I got this 89 LX Convertible with the 5.0 motor.. wemt to change distrubutor cap but first checked to see how the plug wires went on google.. 137 blah blah was every 5.0 HO motor firing order.. i noticed it was different.. it has tje 154 non HO 302 firing order.. idk why... it looks just like a 5.0 foxbody motor.. has HO plates on intake.. everything is bone stone.. and it looks exactally like any foxbodys motor.. anyone know why that is??
Engine My Foxbody Firing order is different
- Thread starter AydenTv
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- Mar 7, 2002
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Most likely scenario is that someone swapped in a non-HO engine, likely from a Crown Vic, Grand Marquis, or Town car.
If you can get your hands on one of those bore scopes (I think that's what it's called pen camera maybe) look in a spark plug hole at the top of the piston, 'dish' in the center means low compression non HO, eye brows are higher compression HO pistons.
like it has ho intake and everything looks like a stock mustang motor besides the air filter.. not a mechanic, but if if ive had a problem i usua''y research and find out a fix , by pass, or why it is doing what it is doing.. but this one has me stumped on why the firing order is like it.. could it have a 302 from say a vic, t bird, or a f150.. and if so how would i tell fr... previous owner had it sitting in garage and i bought it for 1,400 and he by passed the heater core after test drive.. then after letting it run for like an hour looking it over i paid im got title etc.. went 2 miles and died.. crunk right up and died.. over and over all the way home lol found out it was spout connector it was missing but other thsn that it has had alot of vac lines hooked up wrong, the tv cable needs adjusting (hard shift into od and feels like ujoints are bad when letting off gas) and alot of stuff was just thrown together.. it also came with another computer (a9p) posi trac rear end, everything i could thow in trunk lol arm rests, headlights, another carpet, air filter, etc.. and was told some mexican sold it to him and the parts car a few years ago and heck its well worth 1,400 and even already sold quarter windows and ecu with wire harness and got back 400 dollars lol
- Mar 7, 2002
- 9,474
- 5,435
- 224
The "HO" intake bolts to all of the Windsor heads. In fact, the non-HO intake is visually identical other than the fact that the upper intake is flipped 180 degrees.
What actually dictates your firing order is the camshaft. Non-HO engines had a really mild camshaft that followed the same firing order as all of the other 289s and 302s. HO engines had a relatively aggressive camshaft for the time that followed the 351W firing order and eliminated the back-to-back firing of cylinders on the same bank for a smoother running engine, distinctive sound, and marginal increase in performance.
I honestly doubt someone went to all of the trouble of a cam swap to a lower-performance cam on an otherwise stock-appearing engine, so the more likely story is that it has probably had the engine replaced at some point, and that whether due to ignorance or economic reasons, they swapped in the engine from a non HO application.
Nothing jumps out at me as it being a swap car. Everything looks original 5.0 and right parts other than the power steering pump (should be black) and the ac compressor clutch. But, those could have been changed.
look at the corner of the heads. One side will have a random number. The other side will have a letter.
you want T.
S is bad
look at the corner of the heads. One side will have a random number. The other side will have a letter.
you want T.
S is bad
can you link a website or be more descriptive on where the corner if the heads are located and maybe why T is good and S is bad.. sorry i am a noob to mustangs and never really worked on one.. ive had a foxbody when i was younger but my grandpa did all the fixing for it.. now since im 30 and the internet is like it is i have been my own shady tree mechanic lol
Local guy bought a swapped vert' just like this. Engine was obviously out of something else because,they kept the intake setup on the drivers side
Anyway guy did a real good job with it,he bought some spare stuff I had laying around so he could make it right. Ac works and everything looks factory. But yeah, this one may not be and could very well had an engine replacement sometime in it's life.
it’s an identifier to the heads that are on the car. One clue as to the origin of the engine. There is a partial VIN, but it’s very difficult to see with the engine installed.
Anyway, corner of the head is a letter. T is the E7tE head that should be in the car. S is the E6SE head that comes in non-Ho 302s. An S an indicator the engine has a non-Ho long block.
a T is good, but the short block could still be the non-Ho variety. I see orange injectors, and I bet if you were to flip the intake manifold over to see the part number, it would be an e7 manifold and not the smaller E6 manifold.
you can see the head on the right has an R
that’s a 1985 E5AE head. One year only as far as I know
EDIT: corrected part numbers
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i have an 89 lx convertible wkth the 5.0 and aod transmission.. it would run right just needed a tune up bad.. now it will go down the road and start to surge bad and i cut it off and crank it back up then it runs perfect again then after 2 mins itll do the same thing till i cut it off and back on... any help would be greatly appreciated.. it also wont give me any codes and it has a hesitation... this car also has a non ho motor i believe (different fire order standard 5.0) ithe map sensor is unhooked and has a maf sensor... if i unplug maf sensor it will die
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Spiffy dog house you got there 
No codes from computer: take the computer out, I think it should be an A9L for an HO engine with a stick, you can open it up and look for burnt traces and/or leaking capacitors but honestly I would send it off and get it checked out by ecuexchange, you can find them on ebay.
I don't know how the non HO firing order with the HO computer effects the injector firing order though.
You should take that cone filter and replace it with a stock air box or get the tubing to get the filter into the fender well.
You mentioned a MAP sensor that is unhooked, I could not see but it should not have a vacuum line hooked to it, is that what you mean by unhooked or are the wires not plugged in.
No codes from computer: take the computer out, I think it should be an A9L for an HO engine with a stick, you can open it up and look for burnt traces and/or leaking capacitors but honestly I would send it off and get it checked out by ecuexchange, you can find them on ebay.
I don't know how the non HO firing order with the HO computer effects the injector firing order though.
You should take that cone filter and replace it with a stock air box or get the tubing to get the filter into the fender well.
You mentioned a MAP sensor that is unhooked, I could not see but it should not have a vacuum line hooked to it, is that what you mean by unhooked or are the wires not plugged in.
Pull the ECU out. See what it is. If it truely has the wrong firing order it wouldn’t run with a mistang ecu.
need to figure out the root cause of your issues
need to figure out the root cause of your issues
Ive tried different computers lol came with basically all the parts i could grab from an identical foxbody.. just didnt know what all i fr needed so i grabbed the basics lkke interior stuff the whole wire harness ecu (sold on ebay but swapped it out first to see) just didnt grab the main stuff like iac, tps sensor, salt and pepper shakers etc the main stuff ppl say goes bad with these.. but the map sensors vac lnes wasnt hooked to it and i do have the others factory air box amd maf sensor and have tried those... maybe the idle screw and tps was messed with too much?? everyone and their mother has played with it before i realized to do a quick google search and ask ppl who knows bout these lolSpiffy dog house you got there
No codes from computer: take the computer out, I think it should be an A9L for an HO engine with a stick, you can open it up and look for burnt traces and/or leaking capacitors but honestly I would send it off and get it checked out by ecuexchange, you can find them on ebay.
I don't know how the non HO firing order with the HO computer effects the injector firing order though.
You should take that cone filter and replace it with a stock air box or get the tubing to get the filter into the fender well.
You mentioned a MAP sensor that is unhooked, I could not see but it should not have a vacuum line hooked to it, is that what you mean by unhooked or are the wires not plugged in.
more reason to see what ECU is in it. They are wired differently