The recent drama: head gasket, plugs, dpfe sensor, ignition coil?

[missdawn1012]

Okay so I'm new here but I reference this forum a lot as a guest. Thought I would sign up and ask this particular question. I'm going to be very detailed in hopes that I provide enough information so excuse me if this post is a little lengthy. =) Thank you in advance for anyone who can assist me in the slightest.

Okay, so a month ago, my 1998 ford explorer decided it was going to crank (a strong crank) but not start. This is not a crank like the battery is dying/dead, or anything like that. Well, I thought it was the idle air control module/censor, whatever it's called, because a shop told me some few months ago when I got a tune up that I would need that part. So I bought the part, had my mechanic neighbor put it on for 10 bucks, and that was the end of it. But the car still wouldn't start. So, my mechanic neighbor says he thought it was the PATS system shutting the car done. I brought the car into an American Trans shop where it sat for 5 days.. before they told me it had to be serviced by a Ford Dealer. (Yikes)

So I brought it to the dealer where they told me that spark plug #4 was cracked and I needed a new plug. They also updated by PCM (cost a hefty 312 bucks!), and that was the only problem I had.. They gave it a jump and it started. Somehow though, my headlamps begin to flicker at night now... this problem was new since it was at both shops, prior it had NEVER done that before. They also gave me an oil change because they said there was fuel mixed in with my oil. I asked how that happened and they said, "Probably from continually cranking the engine it flooded itself while someone kept trying to start it."

So a week later, check engine light comes on. Here we go again, only a few days after that, the car is having the same dreaded crank no start condition. I called the dealership, brought it back up there, and this time they told me I needed a DPFE sensor which ran me another 330 dollars this time... They also recommended that I do a full tune up (plugs/wires) and change the ignition coil. Mind you, I just got a tune up over the summer so I asked why I needed another.. They said "Because the plugs are aftermarket." Yeah whatever. I told them to fix the DPFE sensor and let me know how it goes from there. They put the sensor on, car started up fine.. so I paid and took it home.

Only two hours later, the check engine light comes BACK ON. - UGH! - Took it to Autozone, these are the codes that it threw off... P1405 (DPFE sensor upstream hose off or plugged), P0301 (cylinder 1 misfire), P0304 (cylinder 4 misfire), and P0402 (EGR system fault). Kind of friggin frustrating! Considering they just fixed cylinder 4's plug, why the hell would it be misfiring!

So I take it to school that same night, the wheel starts shaking. (drivers front side) another new issue since it was serviced - never did that before! I e-mail the GM of Ford.. expressing my complaints. That same day, my check engine light starts blinking (I couldn't count how many times as I was driving on the freeway, but it wasn't something that repeated itself. I googled and found out that has to do with a major misfiring problem)

I had a friend of a friend who is going to school to be a master mechanic take a peek at it today... He told me that I probably need new head gaskets. He said the cylinder 4 spark plug had oil on it, and the cylinder 1 spark plug had coolant on it.

I guess my question here is, does anyone know about this head gasket issue? I read something about bubbling in the radiator if it does indeed need a head gasket, but I do not ever have smoke coming out of my exhaust. I do not have great pick up, which I guess can be considered a symptom of a blown head gasket. Is a head gasket a part where basically if it's screwed it's screwed? Or are there multiple pieces where only something small can be wrong with it? Not too familiar with this area.

My other question is what would cause the DPFE sensor to throw the code that it's unplugged or clogged? It's a brand new part, I'm just wondering if maybe it was installed wrong, or if the code is just coming up because the part was recently changed.

Is it common for a head gasket to be misdiagnosed two or three times before it's realized that's what the problem is? I guess I'm just really disappointed that ASE certified mechanics did not pick up that the original problems are the head gaskets - if that is indeed the case - but yet a friggin' student could tell that's what it was.

Or do you think the issue is the ignition coil still? Or is that just a wrong diagnosis? And what the heck is an EGR? lol

Thanks in advance for helping & for listening to my little rant/rave. =)

 

[field]

When your engine cranks normally but doesn't start, it means you have flooded the engine. When I accidentally depress the gas pedal before cranking (a big no-no for my SOHC), I must floor the pedal, crank a while to clear the flood, then wait a while. It then starts if done exactly right.

 

[field]

You had a bad beginning in your post. Explorers like mine always flood if the gas pedal is depressed before cranking the engine. You probably only needed to un-flood the engine then. It's late now though.

 

[stickboy]

There are a lot of different places where a head gasket can fail. It is the gasket that sits between the cylinder head and the cylinders, where all the work happens. They have both oil and water passing through them. They also prevent the cylinder's compression from leaking to the outside. That being said, you can have different symptoms depending on where the gasket is leaking. Water can leak into the cylinders (this can cause steam from the tailpipe and bubbling in the coolant, but only if the leak is bad enough). Water can leak into the oil, which as you can guess is all around bad. Water can also leak to the outside of the engine and drip on the ground. The same applies for oil travelling through the heads. It is most likely not the cause of your no start issues, but if there is oil or coolant on the plugs, it could cause them to misfire. The thing about a bad head gasket is that sometimes the symptoms are not that blatant and nobody knows to look at them. Your friend was using a more basic approach to diagnosing the problem by looking at the plugs, and as a result, found signs of a problem. However, mechanics will typically look at diagnostic codes and troubleshoot from there. Again, if the symptoms aren't blatant, it's easy for anyone to not diagnose a head gasket problem.

 

[crunchie_frog]

I am sorry you have spent so much in repair costs with poor results. It sounds to me like your friend has diagnosed the head gasket problem as likely being the primary culprit to your issues for no start. Coolant and or excessive oil or both cylinders could prevent starting As for the DPFE sensor, shop that installed it should check it for you for free seeing as how they just replaced it. But given their history of doing things that did not fix your problem, that might not be a good idea.

I would not allow a shop to work on my vehicle unless they give me a guarantee their work will repair the problem. Hence, no shop will work on my car because they will not do that. Like in your case, they do a lot of things that may be needed or they can justify as needed but it is not the source of the problem. You would have done fine without the oil change, PCM update, and sounds like DPFE sensor replacement.

My two cents is to try to find a good shop (much easier said than done) and get them to confirm the head gasket failure. I think Car Talk has recommended shops and probably Angie's List has some shops they endorse/recommend. The head gasket repair will cost you though, and after that, let them diagnose and repair your DPFE sensor issues and misfires, which they should be able to do pretty easily.

An EGR valve recirculates exhaust gases into the intake. I know, doesn't sound good and really is not (you can bet NASCAR engines don't have this), thank the EPA. The DPFE sensor measures the flow of the exhaust into the intake and sends a signal to control the EGR valve opening to regulate the amount of exhaust gas into the intake. Too much flow, the engine will sputter and spit and run really rough or not run at all. Should not be your start up issue though, the EGR is closed on start up with no vacuum. It could be contributing to your rough running issues if the shop has installed the incorrect sensor or installed it incorrectly.

Good luck,