1989 Town Car chugging & hard to start. Help!

[DerekTheGreat]

Hello everybody,

I'm posting this on behalf of Ashley; Yesterday I was able to have her car scanned as the CEL popped on while driving home. Code PO304: Cylinder 4 misfire detected. Scanner detected it twice. The CEL is starting to pop on more often and sometimes when it does the car has a chug under slight loads (makes sense if only 7/8 cylinders are firing) and in neutral or park the idle is higher than usual. Car is also hard to start, has been since she bought it. Sometimes it fires right up, other times you gotta crank it for up to 5 seconds but once it fires it runs great and smooth, up until the CEL pops on.

What we've done to it so far is new plugs, wires, cap & we swapped out the TFI module with a knock-off brand found in a boneyard. Car started up better & consistently but after a week or so it's like it went back to it's old ways. Hell, that could be why the car is worse now. So we're thinking we should swap that out again with a new Motorcraft unit. What else should we look into? What could be causing the plug to foul out or not fire???

Best regards!

[miamibob]

I'd check the plug and wire. Replace if not sure. Could always be a bad/clogged injector but start with the simple stuff first!

[DerekTheGreat]

Ok, thanks bob!
Where is cylinder #4, the one on the driver's side closest to the firewall?

She paid our mechanic dude to do some fancy injector cleaning some months back but that didn't help the issue any. I've heard these things foul plugs due to bad valve stem seals?? Sometimes the thing runs great with no issues at all, other times it gets fussy..

[miamibob]

IIRC it is rear PASS side.

[sly]

passenger side is 1-4 nose to firewall and driver side is the rest. Make sure the wire isn't resting on the exhaust and that it's not coated in oil from a leaky valve cover and seated on the plug good. If all that checks out, you may need new plugs/wires/cap/rotor. The box townies don't usually have the valve seal issue. That's the 4.6L engine up to 95 that's notorious for that.

[VicCrownVic]

IIRC it is rear PASS side.

Yes, #4 is rear pass side.

Recheck the connection to the sparkplug and distributor, since you just replace the sparkplugs, wires, cap & rotor it could just be a loose connection.
I would think if the TFI or the pickup inside the distributor was going that the problem would not be limited to just one cylinder but if everything looks good you could find a whole distributor at the JY try swapping it in.

[DerekTheGreat]

Thanks for the replies fellas!

So cylinders 5-8 are on the driver's side? Allllrighty then. Wires, cap n plugs are all new but the wires are some knock off brand, not Motorcraft like I would've wanted. I'll certainly check the plug and it's connections out now that I know which one it is.

VicCrownVic,
Those are my thoughts exactly. No wonder finding a TFI module is so hard, everyone just robs the entire distributer haha. That's the only reason Ash and I went with the damn knock off. I.. used dielectric grease on it when I put it in....

[gadget73]

What car are we talking about here? You can't get a PO anything code on a box Towncar. That pre-dates the PO stuff by a decade. It cannot detect individual cylinder misfires either. EEC-IV Fords of this era have a 2 digit self-test code, and none of them are misfire codes. Auto parts stores can't scan them either as far as I've ever seen. Their scanners do OBD-II only, which is 1996+

[DerekTheGreat]

Ash's '89 Town Car...
I thought that was too good to be true, maybe just code 34 only?? I even said to the dude, "It's smart enough to know which cylinder is misfiring?" Figured it has a knock sensor??? Good thing we didn't buy that scanner they have because I didn't like the idea of the yellow sunpro one for EEC-IV and it's little red light...

[miamibob]

There are OBD 1 scanners available for under $60 (and less). Wouldn't be a bad thing to have...

[L1011tristar17]

As far as I know, the 89 Town Car doesn't have a knock sensor. The OBD I system can do a cylinder balance test with the scanner plugged in during KOER mode. If the misfire is really bad on one cylinder (bad injector or low compression) it will let you know. I don't know what the tolerances for the test are.

Here's a scanner for sale on ebay. Most auto parts stores carry these on their shelves too:

http://www.ebay.com/itm/FORD-CODE-READER-TOOL-SCANNER-DIAGNOSTIC-SCAN-OBD-CAN-/330759724842?hash=item4d02d0df2a&item=330759724842&pt=Motors_Automotive_Tools&vxp=mtr

A lot more useful than just a blinking red light IMO.

[DerekTheGreat]

Thanks L1011tristar17, that's a nice scanner. To think we almost pushed the button on the red blinking light type..
Like the other guys said I don't think it's a misfire, seems like it should be all the time when it's not. Seems to happen right as the thing reaches operating temp and then it acts dumb for about 10 minutes but after that all is normal.

[pantera77]

Here's a scanner for sale on ebay. Most auto parts stores carry these on their shelves too:

http://www.ebay.com/itm/FORD-CODE-READER-TOOL-SCANNER-DIAGNOSTIC-SCAN-OBD-CAN-/330759724842?hash=item4d02d0df2a&item=330759724842&pt=Motors_Automotive_Tools&vxp=mtr

Just so you know, you can get that for half the price from Jegs with free shipping.

http://www.ebay.com/itm/400752534268?_trksid=p2060778.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

But yes, screw the stupid blinking light testers, they do nothing you can't do with a paperclip.

34 is for the EGR valve position sensor, so it's most likely a bad sensor or something EGR related.

http://oldfuelinjection.packrad.net/page46.html

[gadget73]

If you don't want to spend much money, but have some wire, try this out:

http://www.thorssell.net/hbook/eectest.html

if you have a working check engine light, you do not need the test light. If no CEL, then the test light is what you count blinks with. Same thing as the $60 flashy light thing without spending the money. If you're buying a code scanner, get one with a display. They can be had for the same money.


Code 34 might indicate a chunk of crap sticking the EGR valve open. That will make it run stupidly. Leaky vacuum lines will do it too. Pull the upper intake and replace the lines if you hven't yet.

[DerekTheGreat]

Gadget,
Look at pantera's signature. Seems to indicate a nice garage with electricity, warmth, shelter from the rain, space and plenty of tools. Ashley and I are equipped with a single car garage that is being whored by my Firebird. This garage should have been demolished ten years ago. Has no power, space or tools. We get by with one of those 99 piece tool sets from Home De-pot and a tackle box which contains miscellaneous tools we've accumulated out of necessity lol. Needless to say, the top half of that manifold will be staying put. Once we save enough to buy our own house the cool garage set up will follow. Under hood her car looks pretty nice, the vacuum lines that are visible aren't dry rotted and nasty but it is possible someone destroyed the ones under the manifold as its not like we can see them. Ashley wants to do the HO swap in the future so I'm not sure how much money we want to throw at the NoPo when it could go towards the swap instead.. We'll pick up that scanner (Thanks Pantera for finding a cheaper one) and disconnect the vacuum line & plug it to see if the EGR is to blame. Right now her battery is completely dead for whatever reason and with all the rain we're getting it will have to wait until tomorrow..

Thanks for the responses fellas, youve been a big help!