My wife 91 extended 4.0 auto JUST started this, SUDDENLY, yesterday evening. It had been running fine - albeit, seemed a little under powered, but smooth, and such - Saturday, and most of Sunday. We parked it out front, and let it sit. A couple of hours later, we go out to go somewhere, and the van wouldn't start...it would catch, fire, idle up to about 1300rpm, from the sound, and then, just die...kept doing this, until she started it, and applied the gas...hold ing the gas down for a few moments, then letting up, it would stay running, but the idle was VERY rough...it was definately missing on at LEAST one cylinder...

This was quite late at night, so we took my car to the only place open - Walmart - and bought the following, which I plan to do today, when I get home from work...

6 Autolite Platinum plugs
PVC valve
Air filter
Fuel filter
Gas Treatment / Injector Cleaner by Prestone
and a can of TB cleaner, to make sure it's not gunked up...

She had just recently filled the tank with 86-87 octane cheapy gas...and we're wondering if it could just be bad gas, but we've know the van needed the tune up for a while now, but she's been reluctant to buy the stuff, not wanting to spend money at that time...hard to do when you live pay check to pay check.

Since our Walmart doesn't carry plug wires, or Seafoam, I was waiting until tonight, if needed, to buy them...

Is there anything else anyone can suggest...possibly even a possible cause for this strange event? We really need this people mover, since I need my car for work, and it's a little cramped with three car-seats in the back...

 

Since money is really tight I would hold off on those parts for the moment.

It sounds more like a fuel delivery problem.

Check the oil to see if it is over filled (possibly a leaking fuel regulator)

Pressure test the fuel system, (borrow a gauge...)
(Search this forum for more detailed info on this)

Check the bellows from the throttle body to the air box to make sure a backfire didnt pop it loose..

Others here with more experience will answer shortly...

I am new to Aerostars and Fords in general... But I am learning fast...

If water in the fuel is a serious concern you can try and rock the van a few times then cycle the key on and off a few times to cycle any water off the bottom of the tank... then try to start it... The volumn of water is usually very small and settles at the pickup tube when parked.

If this was the first time the van was parked after fueling that could be a clue...

 

Try cleaning the MAF and the IAC valve first.

 

The tune up was due, so we needed to get that stuff anyway...

As for the cleaning of the MAF and a IAC, what is the safest method for this? I have the FSM, but have not seen any reference to cleaning procedure in there, and I sure as hell don't want to fry anything, and make the problem worse...

 

Sounds like a Vacuum hose popped loose......................

 

I've actually been thinking along the same lines, but I've never heard of one preventing the van from running at all, upon initial fire...

But while I'm in there doing the tune up, which she screams at me for not doing, yet also complains aboutt he cost, and lack of money, I will be ATTEMPTING to check all hoses, etc...Hopefully, it'll be an easy fix, and not cost anything else...at most, maybe so hose, or something...

 

Just to let you know I have also had a Dirty Air Filter do the same thing.
Start, Run, Die.
A bad Spark plug too.........
Your on the right track, You'll know more when you get all the stuff
you bought put on.

Jay

 

Thanks...and I'll be sure to post back what I've found...hopefully I'll find it tonight...

 

Well, here's the low down...

I pop the hood last night, and since I know it needs an air filter, etc...I go ahead and pull the old filter out, remove the intake hose, and clean the TB and the MAF...

While in here, checking the vac lines from the brake booster...that one is good...reaching from the front, everything looks good...So I reassemble everything, and remove the engine cover from inside...

Getting down on the floor, I see the main vacuum manifold (tree)...there are three bare nipples on this thing...hmmmmm....

Looking a little deeper, I find one hose loosely hanging there...trace it back to what I BELIEVE is the Cruise Control unit...runs across the top of the engine, to the passenger side, where it plugs into what looks like a sensor, with a single wire coming off of it, running around, in front of the A/C unit...

Well, I connect this hose...and start it up...still sucking wind, but running better....looking around, I find two vac caps laying on top of the tranny...plug those onto the last remaining nipples, start it up...and it's running again...

BUT, now the CEL light is lit up...WTH???? I'm thinking...double check EVERYTHING...and what do I find out...stupid me, I forgot to plug the MAF back in, after reattaching the hose...plugged back in, refired, and no more CEL...smooth idle, etc...YES!!!!

Now, I'm hapy, my wife's happy, and we actually still have a little money left in the bank, after returning all the parts we didn't need...only because we needed the money REALLY bad, or they would have been installed anyway, just to get them done...

Thanks for the help & suggestions...especially you, Jay...I was thinking something along the lines of a vac leak, since it happened so suddenly, with no warning what so ever....

When I reattached that hose, I mae sure to reroute it, so that it wouldn't get hung up on anything again, and get worked loose over time...

 

I have never had a vacuum line pop loose on me before. But after your post, I'll start looking at them things first before anything else.

Thanks for getting back to us.

 

Yeah, I hadn't either...I'd figured, MAYBE a busted one, or something...had one break on my Nissan Maxima once...never had one just "pop off" before...but the hose that came off was still flexible and supple...not hard, brittle, or cracked at all...

Weird...

 

The one time I had a vacuum line come loose was following a failed start attempt. One of those times where the engine seems to catch but then doesn't and abruptly stops, with a distinct engine judder. I suspect one or more cylinders misfire, producing backpressure through the manifold, pressurizing the vacuum lines and forcing one (or more) loose.