Long time listener First time caller

[Chiis97XLT]

been recieving advice on here for years I have owned several explorers. This one I have now Is throwing me an assortment of issues from misfire codes on cylinder5,6 to lean codes on each bank it has new injectors upper intake gaskets plugs wires fuel pressure regulator fuel pump fuel filter. Ive looked around for vacume leaks I know I have a charcoal line suction valve on top of the tank that needs to be replaced at the 90 degree connection on the top of the tank. It broke as i was replacing the fuel pump. I hadnt thought it would cause many issues. What are thoughts on if this is causing my inconsistent Idle and sometimes even for it to stall at a stop sign. took the camshaft position sensor off and cleaned it. Im kinda at a end rode to thinking maybe it jumped timing it has 240k on the engine 4.0 0hv automatic 4x4 bc it is using excessive amounts of fuel and dosnt have power to get out of its own way most days. the Idle will fluctuate from 1200 to as low as 300 or stall. It seems like it will idle fine and like a relay kicking off the rpm gauge drops.

 

[Rick]

Plug the vacuum line so it isn't sucking air and see if that helps until you can replace the connector.

 

[Chiis97XLT]

Yea I am going to get out to do that this afternoon or in the morning and see if it helped and Ill let you know

 

[410Fortune]

Check fuel pressure
How are plugs and wires? Coil pack any cracks on the bottom of it?

How quickly do the misfire codes appear? Meaning if you clear them then go drive so they show up immediately or does it take some driving?

Not often does a ohv jump time

Check firing order
1 2 3 passenger side
4 6 5 drivers

If fuel pressure checks out 64 psi
Firing order is good and plugs wires are good
Listen to injectors click while running
Check all wiring and connections
Then it would be time for a compression test
You may have lost some valve seals or? Compression test will show any issues with the head or gaskets

 

[Chiis97XLT]

I'm going to check the fuel pressure and vacuum pressure today The plugs and wires are new i went through two sets just trying to be sure I didn't get a bad set. but I pulled 456 and 4 looked fine 5 was pretty wet and gooey it had the stem covered in some sludge. The codes don't come back immediately and I can sit in it running diagnostics and hear it missing like hell but it doesn't hit the check engine light. it could be burned out by now though bc it wasn't on when i pulled those codes yesterday.

Ill check the pressures and get the vacuum lines sorted. Its amazing how horrible it runs I tried to load a video of it to the forum yesterday but it said it was too large of a file. to show the rpm gauge fluctuating and its backfired so much by now that im thinking the manifold gaskets are bad bc the bolts are tight. but still chugging like a locomotive. but the engine doesn't smoke unless its cold ill see a blue puff but its nothing major. its never ran hot to be cracking heads like I'm reading in other forums but the issue definitely has my head going in circles.

 

[410Fortune]

I see it’s a 97 sorry fuel pressure should be 42 psi +\- with two fuel lines (return style fuel)

Check engine light is important
It should come on with the key in run and go off when cranking starter.. this indicates pcm getting signal from crank sensor

The cam synchronizer looked okay when you had the sensor off?


Let’s start w the basics
Fuel psi
Firing order
Didn’t leave tape over intake ports when intake was off lol lol lol (been there done that)
Clean mas air flow sensor
Plug gross vacuum leak
Listen to injectors click while running ( can feel them)
Check all your work and wiring
Listen to exhaust flow, can probably hear the missing, want to make sure cat converter is not plugged up (would start glowing red in the dark after running for a hot, exhaust sound muffled)
Can watch the engine run in the dark see if any blue arcing between plug wires and block
No mice nest in intake

Over the years I’ve seen it all
Then compression test

I assume all the parts you have thrown at this are because of the missing
The missing is not something that happened after the parts
If yes This points to compression/ head issue
Over 200k the ohv can start to have head gasket / head issues and eventually the valve seats basically fall out and you get very low to zero compression

 

[Josh P]

Pretty serious ignition issue that I don't have an answer to. Cylinder 5 spark plug being wet is probably the cause of the backfire.

 

[Chiis97XLT]

Ok so I went through the plugs and wires number 5 was wet 6 showed signs of rich environment. Had a bad TPS and firmware updated my other scanner to read live data. Im seeing a lean reading on bank 1 and a very rich environment on bank two Im not sure why that would be happening and the truck is idling at 1000 rpm Ill clean the Iac or replace it and ran vacume tests. everything seems to be fine there. The tps sensor definitly helped bc it was only showing 8% open all the time. so that was a big issue. Any help is appreciated on the lean and rich situation. All the injectors are new Im wondering if i have a collapsed or clogged return line. not sure.

 

[Chiis97XLT]

these values were only after 5 min of running after replacing the tps and clearing the codes. so it may be needed to drive until the computer loops and then see if it is finding its way but the the calculated load seems high at 39% to be in bark and 1800 rpm

 

[Chiis97XLT]

Ok after driving it around all the values seem to be comming around and are getting alot closer I also forgot to mention I changed the coilpack the same time i changed the tps. it idles at the correct trim and the ltft and stft are looking good. It just needed to get a couple miles on it after the parts were changed and the ECM codes reset.

 

[410Fortune]

If it is having a problem with a. Injector it will cause some crazy readings side to side

Remember you only get a lean code after it has detected the lean conditions, attempted to compensate by dumping fuel and then when it’s not able to correct the lean problem you get a code

I have had brand new out of the box injectors bad.. I recently had one stuck wide open and every time o turned the key and primed the pump it was just dumping fuel into the crank case