7.3 no check engine light and it ran like crap, What I did to tune it up FOR THE NEWB
This is for my 7.3 IDI NEWBYS out there trying to make it work like a champ. These are the common problems I’ve had to overcome to make it run beautifully. I bought my 89 F250 cheap because the guy thought it was on its’ last leg. Shifted like poop on a stick, hard starts, lots of smoke, throttle response was junk, light were so dim you couldn’t see at night, ate oil .NO ENGINE LIGHT!This is a Run down list if you just got your IDI and are tuning the thing up. I didn't put a lot of things in detail, you can google it once you know the key words you're looking for.
The Engine:
Throttle:
If your Truck is older than 10 years old YOUR throttle cable is loose!!! No going around it. You need to know how to tighten it. There is NO adjustment screw for the throttle. Go underneath where the gas pedal is and put zips ties around the cable and use them as spacers to take up the slack… It will make your trucks throttle response like night and day.
Glowplugs:
Hearing clicking means YOU HAVE DEAD GLOWPLUGS OR A BAD GLOWPLUG WIRE. Aftermarket is junk they swell get stuck in block requires removal of heads to get out! Don’t try it. BUY Motorcraft or BERU! Which is who makes it for Motorcraft.
Glowplug relay(top only):
These things wear out if you’re getting a hard start and no clicking, turn on Truck, put a multi-meter on the plugs and make sure they are cycling full voltage at the plugs. If they are not. Replace! After market is junk again. The aftermarket ones I got it buzzed every time you turn on your engine, just don’t do it buy motorcraft
CDR:
If your engine smells,eats oil and your center air filter bolt covered in oil. Change or clean cdr valve, you will be glad you did it helps with a clean combustion and so your engine doesn’t eat oil. I cleaned mine with a plastic container filled with hot boiling water and simple green and shake it like a Polaroid picture till your satisfied and blow on the hole on the back to see if the diaphragm still takes pressure. Rinse with water afterwards of course and DRY IT OUT water is bad for diesels BAD BAD BAD so leave out in sun and let drain and dry out for a day. That's what I did but google CDR cleaning pick a method whatever you choose it needs cleaning.
Tach sensor:
Look for it check the wires, they WILL go bad. You won’t like limp mode for your transmission.
The injectors !
Simply if your injectors are clogged your truck will run like garbage. Clean them out, but how ? There are many ways to clean them out I personally like amsoil injector cleaner, stanadyne injector cleaner, and archoil 6200. All work great there are tons of opinions out there go ahead and pick.By the way Motorcraft cetane booster also helps a lot on startups DON”T overdo it, it will burn up your engine, it’s basically trying to make mediocre diesel into top grade stuff, not rocket fuel.
Check for leaks, if the injectors are wet, your o rings are rotten, if your fuel lines are hard then change them. Air gets into the lines of these and makes it harder to start in the morning. It makes your engine compartment smell like diesel , which will make your AC smell like diesel at idle in traffic, brain cells are good don’t kill them with diesel.
Fuel filters:
Ford OEM design sucks and is prone to leaking everywhere. Get a filter that has a built in drain valve, drain it for water during oil service. Also put a damn metal cap with a silicone seal ring on the Schrader valve that valve will eventually leak it’s a hard part to find so that makes it work for cheap.
Thermostats:
Get a Navistar or FORD, all others are set WRONG and will fail BAD and your truck will run like poor. Don’t do it, just buy the good one
If you are changing the thermostat and your valve cover is leaking NOW is the time to change it the valve cover on the passenger side requires you to take off the fuel filter bracket which is required for the thermostat housing. Two birds one stone.
Coolant:
SCA additives are essential. IF YOU RUN GREEN COLLANT NO SCA your engine will eat itself and die FAST. The cylinder walls are thin without SCA spots form around the cylinder walls and holes form. Your engine dies because it floods with coolant! ONCE THE BLOCK IS DEAD YOU NEED A NE ENGINE. Good times.... SO either get a good fleet long life maintenance free coolant made for diesels with SCA already added or buy ford SCA.
Flush your radiator Proper cooling is important for engine to not run like crap
Radiator caps matter! It maintains pressure so the boiling point is higher steam doesn’t cool. It’s cheap replace its one every couple years for kicks.
