 

[Svtkidd23]

I have a 92 Explorer with nearly identical idle problems.

It was a bad connector from the coil drivers to the coil. I found a good wiring harness sub assembly and a nice clean coil pack at "Pick Your Part" and installed them.

All problems gone. Total cost - $3.00

Im thinking this is valve related. The heads on these are junk supposedly. But it ran fine yesterday...

 

[kevinatfms]

IIRC the cylinder heads were known for valve spring issues. They were the weak single coil springs while the later 3.0's had the secondary coil added to the spring. Does it constantly misfire or does it clear up once in a while?

Also, when was the last time the DPFE replaced and is it a metal housing or plastic? Those were notorious for causing all kinds of weird idle/drive-ability issues.

One last thing could be the PCV hose under the intake. Those were known to crack and break off.

 

[silver03svt]

Sounds like a coil pack misfire. Wife's explorer (4.6 V8) did the same recently. It is far more noticeable when the engine is under load.

 

[03cobra#694]

Not a Ranger, but my wives 04 Escape (3L) shit a coil and did the same. Took forever to throw a CEL to see which one needed to be replaced.

 

[SID297]

It definitely sounds like an ignition issue.

 

[Svtkidd23]

IIRC the cylinder heads were known for valve spring issues. They were the weak single coil springs while the later 3.0's had the secondary coil added to the spring. Does it constantly misfire or does it clear up once in a while?

Also, when was the last time the DPFE replaced and is it a metal housing or plastic? Those were notorious for causing all kinds of weird idle/drive-ability issues.

One last thing could be the PCV hose under the intake. Those were known to crack and break off.

idle to 3000 rpm then clears up with lack of power

Sounds like a coil pack misfire. Wife's explorer (4.6 V8) did the same recently. It is far more noticeable when the engine is under load.

Coil pack checks out fine. Also doing the test with plug out the head and a negative cable to battery and plug its showing plenty of spark

Not a Ranger, but my wives 04 Escape (3L) shit a coil and did the same. Took forever to throw a CEL to see which one needed to be replaced.

Im pretty sure it checked fine on my multi meter will double check in few hours

It definitely sounds like an ignition issue.

I agree or a bf vac leak.

I'll post a video lol

 

[Svtkidd23]

fixed links

 

[Svtkidd23]

[video=youtube;SPj9vnnFIKo]https://www.youtube.com/watch?v=SPj9vnnFIKo&feature=youtu.be[/video][video=youtube;jW65mx2qc94]https://www.youtube.com/watch?v=jW65mx2qc94&feature=youtu.be[/video]

 

[bdcardinal]

There is a TSB for ~05 Rangers 05-26-03 to replace the heads. Similar symptoms as you are describing.

 

[Svtkidd23]

There is a TSB for ~05 Rangers 05-26-03 to replace the heads. Similar symptoms as you are describing.

Checked compression and it's ok...

180-180-172-175-178-168

I think coil is bad, low voltage end is fine. I think the tower isn't

 

[Svtkidd23]

Replaced coil same thing

 

[kevinatfms]

I read above again and you said that you found a hose coming from the oil cap that you plugged with a bolt? Where did the other end of the hose go? I am assuming now that you have a vacuum leak somewhere.

 

[Svtkidd23]

I read above again and you said that you found a hose coming from the oil cap that you plugged with a bolt? Where did the other end of the hose go? I am assuming now that you have a vacuum leak somewhere.

Just went to intake checked with carb spray no leak


It is a oil vapor vent that reburns any mist with vac from motor

It plugged won't do anything

 

[Svtkidd23]

will a cam sensor cause a mis?

 

[mrlrd1]

will a cam sensor cause a mis?

No. A failed camshaft position sensor or an out of phase sensor (incorrect camshaft synchronizer installation) will cause a phantom misfire - it will set misfire DTCs WITH NO ACTUAL MISFIRE.

Either perform a power balance test manually or find a scanner capable of performing one. Another option would a scanner capable of Mode 6. Either way you need to verify that cylinder 2, and only cylinder 2 is actually missing. Don't go any further until you do.

Have you checked fuel pressure? I've replaced dozens of pumps on those trucks for your EXACT symptoms.

 

[Svtkidd23]

No. A failed camshaft position sensor or an out of phase sensor (incorrect camshaft synchronizer installation) will cause a phantom misfire - it will set misfire DTCs WITH NO ACTUAL MISFIRE.

Either perform a power balance test manually or find a scanner capable of performing one. Another option would a scanner capable of Mode 6. Either way you need to verify that cylinder 2, and only cylinder 2 is actually missing. Don't go any further until you do.

Have you checked fuel pressure? I've replaced dozens of pumps on those trucks for your EXACT symptoms.

Found out the new injector I got was for the non flex fuel therefore has a different hat with .2 ohms more giving it. A closed command.

Swapped injectors and fired of course gave it a dead cylinder where new injector is

Ordered oem replacement xl5 a2a
Not a b2b

 

[Sirraf]

I had this same issue and it was the ignition control module. Ran like a dream after replacement.