5.4L Triton timing set, replace oil pump?

[JExpedition07]

Mr.Sticker was right, a bit to early to declare a total victory yet. Now today I have a misfire that goes away when warm, it misses slightly for about a minute when cold then goes away. Nothing severe, but I can feel it and see it in the tach. Googling this issue doesn’t put my mind at ease..... Most diagnosis for this issue on past threads are low cylinder compression due to warn rings or warn valve seals that expand when warm.....oh boy. I have one old spark plug I left in the engine because it was ssssoooo torqued down it wouldn’t budge that I’ll change out tomorrow......I think a COP and injector can be ruled out since they’d still misfire when hot. Mechanic recommends a compression check on all cylinders. I’ll update what I find over the next few days.

 

[07navi]

Mr.Sticker was right, a bit to early to declare a total victory yet. Now today I have a misfire that goes away when warm, it misses slightly for about a minute when cold then goes away. Nothing severe, but I can feel it and see it in the tach. Googling this issue doesn’t put my mind at ease..... Most diagnosis for this issue on past threads are low cylinder compression due to warn rings or warn valve seals that expand when warm.....oh boy. I have one old spark plug I left in the engine because it was ssssoooo torqued down it wouldn’t budge that I’ll change out tomorrow......I think a COP and injector can be ruled out since they’d still misfire when hot. Mechanic recommends a compression check on all cylinders and it may be time to think about a reman or junk yard engine depending on findings. I’ll update what I find over the next few days.

Nah, probably that plug you didn't change.

 

[JExpedition07]

Nah, probably that plug you didn't change.

The misfire goes away if I rev the engine when cold. It is only at a cold idle. Does this give any better indications?

 

[07navi]

The misfire goes away if I rev the engine when cold. It is only at a cold idle. Does this give any better indications?

No, just change it and go from there...……..

 

[JExpedition07]

No, just change it and go from there...……..

Yeah I’m thinking it’ll be that plug, I soaked that one in carb cleaner and after that didn’t work WD and it still wouldn’t come out so I’m sure the oily residue left on it is the problem. I’m going to use my DeWalt impact to see if that’ll break it loose without plug breakage. It wasn’t feeling promising on the ratchet. No issue on the other 7, I guess the silver lining is it’s the easier cylinder to access.

 

[JExpedition07]

Mode 6 live (the limited data BlueDriver is showing) is still showing evap issues

 

[07navi]

Yeah I’m thinking it’ll be that plug, I soaked that one in carb cleaner and after that didn’t work WD and it still wouldn’t come out so I’m sure the oily residue left on it is the problem. I’m going to use my DeWalt impact to see if that’ll break it loose without plug breakage. It wasn’t feeling promising on the ratchet. No issue on the other 7, I guess the silver lining is it’s the easier cylinder to access.

No penetrants are going to do anything because you didn't crack it open a bit (it's sealed). You might as well impact it since it has to come out.

 

[07navi]

Mr.Sticker was right, a bit to early to declare a total victory yet. Now today I have a misfire that goes away when warm, it misses slightly for about a minute when cold then goes away. Nothing severe, but I can feel it and see it in the tach. Googling this issue doesn’t put my mind at ease..... Most diagnosis for this issue on past threads are low cylinder compression due to warn rings or warn valve seals that expand when warm.....oh boy. I have one old spark plug I left in the engine because it was ssssoooo torqued down it wouldn’t budge that I’ll change out tomorrow......I think a COP and injector can be ruled out since they’d still misfire when hot. Mechanic recommends a compression check on all cylinders. I’ll update what I find over the next few days.

It's not the compression because it would have to be so low to cause a misfire that you would be burning a gallon of oil every 6 months. Not valve stem seals or it would puff smoke every time you started it. Also the rings didn't suddenly wear out because it ran fine a month ago...……….none of that, you need to change that plug for starters.

 

[JExpedition07]

As far as I can tell *so far* the misfire appears to be gone with the new plug. I replaced the last old plug and replaced all 8 plug boots this morning. 2 of the old boots were warped pretty bad from when I bought the truck and there were loose plugs in the head allowing blow-by which partially melted them. The plug I took out looks like it was running slightly lean though so I may still have a vacuum issue or evap system throwing off the mixture.

 

[JExpedition07]

So far not a hiccup today, it’s the warmest we’ve been though this morning started out in the 50s and now it’s 70 degrees.