EFI wows, about to scrap it!

[89LincolnTWNcar]

I went thru many months of nightmares with a similar problem you are having. My ECM was throwing a code 18 though. Turned out to be the distributor/ TFI module. I tried 2TFI modules from Advance auto on my original distributor before replacing with 3 Carquest reman dizzys and finally 1 MSD probillet and had nothing but problems before finally going to the junkyard to find an old Motorcraft dizzy, which fixed all my issues... go figure!

I replaced the TPS, MAP, plugs/wires/cap/rotor, timed it perfectly, battery, alternator, swapped the ECM 3 times, put a new 22Kohm resistor in the old harness, replaced the harness, replaced the ignition switch, the alternator 3G wiring I re-did, redid all my grounds and checked all my fuel injectors, changed out the ECM relay, new EGR, checked the fuel pressure and inertia switch.....all before finding out it was the MSD Probillet dizzy/TFI combo. Hope this helps if you start to go down this road.

[DezertRunner]

Looks like I don't have to carb it yet. First thing I did was scan for codes running and not, all I could get was code 11 which is all ok, still ran like shit with spout in, great out. New distributor, battery reset, and timed again 100% fixed it and still only code after is 11. Spout is in and running like it should, woooot! When timing going by smoothness and sound about 13-14 BTC sounded the best spout in or not, so that is where I locked it. Afterwards drove about 50 miles stop and go to freeway and it is running awesome, shows an average of 21 mpg in the trip display if that is good or not, seems to me.

[adam.w.ackerman]

I get 20mpg in my 89'.


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[His Royal Ghostliness]

I went thru many months of nightmares with a similar problem you are having. My ECM was throwing a code 18 though. Turned out to be the distributor/ TFI module. I tried 2TFI modules from Advance auto on my original distributor before replacing with 3 Carquest reman dizzys and finally 1 MSD probillet and had nothing but problems before finally going to the junkyard to find an old Motorcraft dizzy, which fixed all my issues... go figure!

I replaced the TPS, MAP, plugs/wires/cap/rotor, timed it perfectly, battery, alternator, swapped the ECM 3 times, put a new 22Kohm resistor in the old harness, replaced the harness, replaced the ignition switch, the alternator 3G wiring I re-did, redid all my grounds and checked all my fuel injectors, changed out the ECM relay, new EGR, checked the fuel pressure and inertia switch.....all before finding out it was the MSD Probillet dizzy/TFI combo. Hope this helps if you start to go down this road.

Yeah, that sounds like this one problem child I worked on, and now is in someone else's shop cause she's still being a total bitch despite working perfectly for me before I surrendered her to her owner. Code 18 was what he experiences, now she has a hard time starting and runs like shit when cold. New TFI is what I'm about to suggest the shop installs, cause the one on it is new as well but from a part store and attached to the 2nd dizzy I tried, so who knows what shit is going on inside it...

DezertRunner, anything over 20mpg is good for these cars. Don't rely on the tripminder much tho, Ford has a history of making them show "optimistic" numbers, calculate your fuel usage by hand over several tanks of gas, then you'll have a more solid and reliable number.

[Kodachrome Wolf]

SEFI wise, worst mileage I've gotten was 13 MPG while the dizzy was shot, and 21 MPG on a long trip with mixed A/C. 16.5 MPG is my average figure for the wagon.

[DerekTheGreat]

Didnt you get to see creamy got most all of those things working actually efi even with a tweecer and 30lb injectors couldnt keep up even with the fuel economy my carbs have. Done a lot of thinking about does a engine realy need a big throttle body afr dropping instantly to 12.7 ish lowering air speed as its floored. A carb set up increases adds fuel to the curve as the rpms increase as needed. Basically until one goes with a hilborn style EFI there is little advantage between carbs and FI . Older ecms couldnt compute fast enough at rps over 7000.

Welp, if a dude was running a double-pumper type carb that would also cause the AFR to drop instantly as all barrels open up as soon as the gas is hammered much like a TB does. Unless it's a dedicated track/strip car its vacuum secondaries for me though. At cruise with engine up to temp I would imagine a carb could perform just as well as one of our cars. However... Carbs are mechanical and any change you want to make requires changing something within the carb. EFI, is programmable. One such advantage is to be able to turn off fuel delivery while in gear decelerating. Can't do that with a carb, least not to my knowledge. Idle circuit is still supplying fuel.. Also, a dude with a sophisticated ECM could tune the thing to lean out at part throttle cruise. Then we could get into cylinder deactivation mode, need an ECM to control that and need an engineer to explain the technical stuff as I am not an engineer. That could potentially work with a carb too, as deactivated cylinders aren't going to draw more air through the venturies... Hypothetical here. I don't hate carbs to death, but, show me the factory fuel economy numbers from a lopo with a carb on it vs lopo at factory spec, at all types of driving conditions. My money is on the LoPo. Even if you got some guy to tune the LoPo with a carb set up to mimic the LoPo as best as possible... Big selling point for me is "bump the key and go" which is something a lopo will do far longer than a carb will. Also, if the car was born with a carb I'm not against it, just against the whole "slap a carb on it" in place of what was a nice EFI system. Seems too a lot of guys make mistakes with their math due to speedometer errors, test variables & conditions and actual amount of fuel used vs pumped back into tank.