E4OD:
TPS/FIPL sensor:
This thing will jack up your shifting royally if you have an UNCALIBRATED TPS sensor. When uncalibrated it will run as if you have a bad transmission learn to adjust it and now that you have a tight throttle cable your WOD will be RIGHT on the money.
Transmission coolers are essential period. If you like replacing transmissions by all means don’t do it. Get a good one they are cheap and well worth it
Use extra filtration and make change it every 20-30k. The wix or mangefine work great it WILL SAVE YOUR TRANSMISSION if your trans isn’t already broken.
Change your fluid. GET A BIGGER PAN with a plug, just do it. It hard to flush your system out so to keep everything working great change your fluid often 30k is fine. Change it before it gets bad or close to bad, trans fluid is cheap trans rebuilds are not.
By the way your torque converter is crap for towing, "when" it breaks get a good one, change flex plate to.
Congrats your trans is now good to go!
Drive train:
I hear a thud when I stop, what is it? It’s the slip yoke, go to ford get the Teflon grease and grease the hell out of it. Be prepared to change the rear seal of the trans if it has never been changed..
The pumpkin in the back:
Just change the fluid it’s easy and well NO ONE EVER DOES, it’s not everlasting oil!!! Change it at least once while you own the truck.
Brakes:
You have an old ford you have one of two options: a vacuum leak or low vacuum. It just stuff most people don’t bother to really maintenance cause it's a pain to find. Check the vacuum pump for pressure and how fast it recovers, most of the time it just need a diaphragm, word to the wise you don’t have to go motorcraft, but you get what you pay for. So don’t go bargain basement they will just burn out and you won’t have brakes. Brakes are good they keep you from going HULK smash when a rice burner tries to cut you off! Don't be cheap.
If your brakes are crap make sure you have good vacuum pressure, if the brake light on the dash stays on a little longer than you think it should, it means you have a vacuum leak or vacuum pump that’s going out. Remember Good brakes Good vacuum. On the booster there is a one way valve they go bad and no one bothers to check them take it off and suck on it if you can suck and blow on it no problem it’s bad.
Chassis and suspension:
Check body mounts if your car rides hard and you already replaced shocks, check the mounts DO NOT GO POLY. They will rattle your head off. Also while your underneath check the radiator mounts if they are loose or bad. Bad ones will cause the radiator to crack can you say good bye to 350 dollars! Mounts are cheap replace them even if it’s poly.
Poly squeaks and will continue to squeak for all eternity, But they do ride better and perform better. My suggestion buy poly for the sway bar, end-links, and tie rod boots. It’s cheap. Use money saved and put extra sound proofing into cabin Sound batting on firewall and heat shielding etc. It will make road noise quieter, engine quieter, cabin cooler, music sounds better, let people outside deal with squeaking. You deal improved handling and comfortable cabin.
Radius arm bushing suck and so do rivets. Change them to grade 8 bolts and replace your bushings they are cheap and they make your drive much better. It an easy fix once you convert to nut and bolts.
Steering:
Your steering box is loose. As a ford owner it will always happen, there is an adjustment screw on the box adjust it, Adjust it in 1/8th turns increments , DO NOT go past ½ turns for the life of the truck if it goes past that time for a new box! Hopefully you've already checked tie rod ends, ball joints, center link and pitman arm for wear. Steering box is for the times when you've checked those and still it's loose.
Fuel Tanks:
The ¼ dread. If you own this ford truck long enough this will happen, the original design was a plastic boot, over time it snaps off and thus you run out of gas at the ¼ tank mark. Hutch and HARPOON look it up. You will be glad you did.
Alternator:
Mine ran fine but the output was 12.8 volts at idle. It would charge the batteries barely and as a result of this low voltage my headlights were non existent. It’s like thinking you have a 100watt bulb and getting 60watts of light. THAT’S NOT NORMAL buy a new one! Your night vision will thank you! 13.8 to 14v at idle FTW
Pretty much all of this never set off my engine light. In these IDI's they little more than glorified low oil pressure light warnings. So it's up to you to make it happen! Hope this helps someone out there, this forum helped me so much, I figured I should try to contribute.
