I’ve got a 1989 Ford E-150 conversion van has developed a stalling problem. It has a V8 5.0 engine. When the problem first occurred I felt the engine stutter and pulled off the road and as I rolled to a stop it stalled out. After letting it sit for a half hour or so it restarted and we were able to make it 40 miles into Austin, stopping about every 10 miles when we felt it start to die.
We took it to a mechanic and they replaced the MAP sensor and said that should fix the problem. When we picked the car up and started it, the engine sounded loud and it idled very roughly. We looked in the rear seat and the air filter assembly was just sitting on the floor and hadn’t been reinstalled. We pointed this out to the shop and they apologized and quickly installed it. We fired the car back up and turned on the radio which began to emit a horrible loud screech. We call the mechanic back over to look at it and he pulled out the stereo and checked the wires but couldn’t seem to figure out what was wrong. Here I must digress and state that the radio was home wired to a 500W amp by the previous owner and although it worked fine the wiring was ineptly done and the amp was powered directly from the battery so we’d had a switch installed under the dash to cut power to the amp when the car was turned off so that it wouldn’t drain the battery. The mechanic said he’d need more time to work on the radio and that he’d try to do it “as cheaply as possible” which immediately raised as red flag as the radio had been working fine when we dropped it off. Since we didn’t want to be charged extra for the radio fix we decided to just drive it back to our friends house and see if we could fix the radio ourselves.
About 3 miles from the shop the car stalled out again with the same symptoms we’d brought it in for. We had it towed back to the shop which was closed for the evening and left them a note describing what had happened and requesting that they fix the stalling problem and the radio as well. When we went to lock up the car we also noticed that the power locks no longer worked and we added that to our list. The next morning we called them first thing and they promised to get to the bottom of the problem. After delaying till the end of the day they said that it seemed like the catalytic converter was clogged and would have to be replaced. They explained that the bad MAP sensor was probably making the car run rich which had resulted in the clogging of the catalytic converter. This seemed to make sense and they said that they didn’t do the cat replacement themselves but that they worked with a muffler shop that could do the repair for $385 which was a discounted rate since they sent them a lot of business. The owner of the shop himself assured us that the catalytic converter was definitely bad and that while he couldn’t guarantee that would fix the problem it would definitely need to be replaced. That sounded fair enough (we called another muffler shop and got a quote of $450) so we went ahead and asked them to have that done the next day. They also said that they had fixed the radio by rewiring it direct to the speakers and cutting out our amp in the back (which we had asked them not to do) and that the power locks were just the result of a bad fuse.
The next day we called them several times and were assured that the car was going to be fixed within an hour or two, etc, etc, until it was nearly closing time and they finally called us and told us that the muffler shop had looked at it and it didn’t need a catalytic converter after all and that it was actually the muffler that was bad. They said the muffler had rusted out and collapsed inside and that the exhaust was trapped causing pressure to build up which was making the car stall out. We were a little skeptical since they had previously assured us the cat needed to be replaced and now they were telling us it was OK but felt like we had little choice in the matter since they had already cut into the pipe and removed the old muffler. They assured us that the muffler replacement would be cheaper than the catalytic converter anyways so we figured we might as well do it. They called us right before closing time Friday afternoon and told us that it was ready and had been test driven and everything was OK. When we arrived we paid the bill for the new muffler ($300!) and started the car up the idle did sound better and it was much quieter but the radio didn’t work at all. The owner came and fiddled with the wires for another half hour or so before finally tracing it to the drivers side door speaker wire which was shorting out somewhere inside the dash. He fixed it and we went on our way.
As we began driving out of Austin I noticed that the car felt as though it had lost some power and it seemed to be struggling, especially on hills but I thought maybe I was just being overly sensitive. About 60 miles north of Austin we felt the car start to hiccup and we immediately pulled into a gas station where it stalled out as we pulled next to the pump. We let it sit for 20 minutes or so and tried to restart it with no success. Eventually we were able to get it to drive a few blocks to a better parking spot where we left it for the night. The next day we had a mobile mechanic come look at it. When we told him the other shop had charged us $300 for the muffler he said ?wow, they really screwed you? and that the repair shouldn?t have cost much more than $100 especially since they just replaced the muffler itself not the whole tailpipe assembly. He checked a few things and pulled the temperature sensor which should have made the engine turn off and instead it kept running which he said meant the car was probably operating in “limp home mode” which might also explain the lack of power. After spending around an hour poking around and driving it around the block we couldn?t get it to stall. Overall he said he suspected either a bad master fuel pump or a bad computer and suggested that we get those parts at a junkyard for cheap and see if it fixed the problem. The other potential suspect he mentioned was the fuel filter or a bad coil. Since the car seemed to be running we figured we’d try and make it back to Austin and deal with the problem there. Driving back the weather was much colder and although it felt like the van was running poorly and misfiring it never stalled out and we were able to make it back to the city.
