Focus Fanatics Forum banner

Status
Not open for further replies.
1 - 7 of 7 Posts

·
Registered
Joined
·
47 Posts
Discussion Starter #1
This is what I've got:

-2004 2.3 PZEV MTX

Problem:

When I bought the car it had 13,500 miles on it. It ran fine for about 2k miles then it started stumbling reeaaaaallllllyyyyy bad. I replaced the plugs, which didn't look all that bad (no need to replace wires b/c it has COP), and the fuel filter and used some B12 Chemtool in the gas, and cleaned the TB but it still didn't fix it. I finally took it to the dealership and it took them forever to diagnose the problem. They looked into the fuel pump, maf sensor, tps, intake, tb, and plugs (which were new) and couldn't figure out the problem. After about 1 1/2 months they told me it was the MAF. I put on a CAI (with a 2.5" section for the MAF to retain stock readings) and bought a new MAF and TPS because upon inspection, the stock air box had water in the bottom of it because the people who owned it before me somehow damaged part of the airbox which allowed moisture into the system when it rained and the stock MAF actually had water droplet stains on it. Water=stumble they told me and that the parts I bought (because they couldn't warranty the parts due to someone damaging them) would fix it. Well, mucho dinero later, none of that fixed the problem. Finally after taking it to another Ford dealership, one of the techs found out what was "wrong". His diagnosis: the PZEV motor takes a very specific spark plug, "....that only Ford makes....". The autolites that we're in it when it began stumbling, which I replaced with more Autolites, apparently aren't sufficient for the PZEV motor. Ford said that even though the Autolite plugs say they're compatible with the PZEV, they're not. They replaced the Autolites with Ford's "special" spark plugs and the problem went away. [:)][:)][:)][:)][:)][:)]Notice: before ANY work was done, I disconnected the negative and positive terminals multiple times and the problem never stoped. Ford searched for engine codes and ran a computer diagnostics on it mulitple times, and I even took them on a ride along (in which I drove normal for a few minutes/hard for a few/normal for a few to cool down) with a diagnostics laptop hooked up to my car, and nothing ever showed up. They even reset the A/F ratio (was running around 10% rich because of CAI I'm guessing) and all other parameters just for the heck of it, even though they all looked fine. The car only threw a light once and it was because of,"...high sulfur readings..." I ran a full tank of premium with a couple bottles of octane booster one night shortly before the light came on, but its never come on other than that. A few other times I had run premium, but not often. Ford said the readings were from the premium gas because the fuel pumps aren't made to take it and that it could actually damage it. Check this out, the CEL doesn't even come on and I have no exhaust from my flex pipe back. The last O2 sensor is about 12-16 inches away from the exhaust exit, which is the flex pipe, (on the PZEV there is no O2 sensor after the CAT) at least until I have straight pipes put on this week to make a rear exit instead of it being under the car (and yes I know, bad idea for it being under the car but it was only for a few days and I'm not driving the car much). Is that weird that the CEL isn't going off? Could it be reading fine because of the 1st CAT in the manifold? I figure if it reads fine, why put another CAT on for more restriction?[:)][:)][:)][:)][:)][:)] Basically, whatever the dealership did with the plugs made the stumbling problem go away completely, but now...........

Fast forward 3k miles later...the car is having the same problem. What the heck could be causing this to happen? Timing? As far as I know the car was never tuned. Would a tune help it? Could it be water damage? Why would it burn plugs so fast? Why did the problem disappear completely then come back if it is water damage? Ford did find records where the car had been taken to a mechanic, other than Ford, for this same issue mulitple times when an older couple owned it before me. Why would you take a car that is under warranty to a mechanic other than Ford? Why would you pay for your own mechanic? This is crappy, because I asked the couple if they ever had any problems with the car and they said it was perfect....liars.

Thanks for any help
 

·
Registered
Joined
·
47 Posts
Discussion Starter #3
Also, it's fine when I'm getting on it hard above 2500 rpm, but keeping constant throttle or barely pressing it will cause it to stumble.
 

·
on thin air
Joined
·
3,671 Posts
the symptoms you are describing are definitely in line with plug issues again...the part throttle/steady gas stumble and running strong at higher rpms....I had the same issues from trying different plugs. Eventually went back to the Motorcraft plats that came stock with the car and have had no issues since (thank god).

Why it keeps burning the plugs - well, I dunno bout that one really. What do they look like when you pull them? Are they corroded, oily, burned? Thats going to be a good indicator on where to start looking.

On another note, I can kinda understand why someone would take the car to someone they TRUST vs. taking it to the dealership under warranty. They can be pretty slimey at times.
 

·
Registered
Joined
·
3 Posts
I would guess that water is getting in with the plugs and fouling them that why a plug change would work for a while then just mess up. One thing to check is whether the plug wires have a good seal on the valve cover. Also it could help me diagnose if I knew if it had a check engine on.
 

·
C2H5OH
Joined
·
11,867 Posts
Post a picture of said "burnt" spark plug, actually take good pic's of all 4. I'm willing to bet it's not a plug issue at all, you can probably guess what I'm thinking though.
 
1 - 7 of 7 Posts
Status
Not open for further replies.
Top