This is for my 7.3 IDI NEWBYS out there trying to make it work like a champ. These are the common problems I’ve had to overcome to make it run beautifully. I bought my 89 F250 cheap because the guy thought it was on its’ last leg. Shifted like poop on a stick, hard starts, lots of smoke, throttle response was junk, light were so dim you couldn’t see at night, ate oil .NO ENGINE LIGHT!This is a Run down list if you just got your IDI and are tuning the thing up. I didn't put a lot of things in detail, you can google it once you know the key words you're looking for.
The Engine:
Throttle:
If your Truck is older than 10 years old YOUR throttle cable is loose!!! No going around it. You need to know how to tighten it. There is NO adjustment screw for the throttle. Go underneath where the gas pedal is and put zips ties around the cable and use them as spacers to take up the slack… It will make your trucks throttle response like night and day.
Glowplugs:
Hearing clicking means YOU HAVE DEAD GLOWPLUGS OR A BAD GLOWPLUG WIRE. Aftermarket is junk they swell get stuck in block requires removal of heads to get out! Don’t try it. BUY Motorcraft or BERU! Which is who makes it for Motorcraft.
Glowplug relay(top only):
These things wear out if you’re getting a hard start and no clicking, turn on Truck, put a multi-meter on the plugs and make sure they are cycling full voltage at the plugs. If they are not. Replace! After market is junk again. The aftermarket ones I got it buzzed every time you turn on your engine, just don’t do it buy motorcraft
CDR:
If your engine smells,eats oil and your center air filter bolt covered in oil. Change or clean cdr valve, you will be glad you did it helps with a clean combustion and so your engine doesn’t eat oil. I cleaned mine with a plastic container filled with hot boiling water and simple green and shake it like a Polaroid picture till your satisfied and blow on the hole on the back to see if the diaphragm still takes pressure. Rinse with water afterwards of course and DRY IT OUT water is bad for diesels BAD BAD BAD so leave out in sun and let drain and dry out for a day. That's what I did but google CDR cleaning pick a method whatever you choose it needs cleaning.
Tach sensor:
Look for it check the wires, they WILL go bad. You won’t like limp mode for your transmission.
The injectors !
Simply if your injectors are clogged your truck will run like garbage. Clean them out, but how ? There are many ways to clean them out I personally like amsoil injector cleaner, stanadyne injector cleaner, and archoil 6200. All work great there are tons of opinions out there go ahead and pick.By the way Motorcraft cetane booster also helps a lot on startups DON”T overdo it, it will burn up your engine, it’s basically trying to make mediocre diesel into top grade stuff, not rocket fuel.
Check for leaks, if the injectors are wet, your o rings are rotten, if your fuel lines are hard then change them. Air gets into the lines of these and makes it harder to start in the morning. It makes your engine compartment smell like diesel , which will make your AC smell like diesel at idle in traffic, brain cells are good don’t kill them with diesel.
Fuel filters:
Ford OEM design sucks and is prone to leaking everywhere. Get a filter that has a built in drain valve, drain it for water during oil service. Also put a damn metal cap with a silicone seal ring on the Schrader valve that valve will eventually leak it’s a hard part to find so that makes it work for cheap.
Thermostats:
Get a Navistar or FORD, all others are set WRONG and will fail BAD and your truck will run like poor. Don’t do it, just buy the good one
If you are changing the thermostat and your valve cover is leaking NOW is the time to change it the valve cover on the passenger side requires you to take off the fuel filter bracket which is required for the thermostat housing. Two birds one stone.
Coolant:
SCA additives are essential. IF YOU RUN GREEN COLLANT NO SCA your engine will eat itself and die FAST. The cylinder walls are thin without SCA spots form around the cylinder walls and holes form. Your engine dies because it floods with coolant! ONCE THE BLOCK IS DEAD YOU NEED A NE ENGINE. Good times.... SO either get a good fleet long life maintenance free coolant made for diesels with SCA already added or buy ford SCA.
Flush your radiator Proper cooling is important for engine to not run like crap
Radiator caps matter! It maintains pressure so the boiling point is higher steam doesn’t cool. It’s cheap replace its one every couple years for kicks.