SEFI wise, worst mileage I've gotten was 13 MPG while the dizzy was shot, and 21 MPG on a long trip with mixed A/C. 16.5 MPG is my average figure for the wagon.

@ 65mph I've gotten like 24.5mpg out of my '88 Town Car. I think the timing is at 12 degrees but lately I've been hearing too much pinging under acceleration so either the quality of gas has gone down or I need to back off. Going to put it back at 10 when I get around to it. New tires have made a significant difference is fuel mileage too. Although I won't have the official comparison until the next Florida trip.

[turbo2256b]

Spent months programming and data logging creamy. Drive around data logging then figure programming changes needed then maybe spend all night making changes to charts, graphs, and or constants. Then the next day download it into the car. That went on for months. Actually ended up teaching others how to tune their rides. A real pain in the but compared to pulling 2 carbs and changing some air or fuel jetting maybe a couple hours at worst. Have done 200 some dyno runs to program one SD setup which are actually more accurate in most cases than a mass air system. Just think what that cost.
Not that I am against FI its just that to high an engine output the less chance its going to work well without going aftermarket which gets expensive.

Once I needed a better flowing intake and lost EGR the carbs actually got better fuel economy than the FI well tuned. Creamy at one point N/A needed 30 lb injectors and other settings changed that most often were done to boosted engines.

[DerekTheGreat]

Sounds thorough, how it's done. Now though, they have those self tune set-ups which dial it in close enough for a laymen like myself. That's what I'd run.

Not so sure I believe that, maybe at cruising speed but not overall. You still have that car? This the same engine or one vs the other? For comparison's sake I'd want the same engine just EFI or carb.

[86VickyLX]

DezertRunner, anything over 20mpg is good for these cars. Don't rely on the tripminder much tho, Ford has a history of making them show "optimistic" numbers, calculate your fuel usage by hand over several tanks of gas, then you'll have a more solid and reliable number.

Tripminder calculations rely on proper injector values for fuel consumption. Having incorrect data plugged into the ecm will change what the tripminder displays. Also, if the speedometer/vss is off (wrong gear, different tire size etc). it will also affect the calculations of the tripminder. I learned that from my early days of tuning. Also, in some computer strategies you can modify the pulses that the computer sends to the tripminder to alter the readings the tripminder display. 40000 pulses = 1 gallon for example can be modified to say 35000 pulses = 1 gallon used.

All that being said, average fuel economy on a stock or properly tuned setup should show proper fuel economy calculations.

[gadget73]

I kinda wonder about the pulses per gallon thing. Mark VII's are usually accurate, and stock Vics are accurate. Put a Mark VII engine and ECM in a Vic and its usually not accurate. Maybe the two ECMs have a different output.

[turbo2256b]

Sounds thorough, how it's done. Now though, they have those self tune set-ups which dial it in close enough for a laymen like myself. That's what I'd run.

Not so sure I believe that, maybe at cruising speed but not overall. You still have that car? This the same engine or one vs the other? For comparison's sake I'd want the same engine just EFI or carb.

It is the same engine no changes to the long block other than the intake system victor 5.0 to dual quads.
Self tuning set ups are a bit pricey and some FI setups dont seem to be as robust as factory stuff these days.

[Tiggie]

My tripminder always calcs an extra gallon on ten used. Last fill up was 16.5 gallons (pushing it!) and the trip said I used 18.1 of my 18 gallon tank...

[DerekTheGreat]

It is the same engine no changes to the long block other than the intake system victor 5.0 to dual quads.
Self tuning set ups are a bit pricey and some FI setups dont seem to be as robust as factory stuff these days.

Ok. Let me borrow it for about two weeks so I can see if it does better than my Town Car

[DerekTheGreat]

My tripminder always calcs an extra gallon on ten used. Last fill up was 16.5 gallons (pushing it!) and the trip said I used 18.1 of my 18 gallon tank...

I don't think Ashley's Mark VII is right either. But it also does that thing where it flashes "0 DTE" when we flip the key on or start it so I think that's what is confusing it.

[knucklehead0202]

Ha! My trip odometer doesn't even work so I just guess at mileage. Takes me a month to use a tank of gas anyway unless I take a little road trip. The day my other car got wrecked was the day i'd finally put the PI cluster in it. Trip odometer had 5 miles on it. Still haven't managed to get that cluster in the new car yet... My yardstick is when I drive to my pop's house and back, because it's roughly 100 miles each way.