At this point we don’t want to put much money into the van but it seems like a waste to have to sell it at a big loss since it’s only marginally drivable.
Any thoughts?
More details: van has about 86,000 miles. Recently had a tuneup with new plugs and wires and air filter installed. Starter crapped out a month ago and was replaced. Not sure what mileage it’s getting now but it was getting around 14.5 mpg highway before the stalling problem developed. Check engine light does not come on when this happens.
This should be a TFI ignition module vehicle and failures of this module are very common. Symptoms can vary but what you describe does point to a common TFI failure.
These failures are heat related and the warmer the weather the more common the problem is.
The repair is fairly cheap and easy to do. The TFI is the little gray module on the side of the distributor and testing it is pointless. It may test fine a dozen times in a row and still be faulty. If the module is changed you MUST use the special electrolytic grease that comes with the new module or the new module may fail quickly.
For more info on TFI do a net search for “TFI Settlement” and that should fill you in on the hows and whys of this problem. Hope that helps.
Hrmm. Very interesting. I checked out this description here: http://www.coolcats.net/tech/troubleshooting/tfi.html which lists the 1984-91 E-150 Vans (5.0L) as being affected by this issue. Any idea where the part is located specifically on these vans? Or what it looks like? Thanks!
It should look like this and is mounted on the side of the distributor just underneath the distributor cap. It’s about 3" long.
http://www.oreillyauto.com/site/c/detail/MPI0/27019.oap?pt=02801&ppt=C0334
These are easy to change if you choose to do it yourself. There are 2 hidden screws that hold it on and these are sunken down in the 2 holes on the side of the module. To access those screws there is a special tool but it can be done without that. You will need a 4MM nut driver or preferably a 4MM or 7/32 deep socket.
Unplug the wire connector and once the module is off scrap any gunk off of the distributor surface where the module was mounted.
The new module will come with a tube of special grease. Apply this to the new module before intalling it and plug the wire connector back onto it.
Try to do this without having to loosen the distributor and rotating it. This will save having to put a timing light on it to recheck the ignition timing. In the event you do rotate the distributor make sure that if you or someone else checks the timing they do it with the SPOUT connector unplugged. Failure to do this will throw the timing off quite a bit. (SPOUT connector is located near the distributor and is basically a plug in the end of a wire lead.)
It’s a pretty simple job really. Those modules first appeared in '84 I think on some Lincolns and by '85 they were widespread before disappearing in the mid 90s or so.
They’re also a very common problem and especially so in areas with a hotter climates. I’m in OK and have been on the side of the road a couple of times due to these things. Hope that helps.
I have some idea because you said 84 to 91. There should be a great big ignition module that looks like a die-cast aluminum box with fin-like ridges on it. When the engine loses power, the thing should be hot. It used to cost $20 to replace it.
If you have one, the parts place may ask if it is blue grommet or black grommet where the wires go into it. It will look black at first because it is dirty. The underside should be cleaner and might show the true color which should be blue. It should be somewhere on the firewall or fender; I never saw where it was in a van but it was just under the hood on the upper left side of the engine compartment on a pickup truck.
When I changed mine which was doing the same thing as yours, I never had that problem again. I also changed the electronics in the distributor since I was in the working mood but I’m about certain that a hot module wasn’t good.
If you have the little gray box thing on the side of the distributor, you won’t have what I described, and you should change that little gray box.
I went ahead and picked up a new TFI module and the removal tool but I’m having trouble removing the rear screw. I can’t reach it without rotating the distributor and I’m having trouble doing that. I’m not sure which bolt to loosen to rotate the distributor- there’s a bolt (1/2 inch) below near where the TFI sticks out which I assume is the one but I’m having a hell of a time getting to it in a position that has any torque. Also I know I’m supposed to mark the distributor so that I don’t mess up the timing but I’m unclear where exactly I need to mark. Does anyone have a photo or diagram that might shed some light on this? Thanks
Sometimes a distributor wrench (or some innovative acrobatics) is needed to access the distributor hold down bolt.
If you must rotate the distributor then take a Sharpie pen and make a mark on both the cap or distributor housing and a fixed point on the intake manifold, etc. Aligning those 2 marks should put you back real close on the timing and odds are that it will be close enough to not be of any concern.
Off the top of my head I could not remember if anything on the 5.0 interfered with one of the module screws or not. I know on my old Mercury Sable that one of them was near impossible to access without rotating the distributor, with said Sable leaving me on the side of the road a few times with an overheated module.
You would have thought that someone would have just designed the stupid thing with screw heads that are visible and accessible instead of burying them in a deep well.