E4OD:
TPS/FIPL sensor:
This thing will jack up your shifting royally if you have an UNCALIBRATED TPS sensor. When uncalibrated it will run as if you have a bad transmission learn to adjust it and now that you have a tight throttle cable your WOD will be RIGHT on the money.
Transmission coolers are essential period. If you like replacing transmissions by all means don’t do it. Get a good one they are cheap and well worth it
Use extra filtration and make change it every 20-30k. The wix or mangefine work great it WILL SAVE YOUR TRANSMISSION if your trans isn’t already broken.
Change your fluid. GET A BIGGER PAN with a plug, just do it. It hard to flush your system out so to keep everything working great change your fluid often 30k is fine. Change it before it gets bad or close to bad, trans fluid is cheap trans rebuilds are not.
By the way your torque converter is crap for towing, "when" it breaks get a good one, change flex plate to.
Congrats your trans is now good to go!
Drive train:
I hear a thud when I stop, what is it? It’s the slip yoke, go to ford get the Teflon grease and grease the hell out of it. Be prepared to change the rear seal of the trans if it has never been changed..
The pumpkin in the back:
Just change the fluid it’s easy and well NO ONE EVER DOES, it’s not everlasting oil!!! Change it at least once while you own the truck.
Brakes:
You have an old ford you have one of two options: a vacuum leak or low vacuum. It just stuff most people don’t bother to really maintenance cause it's a pain to find. Check the vacuum pump for pressure and how fast it recovers, most of the time it just need a diaphragm, word to the wise you don’t have to go motorcraft, but you get what you pay for. So don’t go bargain basement they will just burn out and you won’t have brakes. Brakes are good they keep you from going HULK smash when a rice burner tries to cut you off! Don't be cheap.
If your brakes are crap make sure you have good vacuum pressure, if the brake light on the dash stays on a little longer than you think it should, it means you have a vacuum leak or vacuum pump that’s going out. Remember Good brakes Good vacuum. On the booster there is a one way valve they go bad and no one bothers to check them take it off and suck on it if you can suck and blow on it no problem it’s bad.
Chassis and suspension:
Check body mounts if your car rides hard and you already replaced shocks, check the mounts DO NOT GO POLY. They will rattle your head off. Also while your underneath check the radiator mounts if they are loose or bad. Bad ones will cause the radiator to crack can you say good bye to 350 dollars! Mounts are cheap replace them even if it’s poly.
Poly squeaks and will continue to squeak for all eternity, But they do ride better and perform better. My suggestion buy poly for the sway bar, end-links, and tie rod boots. It’s cheap. Use money saved and put extra sound proofing into cabin Sound batting on firewall and heat shielding etc. It will make road noise quieter, engine quieter, cabin cooler, music sounds better, let people outside deal with squeaking. You deal improved handling and comfortable cabin.
Radius arm bushing suck and so do rivets. Change them to grade 8 bolts and replace your bushings they are cheap and they make your drive much better. It an easy fix once you convert to nut and bolts.
Steering:
Your steering box is loose. As a ford owner it will always happen, there is an adjustment screw on the box adjust it, Adjust it in 1/8th turns increments , DO NOT go past ½ turns for the life of the truck if it goes past that time for a new box! Hopefully you've already checked tie rod ends, ball joints, center link and pitman arm for wear. Steering box is for the times when you've checked those and still it's loose.
Fuel Tanks:
The ¼ dread. If you own this ford truck long enough this will happen, the original design was a plastic boot, over time it snaps off and thus you run out of gas at the ¼ tank mark. Hutch and HARPOON look it up. You will be glad you did.
Alternator:
Mine ran fine but the output was 12.8 volts at idle. It would charge the batteries barely and as a result of this low voltage my headlights were non existent. It’s like thinking you have a 100watt bulb and getting 60watts of light. THAT’S NOT NORMAL buy a new one! Your night vision will thank you! 13.8 to 14v at idle FTW
Pretty much all of this never set off my engine light. In these IDI's they little more than glorified low oil pressure light warnings. So it's up to you to make it happen! Hope this helps someone out there, this forum helped me so much, I figured I should try to contribute.
Last edited:
, wondering how the CE light, which has nothing to do with engine performance, was relevant.
