97 5.3 Problems please help!

[97_5.3Expy]

Hello all,

I'd first off like to say hello. Name is Brian and i live in sunny Temecula California.

I recently purchased a 1997 Expedition that has the 5.3 v8 (xlt)

I am having some issues and would like to get some of your opinions on the matter.

I am getting codes P0305, P0174, P0171.

P0305- I have changed the spark plug with motor-craft and also changed the coil on plug, ran fuel injector cleaner through 2 full tanks of gas. After resetting the code I am still getting it, and can hear the misfire.

P0174, P0171- I did have a lose hose but I reconnected it and it seems to help a little, though both codes came back on. I have checked the PCV valve and it is good (no cracks or leaks) I cleaned the MAF as well.

Under acceleration I am also getting spark knock. I have started running 91 octane gas for the last couple of fill ups, but still getting it.

Any help would be very appreciated, I'm at a loss!

 

[FordandPolaris]

OK I am just starting with the simple stuff, you replaced the plug and coil on the driver side front cylinder? Just want to make sure you didn't have them reversed. Also not a big deal but you have a 5.4 haha. 5.3's are in late model Chevy pickups...

When you remove the PCV hose, can you feel it making vacuum at the valve cover end?

 

[toms89]

First... Fords mod motor is a 5.4 or 4.6.

Chevy has a 5.3.

P0305 is cylinder 5 misfire if google is correct.

That would be the first cylinder (closest to radiator) on the drivers side just to confirm you serviced the correct one.

P0174 and P0171 are bank 2 and bank 1 too lean.

http://www.expeditionforum.com/f27/rough-idle-p0171-p0174-heres-what-you-need-check-first-4926/

The spark knock you are getting is most likely a symptom of running too lean.

 

[toms89]

FordandPolaris beat me to it.. lol.

 

[bedrck46]

another item you may want to check/clean is the exhaust ports that go from the egr valve into the throttle body

 

[Yudaman]

FordandPolaris beat me to it.. lol.

He was fast and sneaky like a Ninja!

Everybody was Kung-Foo fighting....

 

[FordandPolaris]

Haha gotta be wily sometimes...

 

[97_5.3Expy]

Yup, realized I made the mistake. I used to have a Chevy Tahoe and after working so much on this expo my brains a little toasty. Guess ill have to let a mod know to change my name to 5.4 haha.

That is correct I changed the number 5 plug and coil that is on driver side closest to the radiator.

OK I am just starting with the simple stuff, you replaced the plug and coil on the driver side front cylinder? Just want to make sure you didn't have them reversed. Also not a big deal but you have a 5.4 haha. 5.3's are in late model Chevy pickups...

When you remove the PCV hose, can you feel it making vacuum at the valve cover end?

I will have to check later on today for that, the Vacuum should be coming from the end of the PCV valve correct?

another item you may want to check/clean is the exhaust ports that go from the egr valve into the throttle body

I've ran some cleaner through the throttle body, I'll check the ports as well.

 

[bedrck46]

it would be best to remove the throttle body to clean out the ports as you don't want anything going into the intake gaskets are cheap you just need the egr and throttle body gasket there is a very nice video on you tube that shows how bad they can get clogged

 

[97_5.3Expy]

I have checked the PCV Valve and there is no leaks or cracks in the hose or elbow. There is vacuum pressure coming from it so i believe it's ok.

it would be best to remove the throttle body to clean out the ports as you don't want anything going into the intake gaskets are cheap you just need the egr and throttle body gasket there is a very nice video on you tube that shows how bad they can get clogged

I will have to do that next, and hopefully that is the problem because I'm still lost at what could be causing the problem.

 

[97_5.3Expy]

Any other thoughts on the misfire?