2 wheel dr. maf,egr,stock coils,fuel filter, 1999 f150 w/4.6 226,000 ! autolite plugs! im new to forums and not on a computer much! this is really driving me crazy! the last thing that i can think of is the eet/or is it call ecm? all the help i can get thank you, codes were for MAF<EGR but still runs rough and i think im just missing something

 

just trying to figure out and new to forums

 

Autolite plugs? That may be a contributing issue, they have been known to have issues in the modulars. You replaced both coil packs? "Stock" as in Motorcraft? Have you ever replaced the plug wires? Did you use dielectric grease when you changed the plugs and coil packs? Whether you have a CEL or not, have you scanned it for codes? If you have codes, please post the exact numbers. Did you do a compression test when you changed the plugs? You replaced the EGR valve itself without testing it?

You need to test things rather than blindly throwing parts at it.

 

Oh NO, -Autolites are bad news and most likely your problem. They can't take the heat range for long before they turn colors and misfire like a biatch! Use ONLY -

MOTORCRAFT PLUGS
DENSO IRIDIUM'S
NGK IRDIUM'S

Iridium's can net you a litter better mileage and healthier miles before the it's time to service again.

Yea DON'T use Autolites or Bosch for the 97-03 V8's/ V10's. I've got a collection of nightmare picks on the subject lol.

 

egr was bad and the codes i got were p-171 p174 p1000 p102, these are after i changed everything , I know 171&174 are lean readings , I changed fuel filter, have right pressure on fuel rails. I found 5 vac lines behind battery that were cracked and fixed that and still runs but no power! Believe me i can't afford to throw money at this truck and all help i can get is just great, this truck is in very good shape but lot of miles 226000. thanks for the help

 

Have you cleared the codes to see if they come back? Can you answer the rest of my questions?

 

...

 

Heck with this guy, - he's not listening. Let him find out the hard way glc, if that's hows he's going to be. People like this are there own worse enemy IMO. Just about anyone would at-least answer question or ask "why", "what" if they don't understand, - This dude, yea, - Ignores his problems lol.

Shoot, I'd wiz on a spark-plug if id doer any good.

 

no not yet , but im doing it today then i'll hit u up and let u know. Man i really miss them 50's,60's,& 70's cars. anyway thanks i'll post later have 2 showings of my house today! and don t forget new to this computer stuff so ur buddy may think im not listening but let me tell you I AM thanks again

 

can only do what ob-2 says to do, and believe me that manuel has all different reasons! and i take it you been were im at before. thanks for ur imput

 

OBD2 doesn't tell you what to do, you have to research each code to understand what it's telling you. It's not cut and dried, all it's telling you is it has detected *something* is not right. You still have to go through a diagnosis.

Example are the P0171/P0174 lean codes. All this means is that it's getting too much air or not enough fuel. The system is able to correct for this up to a point - and when it gets past that point, it trips the code.

The P0102 MAF code means that the MAF circuit had lower than expected voltage (air flow). This can be an electrical issue or a bad MAF - but it can also mean that the engine is taking in air somewhere after the MAF.

Now - combine these and it's very possible that you have a major vacuum leak tripping all 3 codes. Everything works together when you have a computer managing the engine.

NOW - knowing what we know about these engines, the MOST common cause for excess air (vacuum leak) is a cracked/rotted PCV elbow at the back of the intake manifold.

 

GLC i have checked all vac's,pressureat rails , what i fold out yesterday was there is a electrical short in ign. somewere@ the truck has a intoxalok in it and is screwing it up! His gut i sold a 50 motor to put his big ole computer on it and thats what it reads and he tells me the guys putting the intoxaloc's IN are shorting wires out , and that the company that has these machines WON'T PAY TO FIX
Thanks for the help everything you have posted is what i did, I BELIEVE YOU KNOW YOUR STUFF THANKS AGAIN . will let you know what happens

 

well after all said and done blown head gasket LMAO

 

[QUOTE=torchred 05;4592259]Hey, me again. Got a 98 F150 4.6 with 201,000 miles. Started running rough recently and replaced spark plugs (Motorcraft), cleaned MAF, and checked compresssion. The truck idles very rough and shudders under acceleration. Truck feels terrible and has no power. Through it all, there is no check engine light. Isn't this very unusual? I would think if the truck is misfiring, there should be a code. Any ideas? Thanks[/QUOTE look at the injector caps on the intake side and see if they are missing or broken. I had the problem of a 5.4 running rough and loss of power and no codes. I changed coils and plugs and it stayed the same. Then i checked injectors and a cap was missing from the injector. I replaced them and now runs like new again. I hope this helps you.

 

check the rubber elbow at the back of the intake it might have a hole in it. The pcv tube the rubber elbows get holes in them and pull those codes.. i hope it helps you.