New distributor nightmare 89 F150

My truck goes thru several ignition modules a year, so we were advised to change the distributor. What a nightmare, instead of letting me take it to a shop my husband changed it. No power, so then after we worked for 3 days I finally take it to our local shop and now it misses so bad I barely got it home. They had the wiring on the cap, had it set for a carb not EFI still cant get it set right. My question is , on the old distributor my ignition module was positioned against the alternator on the right positioned left to right. They have the new one with the module positioned on the left side of the distributor facing front to back, should the new one be positioned the same as the old ?

Have you asked the shop any questions as to why it runs poorly . They should stand behind their work . At least let them try to solve this before doing anything yourself . If you or another shop does anything that lets them off the hook.


I wonder if they know enough to get it straightened out @VOLVO_V70. Replacing that module is an awfully basic job to not get it right on the first try.

@newbee41360_156861, while the distributor could be installed in a different position run and with no problem it seems that whoever did the work was unable to get it to run properly in any position. I have to wonder if the plug wires are in correct order.

Same. If hubby screwed the order up, and then the shop just kept them in that order…

A shop that would remove and reinstall a distributor and not confirm every aspect of the timing to be correct before closing the hood needs to re-think their choice of profession.

I wasn’t aware that the firing order for Carb was different than the one used for Efi… Hmmmm Could be but sounds like total BS to me.

As others have stated this is a fairly basic 101 type of issue. I’d be more inclined to find out why this vehicle goes thru modules as it does…that is not common. I suspect a ground issue and or wiring problem…

I’m the type where that sort of thing would bother me so I would simply solve the problemo…but I understand you are relying on a shop here…sometimes I forget that everyone isn’t a mechanic.

P.S. I also second what @Rod_Knox said…

A shop that would get a distributor job and send the vehicle out the door “missing so badly” that the owner “barely got it home” has already demonstrated that they shouldn’t be in the profession. :wink:

I have no idea what’s going on with this truck without vehicle in hand, but this is a TFI model ignition.

Repeated module failures can be caused by failure to clean the module mounting pad on the distributor and by not using the special grease that comes with the new module.
When setting the ignition timing the SPOUT connector MUST be disconnected before doing so.
Failure to do this will cause the timing to be off by as much as 10 degrees or more.

AFAIK, the firing order is different between the 302, 351, and 302 HO. Your truck should have one of the first 2 engines unless it’s been swapped out (unlikely) over the years with the HO.

I did and their response was they thought we had bad fuel, we dont

we rechecked the firing order when i got the truck home and they had the 3 & 5 reversed and the 7 & 4 reversed our firing order is 1, 3, 7, 2, 6, 5, 4, 8 for the EFI a carb firing is 1,5,4,2,6,3,7,8 they had the number 7 plug on the 4 and vise versa and the 3 on the 5 and vice versa. we have changed the module many times over the years. always cleaned the plate and put the grease that came with it. used quality and cheap modules , doesnt make a difference

research shows 2 the motor with a carb is 15426378 and EFI is 13726548

My service guide shows that all 5 liter engines were fuel injected that year, 1989, there were no carburetors. The firing order is 15426378

the connector was disconnected . i know it will do damage if it is connected while trying to time the vehicle, we turned the vehicle off and reconnected after we got it where we thought it was timed,then restarted the vehicle to let the computer take over, it idled great didnt miss but when we drove it it didnt have any power or speed when you gave it gas. we tried to adjust but couldnt get it right, so we took it to the shop and i barely made it home in it the truck missed so bad,so now we are trying to fix the problem, they had wires in wrong places, we changed them,put new wires and a few new plugs but now we cant get it to even sit and idle since the shop had it

yeah we just found the emissions label on the truck and it is the 154 rotation instead of the 137 will try and work on it again after labor day and see if we have better luck

well i found part pf our problem, our truck has a 154 rotation and not a 137. we found the emissions label on the truck that had the rotation label. gona try and work on it again after labor day, plus we are going to put an extra ground on. our auto parts dealer races cars and he has a buddy who had a truck that went thru the modules like ours and he put an extra ground wire and hasnt had to put a new one on since

On my older Ford truck w/302 (5L) the firing order is embossed right on the intake manifold. So if there’s any doubt, look there. Common sense of course says to mark the wires according to their positions at a time the truck is running correctly. One idea for the repeat ignition module failure problem, on some ignition system configurations there’s supposed to be a resistor in the line that powers the coil primary, which is switched out only during the cranking phase. If the ignition module expects that resistor to be there when the engine is running, and it isn’t, that could damage the ignition module over time by overheating.

I found the firing order on the emissions label this evening, will check next week on the resistor

I know that it may not seem like it at the moment, but keep in mind that the vast majority of problems that are perceived to be major often have a minor cause.

It’s very easy to overthink a problem and start at the end of the alphabet so to speak instead of the beginning.

Regarding the multiple ignition moduel failures I might ask if these modules were tested and actually found to be faulty or whether a guess was made at the module because of a no-spark situation?

And as for those modules, I learned early on when dealing with the Ford TFI ignition to always replace the module and pickup coil at the same time. Whatever causes one to fail causes the other to fail soon afterward. For the DIYer it’s easiest to just install a rebuilt distributor because replacing the pickup requires a special set of tools to deal with the drive gear.