Engine missing

[Kody]

Did you just do a tune up because it was time, or was there a reason for doing it?

A gasoline engine cylinder needs 3 things to "fire"
Spark, at the right time
Fuel, in the right mix with air
Compression, above 130psi

Spark and fuel can be intermittent and you can chase your tail around a few times if you start there

Compression is pretty much black or white, good or bad, which is why its good to start there when there is a misfire, yes takes a bit of time but once its done you have a yes or no answer

New spark plug might help a lower compression cylinder fire more, so problem solved............but it isn't, because it wasn't the problem and it comes back.
Nothing wrong with getting new plugs wires and distributor parts, you do need these things eventually anyway, but finding the cause of misfire is better than hoping its fixed.

It could even be a bad alternator, they can cause misfire and tach jumping, but again you can swap out alternator and battery "hoping" to fix the problem but not really fix it, lol

But best to start with compression and then move on to spark and fuel

I got rid of my missing issue I had 2 clog injectors....but my tach is still bouncey and will just die at idle or while driving. Wont bump start after it dies when driving have to stop and start it with the key again. I've test fuel pressure it's good and doesn't fall off when it dies it acts like you shut the key off. I have replaced every sensor all the relays checked my fuses and all that. You said my alternator could cause a bouncey tach could one of the 2 fuseable links be bad?

 

[Kody]

I got rid of my missing issue I had 2 clog injectors....but my tach is still bouncey and will just die at idle or while driving. Wont bump start after it dies when driving have to stop and start it with the key again. I've test fuel pressure it's good and doesn't fall off when it dies it acts like you shut the key off. I have replaced every sensor all the relays checked my fuses and all that. You said my alternator could cause a bouncey tach could one of the 2 fuseable links be bad?

And also tested compression and my highest one was like 120ish pounds

 

[Kody]

Also, genuine question pertaining to your issue, when you remove the SPOUT connecter and check base timing, is the engine holding time steady, or shifting around a bunch?

Yes I made sure pull the spout thinset base timing...however I read somewhere that said its supposed to have the same voltage as your battery but when I did the test it was like half my battery voltage....and ideas as to why?

 

[RonD]

SPOUT will be 7volt average with engine running, there is no test voltage with key on engine off for SPOUT wire, could be any where from 0-12volts

Alternator can leak AC Voltage when it a diode is going bad, and that can effect tach, alternator won't work at all with either fusible link blown
Switch volt meter to AC volts
Start engine
Ground meter to alternator case
Touch other probe to B+ terminal on the back of the alternator(the one with the larger wire and nut)
.5vAC or under is OK, so less that 1/2 volt AC

Tach signal is from Coil "-" post, so if tach is acting up then TFI module is not grounding that terminal correctly, or coil is bad

And that would cause misfire for spark plugs as well
Ignition coil should have 12volts with key on, "+" termional, then it is Un-Grounded("-") to make a spark
So TFI pulses the ground on and off to make spark in time with RPMs of distributor, per hall effect sensor IN the distributor

Tach reflects how many times a minute the "-" terminal is Grounded

 

[Kody]

Ok I replaced my distributor with a brand new one but my old tfi was still good and I also just put in a brand new coil...is the ground wire on the tfi a different color other then black? And what would my reading look like on my voltmeter

 

[RonD]

TFI module images here: https://www.stangnet.com/mustang-forums/attachments/tfi_5-0_comparison-gif.250293/

There are two versions, grey and black, wiring is different so not interchangeable
You should have a Grey one on a 2.9l Ranger
Called "Push Start" version but nothing to do with bump or push starting vehicle, lol, it has a separate power path for START and RUN voltage.
And you should check those, RUN Power with key ON(12 volts), START Power with key turned to START(10volts), BOTH need to work

Coil NEGATIVE wire should pulse when distributor is turning
Unplug the coil's wiring connector hook volt meter or test light to Battery Positive
Hook other lead to Coil Negative wire
Crank engine, watch for pulses

If it pulses then TFI is OK
Now switch Positive wire to Coil "+" wire on connector, repeat test, if no pulse then coil is not getting 12v with key in START position, actually gets 10v

 

[Kody]

Ok where do I check the run and start voltage at? Cuz to me it's like you just shut the key off while your driving down the road

 

[PetroleumJunkie412]

Yes I made sure pull the spout thinset base timing...however I read somewhere that said its supposed to have the same voltage as your battery but when I did the test it was like half my battery voltage....and ideas as to why?

Double check.your base time. Ford TFI system can hold fractional degrees of timing. If its walking around on you with the spout connector pulled, it's your hall sensor.

 

[Kody]

TFI module images here: https://www.stangnet.com/mustang-forums/attachments/tfi_5-0_comparison-gif.250293/

There are two versions, grey and black, wiring is different so not interchangeable
You should have a Grey one on a 2.9l Ranger
Called "Push Start" version but nothing to do with bump or push starting vehicle, lol, it has a separate power path for START and RUN voltage.
And you should check those, RUN Power with key ON(12 volts), START Power with key turned to START(10volts), BOTH need to work

Coil NEGATIVE wire should pulse when distributor is turning
Unplug the coil's wiring connector hook volt meter or test light to Battery Positive
Hook other lead to Coil Negative wire
Crank engine, watch for pulses

If it pulses then TFI is OK
Now switch Positive wire to Coil "+" wire on connector, repeat test, if no pulse then coil is not getting 12v with key in START position, actually gets 10v

I looked at the images you sent me about the tfi and I believe my old distributor had a gray tfi and the new distributor I put in has a black one i do believe so would that make a difference in how it would run?

 

[Kody]

And if I dont have the recommended voltage what would I need to consider looking into to fix it?

I looked at the images you sent me about the tfi and I believe my old distributor had a gray tfi and the new distributor I put in has a black one i do believe so would that make a difference in how it would run?

 

[RonD]

You need the Grey one because thats what the vehicles wiring is for, they are not interchangeable

 

[Kody]

You need the Grey one because thats what the vehicles wiring is for, they are not interchangeable

Thank you so much for the help!! I pulled my distributor and swapped out the black tfi for one of the gray tfi's I had and problems are solved I greatly appreciate your help you've been way more knowledgeable and help then alot of things I've read or talked to people about. So thanks again very much

 

[RonD]

Good work

Thanks for posting the FIX

 

[PetroleumJunkie412]

Good work

Thanks for posting the FIX

So he found his engine?? ?

 

[Dirtman]

Its always in the last place you look.