Any thoughts on these symptoms/engine codes

[jxtlbtironman]

2007 Ford Explorer XLT Ironman, V6 4.0

Out of nowhere it began to misfire while driving down the road today. Ended up at the garage with the following trouble codes:

P0109 Barometric sensor circuit intermittent
P0121 Throttle Position sensor range
P0300 Random Misfire
P0302 Cylinder 2 misfire
P0316 Misfire occurred within 1st 1000 rpm
P2135 Electric throttle control throttle position sensor A/B voltage correlation

The garage told me they could not figure out what the problem is and that the guy who needed to take a look at it wouldn't be in until Monday. It was only about 2 hours before close on a holiday weekend so it's likely the mechanics had BBQ plans and didn't want to hang around extra time to do the work, understandably.

Anyone think this is a fairly easy fix? Throw on a new TPS and call it a day?
Other recommendations? Waiting until Monday isn't exactly an option for me at this point.

 

[jcevans2]

I would start with checking all the spark plugs to make sure they are not fouled up, corroded, or damaged. Make sure they are properly gapped. Personally, I like to use spark plugs that don't require gapping. They are more expensive but faster to install - literally plug and play.

Also make sure the spark plug wires are routed correctly. Check it against the routing diagram in the owner or repair manual. if a spark plug is bad, swap it into a different cylinder and check to see if the trouble code moves to the new cylinder.

That's all I have to offer. I hope someone with more knowledge comes along soon to help.

 

[jxtlbtironman]

Thanks for the reply. I think all of that should be ok - all new plugs and wires put on last year, sometime around September if I remember correctly - all connections seem tight. The one code also indicated random misfires from different cylinders, so that leads me to believe it's a broader issue than perhaps a bad plug in one cylinder. Perhaps it's not getting the correct air/fuel ratio to fire correctly. Maybe a bad sensor causing the computer to miscalculate what it needs at any given moment, or maybe even a bad distributor? I just do not know enough about the throttle sensors to know if that is the source of the problem.

 

[swshawaii]

Sounds like a similar TPS or throttle body issue. GL

http://www.explorerforum.com/forums/showthread.php?t=273461&highlight=tps

 

[jxtlbtironman]

Information update:

Replaced throttle position sensor with no luck in correcting issue. The garage looked at it today and initially came back saying it needed all new plugs and wires and possibly a coil. I could have bought into the coil being bad, but the plugs and wires seemed absurd to me; they were replaced at the end of last summer and only have 20-30k miles on them. They did some more work without replacing the plugs - I'm not sure what all it is they did at that point, but a few hours later they told me they still can't quite figure out what is going on. They reset the codes and subsequently they all came back when they rescanned it. Their recommendation is to get it to a Ford dealer for further diagnostics. The garage that it is currently at is very capable and I've never had anything go wrong that they couldn't fix so I'm starting to wonder just how bad of a problem I really have. I spoke with the nearest Ford dealer and they can't take a look at it until at least Friday!

Given that info. anyone else have any further thoughts on the malfunction?

 

[Tech By Trade]

plugged up fuel filter starving no2 on the rail? Champion spark plugs?

 

[jxtlbtironman]

NGK iridium plugs. I've wondered about the fuel filter myself, but it seems like that is something the garage would have easily determined and resolved.

 

[Tech By Trade]

You might think that, but one feller had his front diffy replaced at a great shop, and then the Ujoint I told him about shortly after. Probably the most expensive Ujoint replacement in history.... but I bet it was the front diffy

 

[jcevans2]

I had a whole bunch of engine codes once after some major work. I had them checked and was told things like "it's your oxy sensor, it's your fuel filter, maybe a bad fuel injector". None of the above. The people that did the engine work did not reconnect the PCM computer's ground wire to the firewall. I know my engine well enough to have noticed it was not connected to where it was supposed to be. I had to hunt down a replacement stud with hex nut welded to the middle of it so I could reconnect the wire. The majority of the codes went away.

Maybe you have a broken or disconnected wire at a point just beyond where the circuits of multiple systems come together.

 

[jxtlbtironman]

turns out to be a valve spring. see attached picture. They are going to replace all of the springs, head gaskets, bolts, and timing chain guides. Also have a small leak in radiator - so changing that and the thermostat. Pulling the engine to do all of the work. Anyone recommend any other work while the motor is out?

Or, well, scratch that posting a photo. Can't figure it out if I can. Insert photo opens a box with http:// and I can't find a spot to upload from my computer. Just picture it mentally I suppose.

 

[jcevans2]

turns out to be a valve spring. see attached picture. They are going to replace all of the springs, head gaskets, bolts, and timing chain guides. Also have a small leak in radiator - so changing that and the thermostat. Pulling the engine to do all of the work. Anyone recommend any other work while the motor is out?

Or, well, scratch that posting a photo. Can't figure it out if I can. Insert photo opens a box with http:// and I can't find a spot to upload from my computer. Just picture it mentally I suppose.

Try Photobucket. Registration is free. Make sure your image is an appropriate size and has an appropriate filename. Upload the image to your library. Go to your library and point to the image and popup menu for that image. Click on "Get Links". A box will appear with links for posting that image in various types of communication. For a forum post, click on the IMG code (the one that starts with [URL=http://). The link is automatically copied to the clipboard so it can be pasted directly in your forum message.

It is helpful to use multiple browser tabs or multiple windows so you can be logged into both sites at the same time. Paste the IMG code link directly in your forum message on a line or paragraph by itself so it won't get mixed up in the text of your message.

If the image displays too large, use a program to reduce the size of the original (or copy of the original), upload the new image, and edit your message post with the new IMG code link.