Well I finally installed the new TFI module after rotating the distributor and snipping off part of the plastic of the old module so I could remove the rear screw. I then picked up a new longer phillips screw and put a spacer on it so it sits just outside the body of the module and can be reached with an angled screw driver. Started the car up and idled it for an hour and it never stalled so I drove it around town in stop and go traffic, took it on the freeway, and rolled around for an hour and it ran fine. Brought it back home and let it idle for another 30 minutes or so and then it stalled out just like before.
I guess it’s back to the drawing board. Starting to run out of options. High pressure fuel pump / filter / ignition coil / computer…? What else could it be?
If the stalling is only happening at idle then the possibility of a vacuum leak or Idle Air Valve problem is a possibility.
The best method of checking for a vac. leak is by connecting a vacuum gauge to an intake manifold nipple. Something to keep in mind is that a number of heater/A/C functions in the dashboard are controlled by vacuum. This means the problem could be dependent upon the position of the mode control. (FLOOR, DEFROST, etc.)
Vacuum pods control various doors in the heater ductwork so it’s possible that you could have a vacuum leak in say the DEF position and not the MAX AC, FLOOR, or whatever.
Watching the vacuum gauge while the engine is at idle and moving the mode control around could reveal this. Manifold vacuum will vary based on a number of factors but generally you look for 17-20" of vacuum with a rock steady needle at idle.
(A vacuum gauge is cheap, easy to use, and one of the handiest tools on the planet. I would highly recommend buying one since you do your own work and what’s a shame is that the majority of pro mechanics apparently do not own one or choose to use them. They are invaluable in my opinion.)
Idle Air Valves are also a common problem. Sometimes cleaning them can help; other times it may need to be replaced. It’s easy enough to remove and clean on the 5.0 though.
There’s a few more obscure things that it could be but I hope some of that helps and feel free to post back. Maybe we can wade through this thing and get it ironed out.
Originally it was stalling while driving, or to be more precise it would cough, lose power, the gas pedal would have no effect, and I would pull off the road just in time for it to stall out. After the replacement of the MAP sensor & muffler it stalled out in almost the same manner although it did make it further (about 70 miles) before stalling – that day was much cooler so it might have had more to do with the temperature than the new muffler.
Normally when you turn the key you can hear what I thought was the high pressure fuel pump (but maybe I was mistaking the noise of the starter motor) make an rrrrgggggh noise as it powers up. After the call stalled out today I turned the key and listened for the rggg noise but didn’t hear anything. If you try and restart the car right after it’s stalled it will sometimes catch for a minute but run very rough, coughing, shaking, and sputtering and will die within 10-15 seconds even if you try to give it gas. Once the car cools down it will start right up but usually stalls out quickly unless you let it sit for several hours or overnight.
So far the research I’ve done has pointed to the following options as possible causes of stalling:
pickup AKA PIP sensor (usually won’t start at all but can fail intermittently)
ignition coil
MAF sensor (I don’t think the '89 models have this, do they?)
fuel pump
fuel pump relay
fuel filter
throttle position sensor
clogged EGR valve
Idle Air Control Valve
vacuum leak
02 sensor
coolant sensor
Sheesh, looking at that list makes me think maybe I should just get rid of the damn thing.
P.S. I had to move the distributor to remove the TFI module so I marked it and the engine block and lined them up when I put it back in position. Is that likely to throw the timing off enough to cause trouble?
If the distributor is very close to the original position then timing should not be an issue unless someone has dinked with the distributor in the past.
This engine will not have a MAF sensor as it is a speed density engine so that is not an issue either.
That list may seem overwhelming but it’s really not that bad. The iffy part is the bit originally about stalling out at speed and now it stalls at idle.
If it is only stalling at idle then I’d be leaning towards an Idle Air Valve problem, vacuum leak, possible EGR sticking open, and grasping a bit here; the PIP problem.
Can you pull codes on this van? It can be done with a cheap code reader (20 bucks) or a VOM. This requires that you carefully watch the flashing light or needle twitches all depending on which method you use. There is a memory function and while the control system is not nearly as precise as the OBD II there’s the possibility a code(s) could be present.
What would I do at this point if the van were mine? Stick a vacuum gauge on it (even an EGR sticking would show up on this) and check for any codes that may be present.
The part about the fuel pump also sounds like the fuel pump could be suspect but that should show up on the open road also.
Another more obscure cause could be the electrical part of the ignition switch failing.
Off the top of my head I don’t know if your van is wired this way but many Fords have run their blower motor (cabin heat and AC) current through the ign. switch. With age a blower motor draws much more current and over time this can burn the contacts in the ignition switch and lead to a stalling engine or one that will not start.
Sorry I can’t be more precise here as there are too many unknowns and the symptom has a bit of variance. That is why I can’t nail it down more accurately. Hope this helps anyway.
Just dug up the invoice from when we first took the van in-- they pulled the codes then and listed the following:
22 Map sensor
32 EGR position pressure
21 Engine coolant temp high or low
That time they replaced the MAP sensor which didn’t affect the problem at all. They seemed to think that the EGR issue wouldn’t affect drive-ability but I’m not at all convinced they knew what they were talking about.
