89 LX quits 7 mins after starting; won't restart for several hours.

[AlaskaFestivaGuy]

One of my 89 LXs (carbed, of course) starts normally, idles high (2700 or so) for a few mins, then kicks down after 5 mins to about 2000.

A few minutes later, it just quits and won't restart for hours (though it does crank).

Replacing the battery had no effect.

Ignition wires seem in good shape (I bought the car a year ago and had a valve job done at that time with 110,000 miles); I suspect wires/etc. were new at purchase.

Emission hoses seem in good shape and all connected.

What might this be? Some failed sensor that is only monitored after warm-up is done?

This started a month ago. In the months prior to that, I'd driven it up to 1,000 miles from home without worry.

Note: The hose from air intake snout to exhaust manifold shield is missing; new one expected to arrive in a few days. I don't recall when it went missing.

[Festy46]

It could be the ignition module inside the distributor. It quits when it gets hot and the engine has to get cold for it to work again.

[AlaskaFestivaGuy]

Festy46 ... Is that also called the "condenser?"

[WmWatt]

That large hose/duct lets warm air into the carburettor intake when the car first stars up. There's a baffle with a thermostat (simple bi-metal strip?) connected to a short air hose that closes after the engine warms up. Don't know if it's your high revs problem. I think high revs is a bad air/fule mixture. Too much fule or not enough air means engine runs rich producing revs. Automatic choke restricts air intake at first so engine doesn't stall whjich is why engine revs high until choke disengages. One thing you might try is cleaning the carburettor and external linkages (throttle, choke) with a spray can of carb cleaner. I do it once a year as part of annual tuneup. If it does you no good, it will do you no harm.

[AlaskaFestivaGuy]

WmWatt,

This problem came on, literally, overnight. Up until a month ago, except for longer-than-expected times for the RPM to come down on warmup, the car ran flawlessly. Then, it simply quit one day out on the freeway and I had to spend $130 for a four mile tow home. It seems odd to think that dirty parts would cause such a sudden change in behavior.

[FestYboy]

Sounds like your carb bowl isn't filling as it should and add a vac leak to add to the excessive rpms. A good running carb car should cold start at 1200 and drop to 650 at warm idle. I used to get Scrappy to idle at 200 smoothly.
Check fuel pressure and vacuum and ignition timing (as well as the mechanical timing) also look for vac leaks. Correct all before touching the carb

[Greywolf]

Since it's carbureted, to me it sounds almost like a vacuum leak. ~But maybe not!!!

Because it quits, and then comes back after a while I really don't think it's ignition because when wires fail they just quit.

For some reason I am thinking that if you have another carb, try swapping them out and see what it does.

Some carbs have air bleeds that can affect idle speed. But the big thing I think may be involved is that the fuel level float system is buggered some way. Check your fuel filter(s). Two of these possibles might be proven by swapping out the carb to test it.

*REASON: If you have bad fuel flow from an old filter, the carb won't get enough to run. The symptoms are the same as a plugged float needle and seat, but when floats go bad they usually cause flooding - don't they?

If that does the trick - take a long and intensive look at the carb that came off. If anyone from here is near you and has a spare carb, or if you have one, that can be done easy.

Carbs also have a "FAST IDLE CAM", and if that has a problem your idle will go nuts. Look over your carb linkage and see if there is any sign of missing or loose pieces.

Thinking over what I just wrote, a vacuum gauge and a fuel pressure gauge are the two most helpful tools you can get and become good with.


If I was a betting man - I'd wager your float bowl was running dry and your idle cam was jacked somehow.


Oh and BTW: Dirt and crud are a carburetors worst enemy

They can make linkages stick, stuff not open or close right, and clog fuel ports. The only thing worse is corrosion


Considering all of these thoughts together - I suggest you replace your fuel filter(s) FIRST, and then see what happens.

~You should do that anyway, after a lot of miles. GAS TODAY is CRUMMY quality, especially since ethanol was introduced


*Something else I oughta mention, is that my favorite secret weapon is Berrymans B12, not in a spray can but added to the gas at double strength.

[AlaskaFestivaGuy]

I do not have a spare carb, at least not one that's not installed in another LX.

I will, however, immediately replace the fuel filter.

I'm eventually going to upgrade all of my LXs to Fi, so would rather not drop hundreds of dollars on a new carb.

[Greywolf]

If you convert to FI you're looking at changing the in tank fuel pump, ECM, possibly the harness and everything.

EFI runs at a much higher pressure (my Swift experiences gave me a lot of insight there) so a lot of things change.

Study that carefully before you decide to go there.


It might be best to go with a carb rebuild kit, or swap out the carb for a weber down draft or whatever fits.


"HUNDREDS OF DOLLARS" for a new carb is just not real. You'll spend a lot more than that on a conversion, unless you have a donor car

I don't have a manual yet for these, but experience tells me EFI runs at a pressure of 20 - 30 PSI, and a carb fuel pump doesn't deliver that.

Carbs run at around 7 PSI, so that means you would have to convert the entire fuel system to higher pressure.


*And that reminds me, as tight as I have to hang onto cash right now I need to send off for a Festiva service manual.

~CIAO

[WmWatt]

For the engine cutting out I'd look at what Festy46 wrote above. You wrote the igntion seems okay but when it won't start you could pull a spark plug wire and hold it 1/4" from the block to check for spark while cranking. It would seem odd for the carburettor to become suddenly dirty but something in the fuel could get in there and gave it a heart attack. The suggestions that the float bowl is suddenly acting up could also be dirt. When antique cars were new drivers would sometimes have to blow through the fuel lines to get their engines running. Hope it's something simple. I'd check what else I could before thinking about opening up the carburettor.

[zoe60]

When mine did that it was the ignition control module like festy46 said. It is inside the distributor. There's a guy on Ebay who usually has them for around $60.00. If not from him they are pretty expensive. Good luck! Doesn't seem like it would suddenly quit when it got warm if it were a fuel delivery issue.

[Festy46]

Festy46 ... Is that also called the "condenser?"

No, the ignition module is different. Here's a link to a picture of the ignition module.

http://www.rockauto.com/en/catalog/ford,1989,festiva,1.3l+l4,1128103,ignition,ignition+control+module+(icm),7172?a=Referer+www.google.com+URL+%2Fen%2Fcatalog%2Fford

[AlaskaFestivaGuy]

I'll be trying a new fuel filter today and also check for spark. I'm not touching the carb until I've ruled out other causes.

Yes, I'm well aware of the effort to convert carb to FI. These are all pristine (zero corrosion) inside-and-out LXs, and I already have a bunch of low-mileage FI donors. I'll rent some well-lit warehouse space for a year or so and end up with at least four like-new (new all-around bushings, driveshafts, bearings, brakes, etc while I'm at it) FI'd LXs and a well-organized supply of spare parts.

[WmWatt]

The old name for the ignition control module (ICM) was transistorized points. Before that distributors had mechanical points and a condenser. Both were normally replaced at the same time.

[AlaskaFestivaGuy]

Well, it wasn't the fuel filter. Interestingly, it quit after 4 minutes (I timed it this time) before even doing the first RPM stepdown, perhaps because it was a bit warmer (50F) today than previous days, so it warmed up faster.

I also lifted up the air cleaner assembly and inspected as best I could many of the emission hoses. Nothing seems to have fallen apart or moved such that it's touching the block or exhaust manifold.

I'll grab someone this evening to do a spark check.