I can screw up anything...

TFrog... 1993 LX 5.0 5-speed, now with 196,600 miles.

So, lately it didn't like starting up when cold. VERY rich, too much gas smell in the exhaust, and it needed a little help with the accelerator pedal just to keep from stalling out. A little push, and the RPMs would jump to

2,000 and immediately want to fall off again. After warming up for a bit, it was (relatively) fine.

Couple of months ago, when it was in for a tune-up, the mechanic recommended swapping in a new mass air meter. Well, today, I finally decided to clean the sucker and see what happens.

Bought my new set ot Torx drivers, took out two screws and removed the MAM. Yep, two tiny little filaments, but they looked fine. Even so, I oh-so-carefully wiped the down with Q-Tips and a bit of alcohol. Sure enough, a little dirt came off of those suckers. While I was at it, I also cleaned the contacts to the MAM.

Oh-so-gently replaced the unit and went to start up the car. No go. Crank, crank, crank, but no start. Yes, the fuel pump comes on as usual, but no start. Held the gas pedal to the floor, no start.

Fine. Disconnected the battery for an hour to clear the computer. No start.

Fine. Checked the emergency fuel shut-off in the back, no start.

What the hell did I do? All I really did was take a Q-Tip to a couple of filaments, and now the car won't start...

dwight

Reply to
dwight
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"dwight" wrote in news:m8qdnQs_gfNOiCTZnZ2dnUVZ snipped-for-privacy@comcast.com:

Is the MAF wire plugged in tight? Did the coil wire slip off the distributor? Just a few thoughts.

As for the symptoms up top, have you checked the idle air bypass on the throttle body? That thing could be cruddy.

Joe Calypso Green '93 5.0 LX AOD hatch with a few goodies Black '03 Dakota 5.9 R/T CC

Reply to
Joe

Well, quick and fairly inexpensive, put in a different (used or borrowed) and see what happens. You really aren't supposed to touch the filiment with anything, you may have broken it and just can't see it.

Reply to
WindsorFox

Even if the MAF goes dead the computer has a fail-safe mode to let the engine run and limp home or to a garage using temperature, BAP readings etc. Try disconnecting it all together and see if it starts. I would suggest checking all the other electrical connectors in the area of the MAF like the idle speed control valve, throttle body etc. Maybe you accidentally loosened one while messing with the MAF. I have cleaned MAF sensors many times and don't find them to be as fragile as they look. Actually the best cleaning solution I have found is brake parts cleaner. It dries with no residue and works as well as electronic parts cleaner.

Reply to
Michael Johnson, PE

I really didn't touch anything but the two screws and the clip-on connector. Really.

Very strange...

dwight

Reply to
dwight

Hmmm.... Don't think so, but I happen to know where I can get my hands on another one to try in TFrog (from CFrog). But now I'm scared to try anything before I know what happened.

I don't need TWO dead Mustangs.

dwight

Reply to
dwight

The car is trying to start, just like usual, but it seems there's no gas getting to the mix. (That's why I checked the cut-off switch.) Otherwise, everything sounds normal up to the point where it just doesn't fire.

There was only one change since I parked the car in the garage, and that was removing, cleaning, and reinstalling the mass air meter. I can't imagine any other variable in this situation...

dwight

Reply to
dwight

Did you try starting it with the MAF unplugged?

Reply to
Michael Johnson, PE

Just tried unplugged, no difference. Removed the connection to the air filter, but air flow doesn't appear to be the problem. Added gas, just in case my fuel guage is lying, no difference.

The fuel pump whines, the starter cranks, no fire. Weird.

It was running when I parked it, cleaned those two filaments, and now nothing. I hate weird.

dwight

Reply to
dwight

I believe in Simultaneous Failure and Cascading Disaster.

Cascading Disaster is when you fix one thing, but something else is now a new problem because of it.

Simultaneous Failure is when your attention is drawn to one thing, while the real problem is totally unconnected and in a different system altogether.

I suppose it's possible that, while the car was parked for a week, it suddenly developed a fuel flow problem (the fuel filter isn't THAT old, but it's possible that it was bad last week and now clogged. Stuff like that happens with an old car.)

Actually, I'm sure there are a number of reasons that the fuel isn't igniting or not reaching the combustion chamber. There's no gas smell, so I suspect the latter, rather than the former.

Ah, well... At least the mass air meter is clean.

dwight

Reply to
dwight

"dwight" wrote in news:c_SdnVlOSZylxiTZnZ2dnUVZ snipped-for-privacy@comcast.com:

I agree - it's happened to me before. My money's on something unrelated to the MAF.

Joe Calypso Green '93 5.0 LX AOD hatch with a few goodies Black '03 Dakota 5.9 R/T CC

Reply to
Joe

Same here. I had a fuel pump quit after I did a tuneup..... Drove me nuts for a week.

My advice is go back to basics and forget about the MAF. Fuel and spark.. Which one is missing? Any codes (MAF sets off codes like crazy!)

Reply to
lymee

Do you have anything to test fuel pressure? If not you can use starter fluid to tell if there is a fuel problem. Spray it into the intake and see if it fires. If it does then I bet there is a fuel delivery issue. Also, you can check the spark by unplugging a sprark plug wire and leaving a small gap (1/8"-1/16") from the end to a ground. Crank the car and see if a spark jumps across the gap.

You can swap MAF's between cars and see it that solves the problem. Unless you butchered the MAF element while cleaning it I don't see it being the problem.

Reply to
Michael Johnson, PE

Okay, what happened to me once was while working on a 88 Marquis that was my grandma's that she gave me to sell, suddenly the igniter module died in the Mustang. I was swapping parts here and there doing tests to tune the Merc and suddenly the Mustang died. I took the igniter out of the Merc and swapped and the Mustang started. So that could be a possibility. I got to where I carry a new in the glove box along with the little special made driver to change it.

Reply to
WindsorFox

Sudden unexplained no start. My guess is the TFI module.

Reply to
Richard

They usually fail when hot. You need to determine if it's missing fuel or spark.

Simultaneous Failure: I was working on an old Pontiac V8 a number of years ago. Simple problem, no spark. Found a bad rotor. No big deal, right? Replace the cap and rotor and had good spark, but it still would not start. While the guy that owned the car was cranking the crap out of it trying to get it to start the timing chain jumped. Had a worn out plastic cam gear. I'd almost bet the chain jumped and then the rotor being out of alignment with the contacts in the cap caused the failure. Try explaining that to some customer that has no idea what a spark plug is:)

Al

Reply to
Big Al

I know that you swear you didn't touch anything else. But, its very easy to. I'd check all electrical connections in and around the side of the motor you worked on. Even with a bad or disconnected MAF the car should run at least half assed.

Reply to
walt peifer

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