An EGR that is acting up could cause a surge at speed while on the road and an EGR that is sticking in the open position can cause a very rough idle or a refusal to idle at all. It should not cause an engine to die while at speed.
The MAP sensor will generally not cause problems like you’re having. It’s possible that the ECT sensor (engine coolant temp) could possibly cause this if the sensor is really acting up instead of being just borderline iffy.
(The ECT can be tested with a VOM and resistance will vary based on engine temperature)
If you decide to replace the ECT instead of testing it then make sure you replace the right part. There’s an ECT sensor (the part being discussed) and there’s an engine coolant temp SENDER which is something entirely different. The latter controls the dashboard temp gauge.
You might consider clearing the codes, operating the van for a while and then retesting for codes to see what appears.
Do you have a code reader or VOM so as to test for codes yourself? (If you do, the codes appear in several modes.
Key on, engine off with any codes being shown followed by a pause and then a second set which is referred to as continuous monitor, or the “wiggle test”.
Key on, engine running which reveals any fault existing while the engine is operating.
To clear codes you must exit the test while the continuous monitor test is running.
Drove it for a few hours today until it stalled out and then took it to a shop so they could witness it happen. They tested the fuel pressure and said it was low and that the signs pointed to a bad high pressure fuel pump but after changing that out along with the fuel filter the stalling problem resurfaced during a test drive. These guys were cool and put our old fuel pump back on and didn’t charge us for their time. Planning on bringing it back to them tomorrow so they can try and puzzle it out.
Here’s the riddle - it is definitely stalling at speed or at least you lose power and then it eventually stalls out when you pull over. The fuel pressure tested low after it stalled out even with the new pump. The mechanic seemed pretty sure that it was some sort of fuel delivery problem. We’ve now ruled out MAP sensor, catalytic converter, muffler, TFI module, fuel filter, and high pressure fuel pump. Since it won’t restart after stalling even if you switch tanks that would seem to rule out a failure of the in tank fuel filters unless maybe the tank selector switch is not working and it’s stuck on the front tank.
Question first. Does this model use 2 pumps; an external high pressure pump and a low pressure in-tank pump?
Is the external pump the one they changed?
IF this is the case then maybe the in-tank low pressure pump is failing. The low pressure pump is designed to feed the high pressure pump and if the in-tank unit is getting weak and/or has a clogged sock then that could be starving the main pump for fuel.
The van has dual tanks so it’s got 3 pumps, one high pressure outside, and two low pressure pumps, one inside each tank.
Some vehicles have both low and high pressure pumps mounted together as a module in a bathtub arrangement with the entire thing inside the tank. The low pump, along with gas from the return line, keeps the tub filled and the high pressure pump draws from that pool in the tub.
I’ve got an 87 Ford with a setup like this and my SAAB uses the same arrangement.
It’s quite possible anyway for a low pressure pump to become weak or have a clogged sock and it’s also quite possible for even a low pressure pump to kind of fade in and out a bit.
That’s about my best educated theories (a.k.a. wild axx guesses) anyway. 
OK. Some interesting developments here. The guys at the shop said that it appears to be an electrical problem – something is overheating resulting low current to the high pressure fuel pump which causes it to stop working. They also said they checked the fuel pressure regulator and that it was fine. They suggested we take it to an electrical specialist since they don’t specialize in those type of repairs. We stopped by one place and he suggested that it might be cheaper to just install an electric fuel pump that would bypass the HP fuel pump rather than spend a bunch of time trying to isolate the bad wire / part. Any thoughts?
EDIT: Talked to another electric shop and they said the after market electric fuel pumps are pretty crappy and don’t last long.
I don’t agree that aftermarket fuel pumps are crappy after having used a lot of them with no problems.
The only fuel pump I would not trust would be a no-name aftermarket such as might be found on eBay. After buying one of these once and knowing of a few other people who did the same they would not be recommended by me as they all failed within 6 months.
A name such as Airtex, Walbro, etc. will be fine and these are available everywhere.
I’ll see if I can rummage up a schematic for this van and go over it. My bookcase has a number of Ford schematics for various 5.0s but I’d like to make sure the van is not different.
Some Fords of this era used a control module through which the fuel pump, A/C compressor, and cooling fan wiring is routed. This is essentially a big box of relays and at times there have been problems not so much with the relays inside but the wire plug that attaches to the box. You might look underneath the hood for a small flat box about 5" square with a couple of dozen small wires in a harness going to it.
Some Fords mount these on top of the radiator support and some on top of the inner fender.
I may not be back on this forum until tomorrow night as I’ve got to go somewhere bright and early in the morning and will be back whenever; preferably a fairly quick whenever.